1
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Pongrácz P, Dobos P. Behavioural differences and similarities between dog breeds: proposing an ecologically valid approach for canine behavioural research. Biol Rev Camb Philos Soc 2024. [PMID: 39101379 DOI: 10.1111/brv.13128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 07/19/2024] [Accepted: 07/26/2024] [Indexed: 08/06/2024]
Abstract
The behaviour of dogs holds great relevance for not only scientists from fundamental and applied research areas, but also due to the widespread roles of dogs in our societies as companions and working animals; their behaviour is also an important factor in animal and human welfare. A large proportion of dogs currently under human supervision belong to one of roughly 400 recognised breeds. Dog breeds can be characterised by distinctive, predictable and reproducible features, including some of their behavioural traits. To the scientist, the comparative analysis of the behaviour of dog breeds provides an opportunity for investigating an array of intriguing phenomena within an easily accessible model organism created from natural and human-driven evolutionary processes. There are many ways to design and conduct breed-related behavioural investigations, but such endeavours should always be based around biologically relevant research questions and lead to ecologically valid conclusions. In this review, we surveyed recent research efforts that included dog behaviour-related comparisons and applied a critical evaluation according to their methods of breed choice and the subsequent research design. Our aim was to assess whether these two fundamentally important components of experimental design provide a solid basis to reach valid conclusions. Based on 97 publications that fulfilled our selection criteria, we identified three primary methods used by researchers to select breeds for their investigations: (i) convenience sampling; (ii) hypothesis-driven, ancestry-based sampling; and (iii) hypothesis-driven, functional sampling. By using the SWOT (Strengths, Weaknesses, Opportunities, Threats) evaluation system, we highlight each of these techniques' merits and shortcomings. We identify when particular methods may be inherently unable to produce biologically meaningful results due to a mismatch between breed choice and the initial research goals. We hope that our evaluation will help researchers adopt best practices in experimental design regarding future dog breed comparisons.
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Affiliation(s)
- Péter Pongrácz
- Department of Ethology, ELTE Eötvös Loránd University, 1117 Pázmány Péter sétány 1/c, Budapest, Hungary
| | - Petra Dobos
- Department of Ethology, ELTE Eötvös Loránd University, 1117 Pázmány Péter sétány 1/c, Budapest, Hungary
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2
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Al Aiyan A, Balan R, Ghebrehiwot E, Mihreteab Y, Zerom S, Gebreigziabiher S, AlDarwich A, Willingham AL, Kishore U. Mapping of the exterior architecture of the mesocephalic canine brain. Sci Rep 2024; 14:17147. [PMID: 39060275 PMCID: PMC11282252 DOI: 10.1038/s41598-024-67343-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
Despite extensive studies published on the canine brain, inconsistencies and disagreements in the nomenclature and representation of various cerebral structures continue to exist. This study aimed to create a comprehensive mapping of the external architecture of the mesocephalic canine brain with a focus on the major gyri and sulci. Standardized dissection techniques were used on 20 ethically sourced brains obtained from 6 to 10-year-old dogs that were free of neurological disorders. Distinct gyri and sulci with unique locations and bordering structures were observed. Thus, it was possible to identify the often-ignored subprorean gyrus. In addition, this study was able to illustrate the unique locations and bordering structures of gyri and sulci. The findings can contribute to a consensus among researchers on the canine brain anatomy and assist in clarifying the inconsistencies in cerebral structure representation. Furthermore, the results of this study may hold significant implications for veterinary medicine and neuroscience and serve as a foundation for the development of diagnostic and therapeutic approaches for various neurological diseases in dogs. Our findings offer valuable insights into the unique evolutionary adaptations and specialized behaviors of the canine brain, thereby increasing awareness about the neural structures that enable dogs to demonstrate their unique traits.
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Affiliation(s)
- Ahmad Al Aiyan
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates.
| | - Rinsha Balan
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Even Ghebrehiwot
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Yotam Mihreteab
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Simona Zerom
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Senit Gebreigziabiher
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Adnan AlDarwich
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Arve Lee Willingham
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Uday Kishore
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al Ain, United Arab Emirates
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3
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Foss KD, Billhymer AC. Magnetic resonance imaging in canine idiopathic epilepsy: a mini-review. Front Vet Sci 2024; 11:1427403. [PMID: 39021411 PMCID: PMC11251927 DOI: 10.3389/fvets.2024.1427403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Accepted: 06/19/2024] [Indexed: 07/20/2024] Open
Abstract
Magnetic resonance imaging (MRI) in an integral part of the diagnostic workup in canines with idiopathic epilepsy (IE). While highly sensitive and specific in identifying structural lesions, conventional MRI is unable to detect changes at the microscopic level. Utilizing more advanced neuroimaging techniques may provide further information on changes at the neuronal level in the brain of canines with IE, thus providing crucial information on the pathogenesis of canine epilepsy. Additionally, earlier detection of these changes may aid clinicians in the development of improved and targeted therapies. Advances in MRI techniques are being developed which can assess metabolic, cellular, architectural, and functional alterations; as well alterations in neuronal tissue mechanical properties, some of which are currently being applied in research on canine IE. This mini-review focuses on novel MRI techniques being utilized to better understand canine epilepsy, which include magnetic resonance spectroscopy, diffusion-weighted imaging, diffusion tensor imaging, perfusion-weighted imaging, voxel based morphometry, and functional MRI; as well as techniques applied in human medicine and their potential use in veterinary species.
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Affiliation(s)
- Kari D. Foss
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, United States
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4
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Vogel JW, Alexander-Bloch AF, Wagstyl K, Bertolero MA, Markello RD, Pines A, Sydnor VJ, Diaz-Papkovich A, Hansen JY, Evans AC, Bernhardt B, Misic B, Satterthwaite TD, Seidlitz J. Deciphering the functional specialization of whole-brain spatiomolecular gradients in the adult brain. Proc Natl Acad Sci U S A 2024; 121:e2219137121. [PMID: 38861593 PMCID: PMC11194492 DOI: 10.1073/pnas.2219137121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/27/2024] [Indexed: 06/13/2024] Open
Abstract
Cortical arealization arises during neurodevelopment from the confluence of molecular gradients representing patterned expression of morphogens and transcription factors. However, whether similar gradients are maintained in the adult brain remains unknown. Here, we uncover three axes of topographic variation in gene expression in the adult human brain that specifically capture previously identified rostral-caudal, dorsal-ventral, and medial-lateral axes of early developmental patterning. The interaction of these spatiomolecular gradients i) accurately reconstructs the position of brain tissue samples, ii) delineates known functional territories, and iii) can model the topographical variation of diverse cortical features. The spatiomolecular gradients are distinct from canonical cortical axes differentiating the primary sensory cortex from the association cortex, but radiate in parallel with the axes traversed by local field potentials along the cortex. We replicate all three molecular gradients in three independent human datasets as well as two nonhuman primate datasets and find that each gradient shows a distinct developmental trajectory across the lifespan. The gradients are composed of several well-known transcription factors (e.g., PAX6 and SIX3), and a small set of genes shared across gradients are strongly enriched for multiple diseases. Together, these results provide insight into the developmental sculpting of functionally distinct brain regions, governed by three robust transcriptomic axes embedded within brain parenchyma.
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Affiliation(s)
- Jacob W. Vogel
- Department of Clinical Sciences Malmö, SciLifeLab, Lund University, Lund, Sweden202 13
- Lifespan Informatics and Neuroimaging Center, University of Pennsylvania, Philadelphia, PA19104
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
| | - Aaron F. Alexander-Bloch
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
- Department of Child and Adolescent Psychiatry and Behavioral Science, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
- Penn-Children’s Hospital of Philadelphia Lifespan Brain Institute, University of Pennsylvania, Philadelphia, PA19104
| | - Konrad Wagstyl
- Wellcome Centre for Human Neuroimaging, Institute of Neurology, University College London, LondonWC1N 3AR, United Kingdom
| | - Maxwell A. Bertolero
- Lifespan Informatics and Neuroimaging Center, University of Pennsylvania, Philadelphia, PA19104
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
| | - Ross D. Markello
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QCH3A 2B4, Canada
| | - Adam Pines
- Lifespan Informatics and Neuroimaging Center, University of Pennsylvania, Philadelphia, PA19104
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA94305
| | - Valerie J. Sydnor
- Lifespan Informatics and Neuroimaging Center, University of Pennsylvania, Philadelphia, PA19104
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
| | - Alex Diaz-Papkovich
- Quantitative Life Sciences, McGill University, Montreal, QCH3A 1E3, Canada
- McGill Genome Centre, McGill University, Montreal, QCH3A 0G1, Canada
| | - Justine Y. Hansen
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QCH3A 2B4, Canada
| | - Alan C. Evans
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QCH3A 2B4, Canada
| | - Boris Bernhardt
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QCH3A 2B4, Canada
| | - Bratislav Misic
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QCH3A 2B4, Canada
| | - Theodore D. Satterthwaite
- Lifespan Informatics and Neuroimaging Center, University of Pennsylvania, Philadelphia, PA19104
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
- Penn-Children’s Hospital of Philadelphia Lifespan Brain Institute, University of Pennsylvania, Philadelphia, PA19104
| | - Jakob Seidlitz
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA19104
- Department of Child and Adolescent Psychiatry and Behavioral Science, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
- Penn-Children’s Hospital of Philadelphia Lifespan Brain Institute, University of Pennsylvania, Philadelphia, PA19104
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5
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Foster M, Dwibhashyam S, Patel D, Gupta K, Matz OC, Billings BK, Bitterman K, Bertelson M, Tang CY, Mars RB, Raghanti MA, Hof PR, Sherwood CC, Manger PR, Spocter MA. Comparative anatomy of the caudate nucleus in canids and felids: Associations with brain size, curvature, cross-sectional properties, and behavioral ecology. J Comp Neurol 2024; 532:e25618. [PMID: 38686628 DOI: 10.1002/cne.25618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 03/30/2024] [Accepted: 04/16/2024] [Indexed: 05/02/2024]
Abstract
The evolutionary history of canids and felids is marked by a deep time separation that has uniquely shaped their behavior and phenotype toward refined predatory abilities. The caudate nucleus is a subcortical brain structure associated with both motor control and cognitive, emotional, and executive functions. We used a combination of three-dimensional imaging, allometric scaling, and structural analyses to compare the size and shape characteristics of the caudate nucleus. The sample consisted of MRI scan data obtained from six canid species (Canis lupus lupus, Canis latrans, Chrysocyon brachyurus, Lycaon pictus, Vulpes vulpes, Vulpes zerda), two canid subspecies (Canis lupus familiaris, Canis lupus dingo), as well as three felids (Panthera tigris, Panthera uncia, Felis silvestris catus). Results revealed marked conservation in the scaling and shape attributes of the caudate nucleus across species, with only slight deviations. We hypothesize that observed differences in caudate nucleus size and structure for the domestic canids are reflective of enhanced cognitive and emotional pathways that possibly emerged during domestication.
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Affiliation(s)
- Michael Foster
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
| | - Sai Dwibhashyam
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
| | - Devan Patel
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
| | - Kanika Gupta
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
| | - Olivia C Matz
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
| | - Brendon K Billings
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Kathleen Bitterman
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
| | - Mads Bertelson
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Frederiksberg, Denmark
| | - Cheuk Y Tang
- Departments of Radiology and Psychiatry, BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Rogier B Mars
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
- Donders Institute for Brain, Cognition and Behavior, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Mary Ann Raghanti
- Department of Anthropology and School of Biomedical Sciences, Kent State University, Kent, Ohio, USA
| | - Patrick R Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- New York Consortium in Evolutionary Primatology, New York, New York, USA
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, District of Columbia, USA
| | - Paul R Manger
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Muhammad A Spocter
- Department of Anatomy, Des Moines University, West Des Moines, Iowa, USA
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
- College of Veterinary Medicine, Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
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6
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Donohue LK, Buesing M, Peterson KD, Ersoz C, Russell LJ, Mowat FM. Screen interaction behavior in companion dogs: results from a dog owner survey. Appl Anim Behav Sci 2024; 270:106151. [PMID: 38223845 PMCID: PMC10783809 DOI: 10.1016/j.applanim.2023.106151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2024]
Abstract
Despite availability of video content marketed for dog (Canis familiaris) entertainment, there is little information on dog behaviors when viewing content, nor describing which content is engaging. The aims of this study were to define demographics of dogs that engage with screens, owner observed behaviors, and perceived content interest. A digital survey was distributed to dog owners (03/2022-03/2023). We collected demographics, home environment, owner-rated behaviors, content interest, and interest in 4 presented videos. We compared the representation of dogs from different purebred dog groups (categorized by job/purpose by the American Kennel Club) with the estimated general purebred dog population. Most respondents (total n=1,246) lived in the USA (89%). Median age was 4 years, 54% were purebred, 51% were female. Most (86%, n=1,077) stated their dog watched screen content. Excitement behaviors were often described: 78% of dogs approached the screen, 76% vocalized. Many owners played videos for their dogs when left alone. Dogs most frequently engaged with animal content; dogs were the most popular animal. Age and visual status influenced the frequency of perceived interaction; age and breed influenced content interest. Within purebred dogs that were stated to watch content, there was a relative over-representation of "sporting" and "herding"-type breeds. A dog's age, visual status, and breed type may influence their interest in video content at home. Because many owners reported excitement in their dogs in reaction to screen content, owners may wish to determine whether video content would be suitable for use when their dogs are left alone.
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Affiliation(s)
- LK Donohue
- University of Wisconsin-Madison School of Veterinary Medicine, Department of Surgical Sciences, Madison, WI, USA
| | - M Buesing
- University of Wisconsin-Madison School of Veterinary Medicine, Department of Surgical Sciences, Madison, WI, USA
| | - KD Peterson
- University of Wisconsin-Madison School of Medicine and Public Health, Department of Ophthalmology and Visual Sciences, Madison, WI, USA
| | - C Ersoz
- University of Wisconsin-Madison School of Veterinary Medicine, Department of Surgical Sciences, Madison, WI, USA
| | - LJ Russell
- University of Wisconsin-Madison School of Veterinary Medicine, Department of Surgical Sciences, Madison, WI, USA
| | - FM Mowat
- University of Wisconsin-Madison School of Veterinary Medicine, Department of Surgical Sciences, Madison, WI, USA
- University of Wisconsin-Madison School of Medicine and Public Health, Department of Ophthalmology and Visual Sciences, Madison, WI, USA
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7
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Leonetti S, Cimarelli G, Hersh TA, Ravignani A. Why do dogs wag their tails? Biol Lett 2024; 20:20230407. [PMID: 38229554 PMCID: PMC10792393 DOI: 10.1098/rsbl.2023.0407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/11/2023] [Indexed: 01/18/2024] Open
Abstract
Tail wagging is a conspicuous behaviour in domestic dogs (Canis familiaris). Despite how much meaning humans attribute to this display, its quantitative description and evolutionary history are rarely studied. We summarize what is known about the mechanism, ontogeny, function and evolution of this behaviour. We suggest two hypotheses to explain its increased occurrence and frequency in dogs compared to other canids. During the domestication process, enhanced rhythmic tail wagging behaviour could have (i) arisen as a by-product of selection for other traits, such as docility and tameness, or (ii) been directly selected by humans, due to our proclivity for rhythmic stimuli. We invite testing of these hypotheses through neurobiological and ethological experiments, which will shed light on one of the most readily observed yet understudied animal behaviours. Targeted tail wagging research can be a window into both canine ethology and the evolutionary history of characteristic human traits, such as our ability to perceive and produce rhythmic behaviours.
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Affiliation(s)
- Silvia Leonetti
- Comparative Bioacoustics Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- Department of Life Sciences and Systems Biology, University of Turin, Turin, Italy
- Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy
| | - Giulia Cimarelli
- Domestication Lab, Konrad Lorenz Institute of Ethology, Department of Interdisciplinary Life Sciences, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Taylor A. Hersh
- Comparative Bioacoustics Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- Marine Mammal Institute, Oregon State University, Newport, OR, USA
| | - Andrea Ravignani
- Comparative Bioacoustics Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
- Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy
- Center for Music in the Brain, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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8
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Ferreira VHB, Lansade L, Calandreau L, Cunha F, Jensen P. Are domesticated animals dumber than their wild relatives? A comprehensive review on the domestication effects on animal cognitive performance. Neurosci Biobehav Rev 2023; 154:105407. [PMID: 37769929 DOI: 10.1016/j.neubiorev.2023.105407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 09/21/2023] [Accepted: 09/22/2023] [Indexed: 10/03/2023]
Abstract
Animal domestication leads to diverse behavioral, physiological, and neurocognitive changes in domesticated species compared to their wild relatives. However, the widely held belief that domesticated species are inherently less "intelligent" (i.e., have lower cognitive performance) than their wild counterparts requires further investigation. To investigate potential cognitive disparities, we undertook a thorough review of 88 studies comparing the cognitive performance of domesticated and wild animals. Approximately 30% of these studies showed superior cognitive abilities in wild animals, while another 30% highlighted superior cognitive abilities in domesticated animals. The remaining 40% of studies found similar cognitive performance between the two groups. Therefore, the question regarding the presumed intelligence of wild animals and the diminished cognitive ability of domesticated animals remains unresolved. We discuss important factors/limitations for interpreting past and future research, including environmental influences, diverse objectives of domestication (such as breed development), developmental windows, and methodological issues impacting cognitive comparisons. Rather than perceiving these limitations as constraints, future researchers should embrace them as opportunities to expand our understanding of the complex relationship between domestication and animal cognition.
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Affiliation(s)
- Vitor Hugo Bessa Ferreira
- IFM Biology, AVIAN Behavioural Genomics and Physiology group, Linköping University, 581 83 Linköping, Sweden; INRAE, CNRS, IFCE, Université de Tours, Centre Val de Loire UMR Physiologie de la Reproduction et des Comportements, 37380 Nouzilly, France.
| | - Léa Lansade
- INRAE, CNRS, IFCE, Université de Tours, Centre Val de Loire UMR Physiologie de la Reproduction et des Comportements, 37380 Nouzilly, France
| | - Ludovic Calandreau
- INRAE, CNRS, IFCE, Université de Tours, Centre Val de Loire UMR Physiologie de la Reproduction et des Comportements, 37380 Nouzilly, France
| | - Felipe Cunha
- IFM Biology, AVIAN Behavioural Genomics and Physiology group, Linköping University, 581 83 Linköping, Sweden
| | - Per Jensen
- IFM Biology, AVIAN Behavioural Genomics and Physiology group, Linköping University, 581 83 Linköping, Sweden.
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9
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Barton SA, Kent M, Hecht EE. Neuroanatomical asymmetry in the canine brain. Brain Struct Funct 2023; 228:1657-1669. [PMID: 37436502 DOI: 10.1007/s00429-023-02677-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 07/01/2023] [Indexed: 07/13/2023]
Abstract
The brains of humans and non-human primates exhibit left/right asymmetries in grey matter morphology, white matter connections, and functional responses. These asymmetries have been implicated in specialized behavioral adaptations such as language, tool use, and handedness. Left/right asymmetries are also observed in behavioral tendencies across the animal kingdom, suggesting a deep evolutionary origin for the neural mechanisms underlying lateralized behavior. However, it is still unclear to what extent brain asymmetries supporting lateralized behaviors are present in other large-brained animals outside the primate order. Canids and other carnivorans evolved large, complex brains independently and convergently with primates, and exhibit lateralized behaviors. Therefore, domestic dogs offer an opportunity to address this question. We examined T2-weighted MRI images of 62 dogs from 33 breeds, opportunistically collected from a veterinary MRI scanner from dogs who were referred for neurological examination but were not found to show any neuropathology. Volumetrically asymmetric regions of gray matter included portions of the temporal and frontal cortex, in addition to portions of the cerebellum, brainstem, and other subcortical regions. These results are consistent with the perspective that asymmetry may be a common feature underlying the evolution of complex brains and behavior across clades, and provide neuro-organizational information that is likely relevant to the growing field of canine behavioral neuroscience.
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Affiliation(s)
- Sophie A Barton
- Department of Human Evolutionary Biology, Harvard University, Cambridge, 02138, USA.
| | - Marc Kent
- College of Veterinary Medicine, University of Georgia, Athens, 30602, USA
| | - Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, Cambridge, 02138, USA
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10
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Gergely A, Gábor A, Gácsi M, Kis A, Czeibert K, Topál J, Andics A. Dog brains are sensitive to infant- and dog-directed prosody. Commun Biol 2023; 6:859. [PMID: 37596318 PMCID: PMC10439206 DOI: 10.1038/s42003-023-05217-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 08/04/2023] [Indexed: 08/20/2023] Open
Abstract
When addressing preverbal infants and family dogs, people tend to use specific speech styles. While recent studies suggest acoustic parallels between infant- and dog-directed speech, it is unclear whether dogs, like infants, show enhanced neural sensitivity to prosodic aspects of speech directed to them. Using functional magnetic resonance imaging on awake unrestrained dogs we identify two non-primary auditory regions, one that involve the ventralmost part of the left caudal Sylvian gyrus and the temporal pole and the other at the transition of the left caudal and rostral Sylvian gyrus, which respond more to naturalistic dog- and/or infant-directed speech than to adult-directed speech, especially when speak by female speakers. This activity increase is driven by sensitivity to fundamental frequency mean and variance resulting in positive modulatory effects of these acoustic parameters in both aforementioned non-primary auditory regions. These findings show that the dog auditory cortex, similarly to that of human infants, is sensitive to the acoustic properties of speech directed to non-speaking partners. This increased neuronal responsiveness to exaggerated prosody may be one reason why dogs outperform other animals when processing speech.
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Affiliation(s)
- Anna Gergely
- Institute of Cognitive Neuroscience and Psychology, ELTE-ELKH NAP Comparative Ethology research group, Research Centre for Natural Sciences, Budapest, Hungary.
| | - Anna Gábor
- Department of Ethology, Eötvös Loránd University, Budapest, Hungary
- Neuroethology of Communication Lab, Department of Ethology, Eötvös Loránd University, Budapest, Hungary
| | - Márta Gácsi
- Department of Ethology, Eötvös Loránd University, Budapest, Hungary
- ELKH-ELTE Comparative Ethology Research Group, Budapest, Hungary
| | - Anna Kis
- Institute of Cognitive Neuroscience and Psychology, ELTE-ELKH NAP Comparative Ethology research group, Research Centre for Natural Sciences, Budapest, Hungary
| | - Kálmán Czeibert
- Department of Ethology, Eötvös Loránd University, Budapest, Hungary
| | - József Topál
- Institute of Cognitive Neuroscience and Psychology, ELTE-ELKH NAP Comparative Ethology research group, Research Centre for Natural Sciences, Budapest, Hungary
| | - Attila Andics
- Department of Ethology, Eötvös Loránd University, Budapest, Hungary
- Neuroethology of Communication Lab, Department of Ethology, Eötvös Loránd University, Budapest, Hungary
- ELTE NAP Canine Brain Research Group, Budapest, Hungary
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11
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Morrill K, Chen F, Karlsson E. Comparative neurogenetics of dog behavior complements efforts towards human neuropsychiatric genetics. Hum Genet 2023; 142:1231-1246. [PMID: 37578529 DOI: 10.1007/s00439-023-02580-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/02/2023] [Indexed: 08/15/2023]
Abstract
Domestic dogs display a wide array of heritable behaviors that have intermediate genetic complexity thanks to a long history of human-influenced selection. Comparative genetics in dogs could address the scarcity of non-human neurogenetic systems relevant to human neuropsychiatric disorders, which are characterized by mental, emotional, and behavioral symptoms and involve vastly complex genetic and non-genetic risk factors. Our review describes the diverse behavioral "phenome" of domestic dogs, past and ongoing sources of behavioral selection, and the state of canine behavioral genetics. We highlight two naturally disordered behavioral domains that illustrate how dogs may prove useful as a comparative, forward neurogenetic system: canine age-related cognitive dysfunction, which can be examined more rapidly given the attenuated lifespan of dogs, and compulsive disorders, which may have genetic roots in purpose-bred behaviors. Growing community science initiatives aimed at the companion dog population will be well suited to investigating such complex behavioral phenotypes and offer a comparative resource that parallels human genomic initiatives in scale and dimensionality.
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Affiliation(s)
- Kathleen Morrill
- Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
- Vertebrate Genome Biology, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Morningside Graduate School of Biomedical Sciences UMass Chan Medical School, Worcester, MA, USA.
| | - Frances Chen
- Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Vertebrate Genome Biology, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Elinor Karlsson
- Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Vertebrate Genome Biology, Broad Institute of MIT and Harvard, Cambridge, MA, USA
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12
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Sexton CL, Buckley C, Lieberfarb J, Subiaul F, Hecht EE, Bradley BJ. What Is Written on a Dog's Face? Evaluating the Impact of Facial Phenotypes on Communication between Humans and Canines. Animals (Basel) 2023; 13:2385. [PMID: 37508162 PMCID: PMC10376741 DOI: 10.3390/ani13142385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 07/15/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
Facial phenotypes are significant in communication with conspecifics among social primates. Less is understood about the impact of such markers in heterospecific encounters. Through behavioral and physical phenotype analyses of domesticated dogs living in human households, this study aims to evaluate the potential impact of superficial facial markings on dogs' production of human-directed facial expressions. That is, this study explores how facial markings, such as eyebrows, patches, and widow's peaks, are related to expressivity toward humans. We used the Dog Facial Action Coding System (DogFACS) as an objective measure of expressivity, and we developed an original schematic for a standardized coding of facial patterns and coloration on a sample of more than 100 male and female dogs (N = 103), aged from 6 months to 12 years, representing eight breed groups. The present study found a statistically significant, though weak, correlation between expression rate and facial complexity, with dogs with plainer faces tending to be more expressive (r = -0.326, p ≤ 0.001). Interestingly, for adult dogs, human companions characterized dogs' rates of facial expressivity with more accuracy for dogs with plainer faces. Especially relevant to interspecies communication and cooperation, within-subject analyses revealed that dogs' muscle movements were distributed more evenly across their facial regions in a highly social test condition compared to conditions in which they received ambiguous cues from their owners. On the whole, this study provides an original evaluation of how facial features may impact communication in human-dog interactions.
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Affiliation(s)
- Courtney L Sexton
- Department of Population Health Sciences, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, DC 20052, USA
| | - Colleen Buckley
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, DC 20052, USA
| | | | - Francys Subiaul
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, DC 20052, USA
- Department of Speech, Language and Hearing Sciences, The George Washington University, Washington, DC 20052, USA
| | - Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Brenda J Bradley
- Center for the Advanced Study of Human Paleobiology, Department of Anthropology, The George Washington University, Washington, DC 20052, USA
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13
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Boch M, Wagner IC, Karl S, Huber L, Lamm C. Functionally analogous body- and animacy-responsive areas are present in the dog (Canis familiaris) and human occipito-temporal lobe. Commun Biol 2023; 6:645. [PMID: 37369804 PMCID: PMC10300132 DOI: 10.1038/s42003-023-05014-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Comparing the neural correlates of socio-cognitive skills across species provides insights into the evolution of the social brain and has revealed face- and body-sensitive regions in the primate temporal lobe. Although from a different lineage, dogs share convergent visuo-cognitive skills with humans and a temporal lobe which evolved independently in carnivorans. We investigated the neural correlates of face and body perception in dogs (N = 15) and humans (N = 40) using functional MRI. Combining univariate and multivariate analysis approaches, we found functionally analogous occipito-temporal regions involved in the perception of animate entities and bodies in both species and face-sensitive regions in humans. Though unpredicted, we also observed neural representations of faces compared to inanimate objects, and dog compared to human bodies in dog olfactory regions. These findings shed light on the evolutionary foundations of human and dog social cognition and the predominant role of the temporal lobe.
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Affiliation(s)
- Magdalena Boch
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, Vienna, Austria.
- Department of Cognitive Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria.
| | - Isabella C Wagner
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, Vienna, Austria
- Vienna Cognitive Science Hub, University of Vienna, Vienna, Austria
- Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Sabrina Karl
- Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, Vienna, Austria
| | - Ludwig Huber
- Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, Vienna, Austria
| | - Claus Lamm
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, Vienna, Austria
- Vienna Cognitive Science Hub, University of Vienna, Vienna, Austria
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14
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Rogers Flattery CN, Abdulla M, Barton SA, Michlich JM, Trut LN, Kukekova AV, Hecht EE. The brain of the silver fox (Vulpes vulpes): a neuroanatomical reference of cell-stained histological and MRI images. Brain Struct Funct 2023; 228:1177-1189. [PMID: 37160458 PMCID: PMC11192273 DOI: 10.1007/s00429-023-02648-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 04/21/2023] [Indexed: 05/11/2023]
Abstract
Although the silver fox (Vulpes vulpes) has been largely overlooked by neuroscientists, it has the potential to serve as a powerful model for the investigation of brain-behavior relationships. The silver fox is a melanistic variant of the red fox. Within this species, the long-running Russian farm-fox experiment has resulted in different strains bred to show divergent behavior. Strains bred for tameness, aggression, or without selection on behavior present an excellent opportunity to investigate neuroanatomical changes underlying behavioral characteristics. Here, we present a histological and MRI neuroanatomical reference of a fox from the conventional strain, which is bred without behavioral selection. This can provide an anatomical basis for future studies of the brains of foxes from this particular experiment, as well as contribute to an understanding of fox brains in general. In addition, this can serve as a resource for comparative neuroscience and investigations into neuroanatomical variation among the family Canidae, the order Carnivora, and mammals more broadly.
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Affiliation(s)
| | - Munawwar Abdulla
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Ave, Cambridge, MA, 02138, USA
| | - Sophie A Barton
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Ave, Cambridge, MA, 02138, USA
| | - Jenny M Michlich
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Ave, Cambridge, MA, 02138, USA
| | - Lyudmila N Trut
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Anna V Kukekova
- Department of Animal Sciences, College of ACES, University of Illinois at Urbana-Champaign, Urbana, USA
| | - Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Ave, Cambridge, MA, 02138, USA.
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15
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Tancredi D, Cardinali I. Being a Dog: A Review of the Domestication Process. Genes (Basel) 2023; 14:genes14050992. [PMID: 37239352 DOI: 10.3390/genes14050992] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/19/2023] [Accepted: 04/26/2023] [Indexed: 05/28/2023] Open
Abstract
The process of canine domestication represents certainly one of the most interesting questions that evolutionary biology aims to address. A "multiphase" view of this process is now accepted, with a first phase during which different groups of wolves were attracted by the anthropogenic niche and a second phase characterized by the gradual establishment of mutual relationships between wolves and humans. Here, we provide a review of dog (Canis familiaris) domestication, highlighting the ecological differences between dogs and wolves, analyzing the molecular mechanisms which seem to have influenced the affiliative behaviors first observed in Belyaev's foxes, and describing the genetics of ancient European dogs. Then, we focus on three Mediterranean peninsulas (Balkan, Iberian and Italian), which together represent the main geographic area for studying canine domestication dynamics, as it has shaped the current genetic variability of dog populations, and where a well-defined European genetic structure was pinpointed through the analysis of uniparental genetic markers and their phylogeny.
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Affiliation(s)
- Domenico Tancredi
- Department of Chemistry, Biology and Biotechnology, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Irene Cardinali
- Department of Chemistry, Biology and Biotechnology, Università degli Studi di Perugia, 06123 Perugia, Italy
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16
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Zhaoping L. Peripheral and central sensation: multisensory orienting and recognition across species. Trends Cogn Sci 2023; 27:539-552. [PMID: 37095006 DOI: 10.1016/j.tics.2023.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 02/28/2023] [Accepted: 03/10/2023] [Indexed: 04/26/2023]
Abstract
Attentional bottlenecks force animals to deeply process only a selected fraction of sensory inputs. This motivates a unifying central-peripheral dichotomy (CPD), which separates multisensory processing into functionally defined central and peripheral senses. Peripheral senses (e.g., human audition and peripheral vision) select a fraction of the sensory inputs by orienting animals' attention; central senses (e.g., human foveal vision) allow animals to recognize the selected inputs. Originally used to understand human vision, CPD can be applied to multisensory processes across species. I first describe key characteristics of central and peripheral senses, such as the degree of top-down feedback and density of sensory receptors, and then show CPD as a framework to link ecological, behavioral, neurophysiological, and anatomical data and produce falsifiable predictions.
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Affiliation(s)
- Li Zhaoping
- University of Tübingen, Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
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17
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Hecht EE, Barton SA, Rogers Flattery CN, Meza Meza A. The evolutionary neuroscience of domestication. Trends Cogn Sci 2023; 27:553-567. [PMID: 37087363 DOI: 10.1016/j.tics.2023.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 04/24/2023]
Abstract
How does domestication affect the brain? This question has broad relevance. Domesticated animals play important roles in human society, and substantial recent work has addressed the hypotheses that a domestication syndrome links phenotypes across species, including Homo sapiens. Surprisingly, however, neuroscience research on domestication remains largely disconnected from current knowledge about how and why brains change in evolution. This article aims to bridge that gap. Examination of recent research reveals some commonalities across species, but ultimately suggests that brain changes associated with domestication are complex and variable. We conclude that interactions between behavioral, metabolic, and life-history selection pressures, as well as the role the role of experience and environment, are currently largely overlooked and represent important directions for future research.
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Affiliation(s)
- Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02171, USA.
| | - Sophie A Barton
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02171, USA
| | | | - Araceli Meza Meza
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA 02171, USA
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18
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Berns GS. Deciphering the dog brain with fMRI. Trends Neurosci 2023; 46:173-175. [PMID: 36307232 DOI: 10.1016/j.tins.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 10/04/2022] [Indexed: 01/09/2023]
Abstract
fMRI has been increasingly used to study brain function in domestic dogs trained to lie still in MRI scanners. These studies highlight both similarities and differences between dogs and humans when presented with the same stimuli, raising intriguing questions about the concept of functional homologies in a coevolved species that shares the human environment.
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19
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Healy SD. Adding the neuro to cognition: from food storing to nest building. Anim Cogn 2023; 26:249-260. [PMID: 36482117 PMCID: PMC9876861 DOI: 10.1007/s10071-022-01725-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 11/18/2022] [Accepted: 11/24/2022] [Indexed: 12/13/2022]
Abstract
Typically, investigations of animal cognition couple careful experimental manipulations with examination of the animal's behavioural responses. Sometimes those questions have included attempts to describe the neural underpinnings of the behavioural outputs. Over the past 25 years, behaviours that involve spatial learning and memory (such as navigation and food storing) has been one context in which such dual or correlated investigations have been both accessible and productive. Here I review some of that work and where it has led. Because of the wealth of data and insights gained from that work and song learning before it, it seems that it might also be useful to try to add some neurobiology to other systems in animal cognition. I finish then, with a description of recent work on the cognition and neurobiology of avian nest building. It is still relatively early days but asking questions about the cognition of nest building has already shown both neural correlates of nest building and that learning and memory play a much greater role in this behaviour than previously considered. While it is not yet clear how putting these components together will be synergistic, the examples of song learning and food storing provide encouragement. Perhaps this might be true for other behaviours too?
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Affiliation(s)
- Susan D Healy
- Centre for Biological Diversity, School of Biology, University of St Andrews, St Andrews, KY16 9TH, UK.
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20
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Junttila S, Valros A, Mäki K, Väätäjä H, Reunanen E, Tiira K. Breed differences in social cognition, inhibitory control, and spatial problem-solving ability in the domestic dog (Canis familiaris). Sci Rep 2022; 12:22529. [PMID: 36581704 PMCID: PMC9800387 DOI: 10.1038/s41598-022-26991-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 12/22/2022] [Indexed: 12/31/2022] Open
Abstract
The extraordinary genetic and behavioural diversity of dog breeds provides a unique opportunity for investigating the heritability of cognitive traits, such as problem-solving ability, social cognition, inhibitory control, and memory. Previous studies have mainly investigated cognitive differences between breed groups, and information on individual dog breeds is scarce. As a result, findings are often contradictory and inconsistent. The aim of this study was to provide more clarity on between-breed differences of cognitive traits in dogs. We examined the performance of 13 dog breeds (N = 1002 dogs) in a standardized test battery. Significant breed differences were found for understanding of human communicative gestures, following a human's misleading gesture, spatial problem-solving ability in a V-detour task, inhibitory control in a cylinder test, and persistence and human-directed behaviour during an unsolvable task. Breeds also differed significantly in their behaviour towards an unfamiliar person, activity level, and exploration of a novel environment. No significant differences were identified in tasks measuring memory or logical reasoning. Breed differences thus emerged mainly in tasks measuring social cognition, problem-solving, and inhibitory control. Our results suggest that these traits may have come under diversifying artificial selection in different breeds. These results provide a deeper understanding on breed-specific traits in dogs.
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Affiliation(s)
- Saara Junttila
- grid.7737.40000 0004 0410 2071Department of Production Animal Medicine, University of Helsinki, 00014 Helsinki, Finland
| | - Anna Valros
- grid.7737.40000 0004 0410 2071Department of Production Animal Medicine, University of Helsinki, 00014 Helsinki, Finland
| | | | - Heli Väätäjä
- grid.448926.50000 0004 4649 1976Digital Solutions, Lapland University of Applied Sciences, Jokiväylä 11C, 96300 Rovaniemi, Finland
| | - Elisa Reunanen
- grid.1374.10000 0001 2097 1371Department of Finnish and Finno-Ugric Languages, University of Turku, 20014 Turku, Finland
| | - Katriina Tiira
- smartDOG Ltd, 05800 Hyvinkää, Finland ,grid.7737.40000 0004 0410 2071Department of Equine and Small Animal Medicine, University of Helsinki, 00014 Helsinki, Finland
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21
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Dutrow EV, Serpell JA, Ostrander EA. Domestic dog lineages reveal genetic drivers of behavioral diversification. Cell 2022; 185:4737-4755.e18. [PMID: 36493753 PMCID: PMC10478034 DOI: 10.1016/j.cell.2022.11.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 09/06/2022] [Accepted: 10/31/2022] [Indexed: 12/13/2022]
Abstract
Selective breeding of domestic dogs has generated diverse breeds often optimized for performing specialized tasks. Despite the heritability of breed-typical behavioral traits, identification of causal loci has proven challenging due to the complexity of canine population structure. We overcome longstanding difficulties in identifying genetic drivers of canine behavior by developing a framework for understanding relationships between breeds and the behaviors that define them, utilizing genetic data for over 4,000 domestic, semi-feral, and wild canids and behavioral survey data for over 46,000 dogs. We identify ten major canine genetic lineages and their behavioral correlates and show that breed diversification is predominantly driven by non-coding regulatory variation. We determine that lineage-associated genes converge in neurodevelopmental co-expression networks, identifying a sheepdog-associated enrichment for interrelated axon guidance functions. This work presents a scaffold for canine diversification that positions the domestic dog as an unparalleled system for revealing the genetic origins of behavioral diversity.
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Affiliation(s)
- Emily V Dutrow
- Cancer Genetics and Comparative Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - James A Serpell
- Department of Clinical Sciences and Advanced Medicine, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA 19104, USA
| | - Elaine A Ostrander
- Cancer Genetics and Comparative Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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22
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Hopkins WD, Mulholland MM, Mareno MC, Webb SJN, Schapiro SJ. Neuroanatomical correlates of individual differences in the object choice task in chimpanzees ( Pan troglodytes). Front Psychol 2022; 13:1057722. [PMID: 36507015 PMCID: PMC9732552 DOI: 10.3389/fpsyg.2022.1057722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 10/25/2022] [Indexed: 11/26/2022] Open
Abstract
Declarative and imperative joint attention or joint engagement are important milestones in human infant development. These have been shown to be a significant predictor of later language development and are impaired in some individuals with, or at risk for, a diagnosis of autism spectrum disorder. Comparatively, while chimpanzees and other great apes have been reported to engage in imperative joint attention, evidence of declarative joint attention remains unclear based on existing studies. Some have suggested that differences in methods of assessing joint attention may have an influence on performance in nonhuman primates. Here, we report data on a measure of receptive joint attention (object choice task) in a sample of captive chimpanzees. Chimpanzees, as a group, performed significantly better than chance. By contrast, when considering individual performance, there was no significant difference in the number of those who passed and those who failed. Using quantitative genetic analyses, we found that performance on the object choice task was not significantly heritable nor were there any significant effects of sex, rearing history, or colony. Lastly, we found significant differences in gray matter covariation, between those who passed or failed the task. Those who passed contributed more to gray matter covariation in several brain regions within the social brain network, consistent with hypotheses regarding the importance of these regions in human and nonhuman primate social cognition.
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Affiliation(s)
- William D. Hopkins
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, United States,*Correspondence: William D. Hopkins,
| | - Michele M. Mulholland
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, United States
| | - Mary Catherine Mareno
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, United States
| | - Sarah J. Neal Webb
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, United States
| | - Steven J. Schapiro
- Department of Comparative Medicine, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, United States,Department of Experimental Medicine, University of Copenhagen, Copenhagen, Denmark
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23
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Fischer C, Schaub S, Büttner K, Hartmann K, Schmidt MJ. Dilated perivascular spaces can present incidental CSF-isointense foci within the ventral forebrain of dogs and cats in transverse MR images. Front Vet Sci 2022; 9:1002836. [PMID: 36299637 PMCID: PMC9590410 DOI: 10.3389/fvets.2022.1002836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 09/23/2022] [Indexed: 11/04/2022] Open
Abstract
Objective Virchow-Robin-Spaces (VRS) are cerebrospinal fluid (CSF)-containing perivascular spaces encompassing brain vessels while coursing through the parenchyma. VRS can enlarge and become visible in magnetic resonance imaging (MRI). While dilatated VRS are mostly incidental findings, they were associated with degenerative brain disease in humans. This study aimed to evaluate their occurrence and MRI morphology within the ventral forebrain of structurally normal canine and feline brains and physiological cerebrospinal fluid analysis. Sample Retro- and prospective, observational study reviewing medical records of client-owned dogs and cats which underwent MRI brain scans for unrelated reasons between 2011 and 2021. We comprised studies with various magnetic field strengths (1 Tesla/3 Tesla). Out of 2500 brain scans, three hundred thirty-five patients (293 dogs, 42 cats) presented with absent intracranial pathology and physiological CSF analysis and were included. Procedure The ventral forebrain of the included animals was assessed for bi- or unilateral CSF-isointense foci in the transverse plane. Statistical correlations were evaluated between dilated VRS presence, field strength, age, gender, weight, and cranium conformation. Additionally, a post-mortem histopathologic analysis of one dog and one cat showing dilated VRS on MRI was performed to confirm perforating arteries in the gray matter of the ventral forebrain. Results 57% of patients presented dilated VRS (N = 191: 170 dogs, 21 cats). 43% did not display dilated VRS (control group; N = 144: 123 dogs, 21 cats). A significant relation between increased magnetic field strength and detection of dilated VRS was observed in dogs; there was a 2.4 increase (p = 0.0001) in detection using 3 Tesla vs. 1 Tesla. There was a 2.4-fold increase in dilated VRS occurrence in male dogs compared to female dogs. Detection also increased with the rise of body weight. We detected no statistically significant difference between dilated VRS and the control group in age, species or cranium conformation. Conclusion and Clinical Relevance Dilated VRS can be seen within the ventral forebrain at the level of the rostral commissure on transverse MR images as symmetrical or unilateral, dot-like, CSF-isointense areas. Understanding their signal intensity features and localization prevents misinterpretation and helps differentiate them from various pathological conditions.
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Affiliation(s)
- Carolin Fischer
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Surgery, Justus-Liebig-University Giessen, Giessen, Germany,*Correspondence: Carolin Fischer
| | - Sebastian Schaub
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Surgery, Justus-Liebig-University Giessen, Giessen, Germany
| | - Kathrin Büttner
- Department for Biomathematics and Data Processing, Justus-Liebig-University Giessen, Giessen, Germany
| | | | - Martin Jürgen Schmidt
- Department of Veterinary Clinical Sciences, Clinic for Small Animals, Neurosurgery, Neuroradiology and Clinical Neurology, Justus-Liebig-University Giessen, Giessen, Germany
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24
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Eyre AW, Zapata I, Hare E, Lee KMN, Bellis C, Essler JL, Otto CM, Serpell JA, Alvarez CE. Genome scanning of behavioral selection in a canine olfactory detection breeding cohort. Sci Rep 2022; 12:14984. [PMID: 36056154 PMCID: PMC9440224 DOI: 10.1038/s41598-022-18698-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/17/2022] [Indexed: 11/13/2022] Open
Abstract
Research on working dogs is growing rapidly due to increasing global demand. Here we report genome scanning of the risk of puppies being eliminated for behavioral reasons prior to entering the training phase of the US Transportation Security Administration's (TSA) canine olfactory detection breeding and training program through 2013. Elimination of dogs for behavioral rather than medical reasons was based on evaluations at three, six, nine and twelve months after birth. Throughout that period, the fostered dogs underwent standardized behavioral tests at TSA facilities, and, for a subset of tests, dogs were tested in four different environments. Using methods developed for family studies, we performed a case-control genome wide association study (GWAS) of elimination due to behavioral observation and testing results in a cohort of 528 Labrador Retrievers (2002-2013). We accounted for relatedness by including the pedigree as a covariate and maximized power by including individuals with phenotype, but not genotype, data (approximately half of this cohort). We determined genome wide significance based on Bonferroni adjustment of two quasi-likelihood score tests optimized for either small or nearly-fully penetrant effect sizes. Six loci were significant and five suggestive, with approximately equal numbers of loci for the two tests and frequencies of loci with single versus multiple mapped markers. Several loci implicate a single gene, including CHD2, NRG3 and PDE1A which have strong relevance to behavior in humans and other species. We briefly discuss how expanded studies of canine breeding programs could advance understanding of learning and performance in the mammalian life course. Although human interactions and other environmental conditions will remain critical, our findings suggest genomic breeding selection could help improve working dog populations.
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Affiliation(s)
- Alexander W Eyre
- Center for Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, 43205, USA
| | - Isain Zapata
- Department of Biomedical Sciences, Rocky Vista University College of Osteopathic Medicine, Parker, CO, 80134, USA
| | | | - Katharine M N Lee
- Division of Public Health Sciences, Department of Surgery, Washington University in St. Louis School of Medicine, St. Louis, USA
- Department of Anthropology, Tulane University, New Orleans, USA
| | - Claire Bellis
- Human Genomics, Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, 138672, Singapore
- Centre for Genomics and Personalised Health, Genomics Research Centre, School of Biomedical Sciences, Queensland University of Technology (QUT), Kelvin Grove, QLD, Australia
| | - Jennifer L Essler
- Penn Vet Working Dog Center, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19146, USA
- Department of Animal Science, State University of New York College of Agriculture and Technology at Cobleskill, New York, USA
| | - Cynthia M Otto
- Penn Vet Working Dog Center, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19146, USA
| | - James A Serpell
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Carlos E Alvarez
- Center for Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, 43205, USA.
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, 43210, USA.
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25
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Extensive Connections of the Canine Olfactory Pathway Revealed by Tractography and Dissection. J Neurosci 2022; 42:6392-6407. [PMID: 35817576 PMCID: PMC9398547 DOI: 10.1523/jneurosci.2355-21.2022] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 06/28/2022] [Accepted: 06/30/2022] [Indexed: 11/21/2022] Open
Abstract
The olfactory sense of the domestic dog is widely recognized as being highly sensitive with a diverse function; however, little is known about the structure of its olfactory system. This study examined a cohort of mixed-sex mesaticephalic canines and used diffusion tensor imaging (DTI), an MRI technique, to map connections from the olfactory bulb to other cortical regions of the brain. The results were validated using the Klingler dissection method. An extensive pathway composed of five white matter tracts connecting to the occipital lobe, cortical spinal tract, limbic system, piriform lobe, and entorhinal pathway was identified. This is the first documentation of a direct connection between the olfactory bulb and occipital lobe in any species and is a step toward further understanding how the dog integrates olfactory stimuli into their cognitive function.SIGNIFICANCE STATEMENT The highly sensitive olfactory system of the domestic dog is largely unexplored. We applied diffusion tractography and dissection techniques to evaluate the white matter connections associated with the olfactory system in a large cohort of dogs. We discovered an extensive white matter network extending from the olfactory bulb to form novel connections directly to other cortices of the brain. This is the first documentation of these novel olfactory connections and provides new insight into how dogs integrate olfactory stimuli in their cognitive functioning.
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26
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Ferrando E, Dahl CD. An investigation on the olfactory capabilities of domestic dogs (Canis lupus familiaris). Anim Cogn 2022; 25:1567-1577. [PMID: 35689114 DOI: 10.1007/s10071-022-01640-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/16/2022] [Accepted: 05/19/2022] [Indexed: 11/26/2022]
Abstract
The extraordinary olfactory capabilities in detection and rescue dogs are well-known. However, the olfactory performance varies by breed and search environment (Jezierski et al. in Forensic Sci Int 237:112-118, 2014), as well as by the quantity of training (Horowitz et al. in Learn Motivation 44(4):207-217, 2013). While detection of an olfactory cue inherently demands a judgment regarding the presence or absence of a cue at a given location, olfactory discrimination requires an assessment of quantity, a task demanding more attention and, hence, decreasing reliability as an informational source (Horowitz et al. 2013). This study aims at gaining more clarity on detection and discrimination of olfactory cues in untrained dogs and in a variety of dog breeds. Using a two-alternative forced choice (2AFC) paradigm, we assessed olfactory detection scores by presenting a varied quantity of food reward under one or the other hidden cup, and discrimination scores by presenting two varied quantities of food reward under both hidden cups. We found relatively reliable detection performances across all breeds and limited discrimination abilities, modulated by breed. We discuss our findings in relation to the cognitive demands imposed by the tasks and the cephalic index of the dog breeds.
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Affiliation(s)
- Elodie Ferrando
- Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
- MTA-ELTE 'Lendület' Neuroethology of Communication Research Group, Eötvös Loránd University, Pázmány Péter sétány 1/C, Budapest, 1117, Hungary
- Department of Ethology, Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, Budapest, 1117, Hungary
| | - Christoph D Dahl
- Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.
- Graduate Institute of Mind, Brain and Consciousness, Taipei Medical University, Taipei, Taiwan.
- Brain and Consciousness Research Centre, Taipei Medical University Shuang-Ho Hospital, New Taipei City, Taiwan.
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27
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A Middle Pleistocene wolf from central Italy provides insights on the first occurrence of Canis lupus in Europe. Sci Rep 2022; 12:2882. [PMID: 35217686 PMCID: PMC8881584 DOI: 10.1038/s41598-022-06812-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/27/2022] [Indexed: 12/30/2022] Open
Abstract
Here, we describe a partial cranium of a large canid dated at 406.5 ± 2.4 ka from the Middle Pleistocene of Ponte Galeria (Rome, Italy). The sample represents one of the few Middle Pleistocene remains of a wolf-like canid falling within the timeframe when the Canis mosbachensis–Canis lupus transition occurred, a key moment to understand the spread of the extant wolf (Canis lupus) in Europe. CT-based methods allow studying the outer and inner cranial anatomy (brain and frontal sinuses) of a selected sample of fossil and extant canids. Morphological and biometric results allowed to: (I) ascribe the cranium from Ponte Galeria to an adult Canis lupus, representing the first reliable occurrence of this taxon in Europe; (II) provide the content for a biochronological revision of the Middle Pleistocene record of European wolves.
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28
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Cuaya LV, Hernández-Pérez R, Boros M, Deme A, Andics A. Speech naturalness detection and language representation in the dog brain. Neuroimage 2021; 248:118811. [PMID: 34906714 DOI: 10.1016/j.neuroimage.2021.118811] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 12/11/2022] Open
Abstract
Family dogs are exposed to a continuous flow of human speech throughout their lives. However, the extent of their abilities in speech perception is unknown. Here, we used functional magnetic resonance imaging (fMRI) to test speech detection and language representation in the dog brain. Dogs (n = 18) listened to natural speech and scrambled speech in a familiar and an unfamiliar language. Speech scrambling distorts auditory regularities specific to speech and to a given language, but keeps spectral voice cues intact. We hypothesized that if dogs can extract auditory regularities of speech, and of a familiar language, then there will be distinct patterns of brain activity for natural speech vs. scrambled speech, and also for familiar vs. unfamiliar language. Using multivoxel pattern analysis (MVPA) we found that bilateral auditory cortical regions represented natural speech and scrambled speech differently; with a better classifier performance in longer-headed dogs in a right auditory region. This neural capacity for speech detection was not based on preferential processing for speech but rather on sensitivity to sound naturalness. Furthermore, in case of natural speech, distinct activity patterns were found for the two languages in the secondary auditory cortex and in the precruciate gyrus; with a greater difference in responses to the familiar and unfamiliar languages in older dogs, indicating a role for the amount of language exposure. No regions represented differently the scrambled versions of the two languages, suggesting that the activity difference between languages in natural speech reflected sensitivity to language-specific regularities rather than to spectral voice cues. These findings suggest that separate cortical regions support speech naturalness detection and language representation in the dog brain.
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Affiliation(s)
- Laura V Cuaya
- Department of Ethology, Institute of Biology, Eötvös Loránd University, Budapest, Hungary; MTA-ELTE 'Lendület' Neuroethology of Communication Research Group, Hungarian Academy of Sciences - Eötvös Loránd University, Budapest, Hungary.
| | - Raúl Hernández-Pérez
- Department of Ethology, Institute of Biology, Eötvös Loránd University, Budapest, Hungary; MTA-ELTE 'Lendület' Neuroethology of Communication Research Group, Hungarian Academy of Sciences - Eötvös Loránd University, Budapest, Hungary
| | - Marianna Boros
- Department of Ethology, Institute of Biology, Eötvös Loránd University, Budapest, Hungary; MTA-ELTE 'Lendület' Neuroethology of Communication Research Group, Hungarian Academy of Sciences - Eötvös Loránd University, Budapest, Hungary
| | - Andrea Deme
- Department of Applied Linguistics and Phonetics, Faculty of Humanities, Eötvös Loránd University, Budapest, Hungary; MTA-ELTE 'Lendület' Lingual Articulation Research Group, Budapest, Hungary
| | - Attila Andics
- Department of Ethology, Institute of Biology, Eötvös Loránd University, Budapest, Hungary; MTA-ELTE 'Lendület' Neuroethology of Communication Research Group, Hungarian Academy of Sciences - Eötvös Loránd University, Budapest, Hungary
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29
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Benítez-Burraco A, Pörtl D, Jung C. Did Dog Domestication Contribute to Language Evolution? Front Psychol 2021; 12:695116. [PMID: 34589022 PMCID: PMC8473740 DOI: 10.3389/fpsyg.2021.695116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 08/02/2021] [Indexed: 11/20/2022] Open
Abstract
Different factors seemingly account for the emergence of present-day languages in our species. Human self-domestication has been recently invoked as one important force favoring language complexity mostly via a cultural mechanism. Because our self-domestication ultimately resulted from selection for less aggressive behavior and increased prosocial behavior, any evolutionary or cultural change impacting on aggression levels is expected to have fostered this process. Here, we hypothesize about a parallel domestication of humans and dogs, and more specifically, about a positive effect of our interaction with dogs on human self-domestication, and ultimately, on aspects of language evolution, through the mechanisms involved in the control of aggression. We review evidence of diverse sort (ethological mostly, but also archeological, genetic, and physiological) supporting such an effect and propose some ways of testing our hypothesis.
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Affiliation(s)
- Antonio Benítez-Burraco
- Department of Spanish, Linguistics, and Theory of Literature (Linguistics), Faculty of Philology, University of Seville, Seville, Spain
| | - Daniela Pörtl
- Psychiatric Department, Saale-Unstrut Klinikum, Teaching Hospital Leipzig and Jena Universities, Naumburg, Germany
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30
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Hecht EE, Zapata I, Alvarez CE, Gutman DA, Preuss TM, Kent M, Serpell JA. Neurodevelopmental scaling is a major driver of brain-behavior differences in temperament across dog breeds. Brain Struct Funct 2021; 226:2725-2739. [PMID: 34455497 DOI: 10.1007/s00429-021-02368-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/23/2021] [Indexed: 11/24/2022]
Abstract
Behavioral traits like aggression, anxiety, and trainability differ significantly across dog breeds and are highly heritable. However, the neural bases of these differences are unknown. Here we analyzed structural MRI scans of 62 dogs in relation to breed-average scores for the 14 major dimensions in the Canine Behavioral Assessment and Research Questionnaire, a well-validated measure of canine temperament. Several behavior categories showed significant relationships with morphologically covarying gray matter networks and regional volume changes. Networks involved in social processing and the flight-or-fight response were associated with stranger-directed fear and aggression, putatively the main behaviors under selection pressure during wolf-to-dog domestication. Trainability was significantly associated with expansion in broad regions of cortex, while fear, aggression, and other "problem" behaviors were associated with expansion in distributed subcortical regions. These results closely overlapped with regional volume changes with total brain size, in striking correspondence with models of developmental constraint on brain evolution. This suggests that the established link between dog body size and behavior is due at least in part to disproportionate enlargement of later-developing regions in larger brained dogs. We discuss how this may explain the known correlation of increasing reactivity with decreasing body size in dogs.
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Affiliation(s)
- E E Hecht
- Department of Human Evolutionary Biology, Harvard University, 11 Divinity Ave., Cambridge, MA, 02138, USA.
| | - I Zapata
- Department of Biomedical Sciences, Rocky Vista University, Parker, CO, 80134, USA
| | - C E Alvarez
- Center for Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, 43205, USA.,Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, 43210, USA.,Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine, Columbus, OH, 43210, USA
| | - D A Gutman
- Department of Neurology, School of Medicine, Emory University, Atlanta, GA, 30029, USA
| | - T M Preuss
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, 30029, USA
| | - M Kent
- College of Veterinary Medicine, University of Georgia at Athens, Athens, GA, 30602, USA
| | - J A Serpell
- Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
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31
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Johnsson M, Henriksen R, Wright D. The neural crest cell hypothesis: no unified explanation for domestication. Genetics 2021; 219:iyab097. [PMID: 34849908 PMCID: PMC8633120 DOI: 10.1093/genetics/iyab097] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 02/11/2021] [Indexed: 12/03/2022] Open
Affiliation(s)
- Martin Johnsson
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala 750 07, Sweden
| | - Rie Henriksen
- IFM Biology, Linköping University, Linköping 58183, Sweden
| | - Dominic Wright
- IFM Biology, Linköping University, Linköping 58183, Sweden
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32
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Shan S, Xu F, Brenig B. Genome-Wide Association Studies Reveal Neurological Genes for Dog Herding, Predation, Temperament, and Trainability Traits. Front Vet Sci 2021; 8:693290. [PMID: 34368281 PMCID: PMC8335642 DOI: 10.3389/fvets.2021.693290] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 06/15/2021] [Indexed: 11/13/2022] Open
Abstract
Genome-wide association study (GWAS) using dog breed standard values as phenotypic measurements is an efficient way to identify genes associated with morphological and behavioral traits. As a result of strong human purposeful selections, several specialized behavioral traits such as herding and hunting have been formed in different modern dog breeds. However, genetic analyses on this topic are rather limited due to the accurate phenotyping difficulty for these complex behavioral traits. Here, 268 dog whole-genome sequences from 130 modern breeds were used to investigate candidate genes underlying dog herding, predation, temperament, and trainability by GWAS. Behavioral phenotypes were obtained from the American Kennel Club based on dog breed standard descriptions or groups (conventional categorization of dog historical roles). The GWAS results of herding behavior (without body size as a covariate) revealed 44 significantly associated sites within five chromosomes. Significantly associated sites on CFA7, 9, 10, and 20 were located either in or near neuropathological or neuronal genes including THOC1, ASIC2, MSRB3, LLPH, RFX8, and CHL1. MSRB3 and CHL1 genes were reported to be associated with dog fear. Since herding is a restricted hunting behavior by removing killing instinct, 36 hounds and 55 herding dogs were used to analyze predation behavior. Three neuronal-related genes (JAK2, MEIS1, and LRRTM4) were revealed as candidates for predation behavior. The significantly associated variant of temperament GWAS was located within ACSS3 gene. The highest associated variant in trainability GWAS is located on CFA22, with no variants detected above the Bonferroni threshold. Since dog behaviors are correlated with body size, we next incorporate body mass as covariates into GWAS; and significant signals around THOC1, MSRB3, LLPH, RFX8, CHL1, LRRTM4, and ACSS3 genes were still detected for dog herding, predation, and temperament behaviors. In humans, these candidate genes are either involved in nervous system development or associated with mental disorders. In conclusion, our results imply that these neuronal or psychiatric genes might be involved in biological processes underlying dog herding, predation, and temperament behavioral traits.
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Affiliation(s)
- Shuwen Shan
- Department of Animal Sciences, Faculty of Agricultural Sciences, Institute of Veterinary Medicine, University of Goettingen, Göttingen, Germany
| | - Fangzheng Xu
- Department of Animal Sciences, Faculty of Agricultural Sciences, Institute of Veterinary Medicine, University of Goettingen, Göttingen, Germany
| | - Bertram Brenig
- Department of Animal Sciences, Faculty of Agricultural Sciences, Institute of Veterinary Medicine, University of Goettingen, Göttingen, Germany
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33
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Karl S, Sladky R, Lamm C, Huber L. Neural Responses of Pet Dogs Witnessing Their Caregiver's Positive Interactions with a Conspecific: An fMRI Study. Cereb Cortex Commun 2021; 2:tgab047. [PMID: 34447934 PMCID: PMC8382916 DOI: 10.1093/texcom/tgab047] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 11/13/2022] Open
Abstract
We have limited knowledge on how dogs perceive humans and their actions. Various researchers investigated how they process human facial expressions, but their brain responses to complex social scenarios remain unclear. While undergoing fMRI, we exposed pet dogs to videos showing positive social and neutral nonsocial interactions between their caregivers and another conspecific. Our main interest was how the dogs responded to their caregivers (compared to a stranger) engaging in a pleasant interaction with another dog that could be seen as social rival. We hypothesized that the dogs would show activation increases in limbic areas such as the amygdala, hypothalamus, and insula and likely show higher attention and arousal during the positive caregiver-dog interaction. When contrasting the social with the nonsocial interaction, we found increased activations in the left amygdala and the insular cortex. Crucially, the dogs' hypothalamus showed strongest activation when the caregiver engaged in a positive social interaction. These findings indicate that dogs are sensitive to social affective human-dog interactions and likely show higher valence attribution and arousal in a situation possibly perceived as a potential threat to their caregiver bonds. Our study provides a first window into the neural correlates of social and emotional processing in dogs.
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Affiliation(s)
- Sabrina Karl
- Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna, University of Vienna, 1210 Vienna, Austria
| | - Ronald Sladky
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, 1010 Vienna, Austria
| | - Claus Lamm
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, 1010 Vienna, Austria
| | - Ludwig Huber
- Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna, University of Vienna, 1210 Vienna, Austria
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34
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Hecht EE, Kukekova AV, Gutman DA, Acland GM, Preuss TM, Trut LN. Neuromorphological Changes following Selection for Tameness and Aggression in the Russian Farm-Fox experiment. J Neurosci 2021; 41:6144-6156. [PMID: 34127519 PMCID: PMC8276742 DOI: 10.1523/jneurosci.3114-20.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 05/11/2021] [Accepted: 05/17/2021] [Indexed: 01/13/2023] Open
Abstract
The Russian farm-fox experiment is an unusually long-running and well-controlled study designed to replicate wolf-to-dog domestication. As such, it offers an unprecedented window onto the neural mechanisms governing the evolution of behavior. Here we report evolved changes to gray matter morphology resulting from selection for tameness versus aggressive responses toward humans in a sample of 30 male fox brains. Contrasting with standing ideas on the effects of domestication on brain size, tame foxes did not show reduced brain volume. Rather, gray matter volume in both the tame and aggressive strains was increased relative to conventional farm foxes bred without deliberate selection on behavior. Furthermore, tame- and aggressive-enlarged regions overlapped substantially, including portions of motor, somatosensory, and prefrontal cortex, amygdala, hippocampus, and cerebellum. We also observed differential morphologic covariation across distributed gray matter networks. In one prefrontal-cerebellum network, this covariation differentiated the three populations along the tame-aggressive behavioral axis. Surprisingly, a prefrontal-hypothalamic network differentiated the tame and aggressive foxes together from the conventional strain. These findings indicate that selection for opposite behaviors can influence brain morphology in a similar way.SIGNIFICANCE STATEMENT Domestication represents one of the largest and most rapid evolutionary shifts of life on earth. However, its neural correlates are largely unknown. Here we report the neuroanatomical consequences of selective breeding for tameness or aggression in the seminal Russian farm-fox experiment. Compared with a population of conventional farm-bred control foxes, tame foxes show neuroanatomical changes in the PFC and hypothalamus, paralleling wolf-to-dog shifts. Surprisingly, though, aggressive foxes also show similar changes. Moreover, both strains show increased gray matter volume relative to controls. These results indicate that similar brain adaptations can result from selection for opposite behavior, that existing ideas of brain changes in domestication may need revision, and that significant neuroanatomical change can evolve very quickly, within the span of <100 generations.
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Affiliation(s)
- Erin E Hecht
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138
| | - Anna V Kukekova
- Department of Animal Sciences, College of Agriculture, Consumer, and Environmental Sciences, University of IL Urbana-Champaign, Urbana, IL 61801
| | | | - Gregory M Acland
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, 14853
| | - Todd M Preuss
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322
| | - Lyudmila N Trut
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia, 630090
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35
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Balcarcel AM, Veitschegger K, Clauss M, Sánchez-Villagra MR. Intensive human contact correlates with smaller brains: differential brain size reduction in cattle types. Proc Biol Sci 2021; 288:20210813. [PMID: 34102890 PMCID: PMC8188006 DOI: 10.1098/rspb.2021.0813] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 05/17/2021] [Indexed: 12/30/2022] Open
Abstract
Cattle are one of the most intensively bred domestic animals, providing humans with a multitude of products and uses. Using data from the fossil record, we test if their domestication, as for other taxa, has resulted in a reduction of their brain size. We not only conclude that Bos taurus (domestic cattle) have smaller brains than their wild ancestor, Bos primigenius (aurochs), but that brain size varies significantly by breed, with some having much smaller brains than others. Differences in husbandry practices between several breed categories align with a range of human engagement, which also aligns with the degree of selection for docility. Sampling 317 domestics from 71 breeds, we investigate if differences in brain size correlate with the intensity of human contact. A clear pattern emerges whereby a brain reduction gradient parallels a gradient in behavioural selection. Bullfighting cattle, which are bred for fighting and aggressive temperament, have much larger brains than dairy breeds, which are intensively selected for docility. Our results add to a fundamental aspect of animal domestication theory: the interplay between basic features of the domestic environment-selection for docility, absence of predators and human provision of resources-seems to explain differences in brain size.
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Affiliation(s)
- A. M. Balcarcel
- Palaeontological Institute and Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland
| | - K. Veitschegger
- Palaeontological Institute and Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland
| | - M. Clauss
- Clinic for Zoo Animals, Exotic Pets and Wildlife, University of Zurich, Winterthurerstrasse 260, 8057 Zurich, Switzerland
| | - M. R. Sánchez-Villagra
- Palaeontological Institute and Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland
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36
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Saganuwan SA. Modified formulas for calculation of encephalization: quotient in dogs. BMC Res Notes 2021; 14:223. [PMID: 34082832 PMCID: PMC8176606 DOI: 10.1186/s13104-021-05638-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 05/26/2021] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE Dogs are a breed of animals that play important roles in security service, companionship, hunting, guard, work and models of research for application in humans. Intelligence is the key factor to success in life, most especially for dogs that are used for security purposes at the airports, seaports, public places, houses, schools and farms. However, it has been reported that there is correlation between intelligence, body weight, height and craniometry in human. In view of this, literatures were searched on body weight, height and body surface areas of ten dogs with intent to determining their comparative level of intelligence using encephalization quotient. RESULTS Findings revealed that dogs have relationship of brain allometry with human as proven by encephalization quotient [Formula: see text] and Brain Mass (E) = kpβ, where p is the body weight; k = 0.14 and β = 0.528, respectively. Saganuwa's formula yielded better results as compared with the other formulas. Dogs with body surface area (BSA), weight and height similar to that of human are the most intelligent. Doberman pinscher is the most intelligent followed by German shepherd, Labrador retriever, Golden retriever, respectively.
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Affiliation(s)
- Saganuwan Alhaji Saganuwan
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Federal University of Agriculture, Benue State, P.M.B. 2373, Makurdi, Nigeria.
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37
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Man's best friend in life and death: scientific perspectives and challenges of dog brain banking. GeroScience 2021; 43:1653-1668. [PMID: 33970413 PMCID: PMC8492856 DOI: 10.1007/s11357-021-00373-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 04/19/2021] [Indexed: 12/12/2022] Open
Abstract
Biobanking refers to the systematic collection, storage, and distribution of pre- or post-mortem biological samples derived from volunteer donors. The demand for high-quality human specimens is clearly demonstrated by the number of newly emerging biobanking facilities and large international collaborative networks. Several animal species are relevant today in medical research; therefore, similar initiatives in comparative physiology could be fruitful. Dogs, in particular, are gaining increasing attention in translational research on complex phenomena, like aging, cancer, and neurodegenerative diseases. Therefore, biobanks gathering and storing dog biological materials together with related data could play a vital role in translational and veterinary research projects. To achieve these aims, a canine biobank should meet the same standards in sample quality and data management as human biobanks and should rely on well-designed collaborative networks between different professionals and dog owners. While efforts to create dog biobanks could face similar financial and technical challenges as their human counterparts, they can widen the spectrum of successful collaborative initiatives towards a better picture of dogs’ physiology, disease, evolution, and translational potential. In this review, we provide an overview about the current state of dog biobanking and introduce the “Canine Brain and Tissue Bank” (CBTB)—a new, large-scale collaborative endeavor in the field.
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Barry EF, Loftus JP, Luh WM, de Leon MJ, Niogi SN, Johnson PJ. Diffusion tensor-based analysis of white matter in the healthy aging canine brain. Neurobiol Aging 2021; 105:129-136. [PMID: 34062488 DOI: 10.1016/j.neurobiolaging.2021.04.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 12/14/2022]
Abstract
White matter dysfunction and degeneration have been a topic of great interest in healthy and pathological aging. While ex vivo studies have investigated age-related changes in canines, little in vivo canine aging research exists. Quantitative diffusion MRI such as diffusion tensor imaging (DTI) has demonstrated aging and neurodegenerative white matter changes in humans. However, this method has not been applied and adapted in vivo to canine populations. This study aimed to test the hypothesis that white matter diffusion changes frequently reported in human aging are also found in aged canines. The study used Tract Based Spatial Statistics (TBSS) and a region of interest (ROI) approach to investigate age related changes in fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AxD) and radial diffusivity (RD). The results show that, compared to younger animals, aged canines have significant decreases in FA in parietal and temporal regions as well as the corpus callosum and fornix. Additionally, AxD decreases were observed in parietal, frontal, and midbrain regions. Similarly, an age- related increase in RD was observed in the right parietal lobe while MD decreases were found in the midbrain. These findings suggest that canine samples show commonalities with human brain aging as both exhibit similar white matter diffusion tensor changes with increasing age.
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Affiliation(s)
- Erica F Barry
- Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - John P Loftus
- Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Wen-Ming Luh
- National Institute on Aging, Baltimore, Maryland
| | - Mony J de Leon
- Department of Radiology, Weill Cornell Medicine, New York, NY
| | - Sumit N Niogi
- Department of Radiology, Weill Cornell Medicine, New York, NY
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39
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Hare B, Ferrans M. Is cognition the secret to working dog success? Anim Cogn 2021; 24:231-237. [PMID: 33687597 DOI: 10.1007/s10071-021-01491-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 11/27/2022]
Abstract
Dogs' special relationship with humans not only makes them ubiquitous in our lives, but working dogs specifically perform essential functions for us such as sniffing out bombs and pulling wheelchairs for the disabled. To enhance the performance of working dogs, it is essential to understand the cognitive skills that underlie and lead to their success. This review details recent work in the field of canine cognition, including how dogs have evolved socio-cognitive skills that mimic or, in some cases, rival even our closest primate relatives. We review how these findings have laid the foundation for new studies that hope to help enhance working dog programs. This includes work that has begun to reveal the development and stability of the most important traits for service work. Discoveries like these suggest the possibility of translating what we have learned to improve breeding, selection, and training for these jobs. The latest research we review here shows promise in contributing to the production of better dogs and, consequently, more help for people.
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Affiliation(s)
- Brian Hare
- Department of Evolutionary Anthropology, Duke University, Durham, USA
- Center for Cognitive Neuroscience, Duke University, Durham, USA
- Department of Psychology and Neuroscience, Duke University, Durham, USA
| | - Morgan Ferrans
- Department of Evolutionary Anthropology, Duke University, Durham, USA.
- Center for Cognitive Neuroscience, Duke University, Durham, USA.
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40
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Yamazaki K, Yoshimura A, Miyahara S, Sugi S, Itono M, Kondo M, Tsuji N, Shimizu M, Fukushima R, Kishimoto M. Evaluation of cerebral blood flow in the hippocampus, thalamus, and basal ganglia and the volume of the hippocampus in dogs before and during treatment with prednisolone. Am J Vet Res 2021; 82:230-236. [PMID: 33629902 DOI: 10.2460/ajvr.82.3.230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To examine whether glucocorticoid (GC) administration alters hippocampal cerebral blood flow (CBF) or volume in dogs. ANIMALS 6 clinically normal adult Beagles. PROCEDURES Each dog underwent CT and MRI to measure the CBF in the hippocampus, basal ganglia, thalamus, and cerebral cortex and the volume of the hippocampus in each hemisphere of the brain before (day 0) and during (days 7 and 21) a 21-day treatment with prednisolone (1.0 mg/kg, PO, q 24 h) and famotidine (0.5 mg/kg, PO, q 12 h). Results for hippocampal volume, anesthesia-related variables, and semiquantitative measurements of CBF (hemisphere-specific ratios of the CBF in the hippocampus, basal ganglia, and thalamus relative to the CBF in the ipsilateral cerebral cortex and the left cerebral cortex CBF-to-right cerebral cortex CBF ratio) were compared across assessment time points (days 0, 7, and 21). RESULTS The ratios of CBF in the right hippocampus and right thalamus to that in the right cerebral cortex on day 21 were significantly lower than those on day 0. No meaningful differences were detected in results for the hippocampal volume in either hemisphere or for the anesthesia-related variables across the 3 time points. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that GC administration reduced CBF in the hippocampus and thalamus in dogs of the present study, similar to that which occurs in humans. Research on GC-related brain alteration in dogs could potentially contribute to advancements in understanding Alzheimer disease in humans and neurodegenerative conditions in dogs.
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41
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Expanding evolutionary neuroscience: insights from comparing variation in behavior. Neuron 2021; 109:1084-1099. [PMID: 33609484 DOI: 10.1016/j.neuron.2021.02.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/25/2021] [Accepted: 01/28/2021] [Indexed: 01/01/2023]
Abstract
Neuroscientists have long studied species with convenient biological features to discover how behavior emerges from conserved molecular, neural, and circuit level processes. With the advent of new tools, from viral vectors and gene editing to automated behavioral analyses, there has been a recent wave of interest in developing new, "nontraditional" model species. Here, we advocate for a complementary approach to model species development, that is, model clade development, as a way to integrate an evolutionary comparative approach with neurobiological and behavioral experiments. Capitalizing on natural behavioral variation in and investing in experimental tools for model clades will be a valuable strategy for the next generation of neuroscience discovery.
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42
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Boch M, Karl S, Sladky R, Huber L, Lamm C, Wagner IC. Tailored haemodynamic response function increases detection power of fMRI in awake dogs (Canis familiaris). Neuroimage 2021; 224:117414. [PMID: 33011420 PMCID: PMC7616344 DOI: 10.1016/j.neuroimage.2020.117414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 08/17/2020] [Accepted: 09/24/2020] [Indexed: 01/06/2023] Open
Abstract
Functional magnetic resonance imaging (fMRI) of awake and unrestrained dogs (Canis familiaris) has been established as a novel opportunity for comparative neuroimaging, promising important insights into the evolutionary roots of human brain function and cognition. However, data processing and analysis pipelines are often derivatives of methodological standards developed for human neuroimaging, which may be problematic due to profound neurophysiological and anatomical differences between humans and dogs. Here, we explore whether dog fMRI studies would benefit from a tailored dog haemodynamic response function (HRF). In two independent experiments, dogs were presented with different visual stimuli. BOLD signal changes in the visual cortex during these experiments were used for (a) the identification and estimation of a tailored dog HRF, and (b) the independent validation of the resulting dog HRF estimate. Time course analyses revealed that the BOLD signal in the primary visual cortex peaked significantly earlier in dogs compared to humans, while being comparable in shape. Deriving a tailored dog HRF significantly improved the model fit in both experiments, compared to the canonical HRF used in human fMRI. Using the dog HRF yielded significantly increased activation during visual stimulation, extending from the occipital lobe to the caudal parietal cortex, the bilateral temporal cortex, into bilateral hippocampal and thalamic regions. In sum, our findings provide robust evidence for an earlier onset of the dog HRF in two visual stimulation paradigms, and suggest that using such an HRF will be important to increase fMRI detection power in canine neuroimaging. By providing the parameters of the tailored dog HRF and related code, we encourage and enable other researchers to validate whether our findings generalize to other sensory modalities and experimental paradigms.
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Affiliation(s)
- Magdalena Boch
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, 1010 Vienna, Austria; Department of Cognitive Biology, Faculty of Life Sciences, University of Vienna, 1090, Vienna, Austria
| | - Sabrina Karl
- Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, 1210 Vienna, Austria
| | - Ronald Sladky
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, 1010 Vienna, Austria
| | - Ludwig Huber
- Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna and University of Vienna, 1210 Vienna, Austria
| | - Claus Lamm
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, 1010 Vienna, Austria.
| | - Isabella C Wagner
- Social, Cognitive and Affective Neuroscience Unit, Department of Cognition, Emotion, and Methods in Psychology, Faculty of Psychology, University of Vienna, 1010 Vienna, Austria.
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43
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Kujala MV, Kauppi JP, Törnqvist H, Helle L, Vainio O, Kujala J, Parkkonen L. Time-resolved classification of dog brain signals reveals early processing of faces, species and emotion. Sci Rep 2020; 10:19846. [PMID: 33199715 PMCID: PMC7669855 DOI: 10.1038/s41598-020-76806-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 10/30/2020] [Indexed: 11/22/2022] Open
Abstract
Dogs process faces and emotional expressions much like humans, but the time windows important for face processing in dogs are largely unknown. By combining our non-invasive electroencephalography (EEG) protocol on dogs with machine-learning algorithms, we show category-specific dog brain responses to pictures of human and dog facial expressions, objects, and phase-scrambled faces. We trained a support vector machine classifier with spatiotemporal EEG data to discriminate between responses to pairs of images. The classification accuracy was highest for humans or dogs vs. scrambled images, with most informative time intervals of 100–140 ms and 240–280 ms. We also detected a response sensitive to threatening dog faces at 30–40 ms; generally, responses differentiating emotional expressions were found at 130–170 ms, and differentiation of faces from objects occurred at 120–130 ms. The cortical sources underlying the highest-amplitude EEG signals were localized to the dog visual cortex.
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Affiliation(s)
- Miiamaaria V Kujala
- Department of Psychology, Faculty of Education and Psychology, University of Jyväskylä, PO Box 35, 40014, Jyväskylä, Finland. .,Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, PL 57, 00014, Helsinki, Finland. .,Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, P.O. Box 12200, 00076, Aalto, Finland.
| | - Jukka-Pekka Kauppi
- Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, P.O. Box 12200, 00076, Aalto, Finland.,Faculty of Information Technology, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland
| | - Heini Törnqvist
- Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, PL 57, 00014, Helsinki, Finland
| | - Liisa Helle
- Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, P.O. Box 12200, 00076, Aalto, Finland
| | - Outi Vainio
- Department of Equine and Small Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, PL 57, 00014, Helsinki, Finland
| | - Jan Kujala
- Department of Psychology, Faculty of Education and Psychology, University of Jyväskylä, PO Box 35, 40014, Jyväskylä, Finland
| | - Lauri Parkkonen
- Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, P.O. Box 12200, 00076, Aalto, Finland
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44
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Czeibert K, Sommese A, Petneházy Ö, Csörgő T, Kubinyi E. Digital Endocasting in Comparative Canine Brain Morphology. Front Vet Sci 2020; 7:565315. [PMID: 33134351 PMCID: PMC7572857 DOI: 10.3389/fvets.2020.565315] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 09/03/2020] [Indexed: 12/03/2022] Open
Abstract
Computed tomography (CT) is one of the most useful techniques for digitizing bone structures and making endocranial models from the neurocranium. The resulting digital endocasts reflect the morphology of the brain and the associated structures. Our first aim was to document the methodology behind creating detailed digital endocasts of canine skulls. We created digital endocasts of the skulls of 24 different dog breeds and 4 wild canids for visualization and teaching purposes. We used CT scanning with 0.323 mm × 0.322 mm × 0.6 mm resolution. The imaging data were segmented with 3D Slicer software and refined with Autodesk Meshmixer. Images were visualized in 3D Slicer and surface models were converted to 3D PDFs to provide easier interactive access, and 3D prints were also generated for visualization purposes. Our second aim was to analyze how skull length and width relate to the surface areas of the prepiriform rhinencephalic, prefrontal, and non-prefrontal cerebral convexity areas of the endocasts. The rhinencephalic area ratio decreased with a larger skull index. Our results open the possibility to analyze the relationship between the skull and brain morphology, and to link certain features to behavior, and cognition in dogs.
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Affiliation(s)
- Kálmán Czeibert
- Department of Ethology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Andrea Sommese
- Department of Ethology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Örs Petneházy
- University of Kaposvár, Kaposvár, Hungary.,Medicopus Nonprofit Ltd., Kaposvár, Hungary
| | - Tibor Csörgő
- Department of Anatomy, Cell and Developmental Biology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Enikő Kubinyi
- Department of Ethology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
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45
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Comparative Brain Imaging Reveals Analogous and Divergent Patterns of Species and Face Sensitivity in Humans and Dogs. J Neurosci 2020; 40:8396-8408. [PMID: 33020215 PMCID: PMC7577605 DOI: 10.1523/jneurosci.2800-19.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 05/26/2020] [Accepted: 06/20/2020] [Indexed: 02/08/2023] Open
Abstract
Conspecific-preference in social perception is evident for multiple sensory modalities and in many species. There is also a dedicated neural network for face processing in primates. However, the evolutionary origin and the relative role of neural species sensitivity and face sensitivity in visuo-social processing are largely unknown. Conspecific-preference in social perception is evident for multiple sensory modalities and in many species. There is also a dedicated neural network for face processing in primates. However, the evolutionary origin and the relative role of neural species sensitivity and face sensitivity in visuo-social processing are largely unknown. In this comparative study, species sensitivity and face sensitivity to identical visual stimuli (videos of human and dog faces and occiputs) were examined using functional magnetic resonance imaging in dogs (n = 20; 45% female) and humans (n = 30; 50% female). In dogs, the bilateral mid suprasylvian gyrus showed conspecific-preference, no regions exhibited face-preference, and the majority of the visually-responsive cortex showed greater conspecific-preference than face-preference. In humans, conspecific-preferring regions (the right amygdala/hippocampus and the posterior superior temporal sulcus) also showed face-preference, and much of the visually-responsive cortex showed greater face-preference than conspecific-preference. Multivariate pattern analyses (MVPAs) identified species-sensitive regions in both species, but face-sensitive regions only in humans. Across-species representational similarity analyses (RSAs) revealed stronger correspondence between dog and human response patterns for distinguishing conspecific from heterospecific faces than other contrasts. Results unveil functional analogies in dog and human visuo-social processing of conspecificity but suggest that cortical specialization for face perception may not be ubiquitous across mammals. SIGNIFICANCE STATEMENT To explore the evolutionary origins of human face-preference and its relationship to conspecific-preference, we conducted the first comparative and noninvasive visual neuroimaging study of a non-primate and a primate species, dogs and humans. Conspecific-preferring brain regions were observed in both species, but face-preferring brain regions were observed only in humans. In dogs, an overwhelming majority of visually-responsive cortex exhibited greater conspecific-preference than face-preference, whereas in humans, much of the visually-responsive cortex showed greater face-preference than conspecific-preference. Together, these findings unveil functional analogies and differences in the organizing principles of visuo-social processing across two phylogenetically distant mammal species.
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46
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Katajamaa R, Jensen P. Selection for reduced fear in red junglefowl changes brain composition and affects fear memory. ROYAL SOCIETY OPEN SCIENCE 2020; 7:200628. [PMID: 32968523 PMCID: PMC7481730 DOI: 10.1098/rsos.200628] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 08/05/2020] [Indexed: 05/15/2023]
Abstract
Brain size reduction is a common trait in domesticated species when compared to wild conspecifics. This reduction can happen through changes in individual brain regions as a response to selection on specific behaviours. We selected red junglefowl for 10 generations for diverging levels of fear towards humans and measured brain size and composition as well as habituation learning and conditioned place preference learning in young chicks. Brain size relative to body size as well as brainstem region size relative to whole brain size were significantly smaller in chicks selected for low fear of humans compared to chicks selected for high fear of humans. However, when including allometric effects in the model, these differences disappear but a tendency towards larger cerebra in low-fear chickens remains. Low-fear line chicks habituated more effectively to a fearful stimulus with prior experience of that same stimulus, whereas high-fear line chicks with previous experience of the stimulus had a response similar to naive chicks. The phenotypical changes are in line with previously described effects of domestication.
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Affiliation(s)
| | - Per Jensen
- Author for correspondence: Per Jensen e-mail:
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47
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Grewal JS, Gloe T, Hegedus J, Bitterman K, Billings BK, Chengetanai S, Bentil S, Wang VX, Ng JC, Tang CY, Geletta S, Wicinski B, Bertelson M, Tendler BC, Mars RB, Aguirre GK, Rusbridge C, Hof PR, Sherwood CC, Manger PR, Spocter MA. Brain gyrification in wild and domestic canids: Has domestication changed the gyrification index in domestic dogs? J Comp Neurol 2020; 528:3209-3228. [PMID: 32592407 DOI: 10.1002/cne.24972] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 01/09/2023]
Abstract
Over the last 15 years, research on canid cognition has revealed that domestic dogs possess a surprising array of complex sociocognitive skills pointing to the possibility that the domestication process might have uniquely altered their brains; however, we know very little about how evolutionary processes (natural or artificial) might have modified underlying neural structure to support species-specific behaviors. Evaluating the degree of cortical folding (i.e., gyrification) within canids may prove useful, as this parameter is linked to functional variation of the cerebral cortex. Using quantitative magnetic resonance imaging to investigate the impact of domestication on the canine cortical surface, we compared the gyrification index (GI) in 19 carnivore species, including six wild canid and 13 domestic dog individuals. We also explored correlations between global and local GI with brain mass, cortical thickness, white and gray matter volume and surface area. Our results indicated that GI values for domestic dogs are largely consistent with what would be expected for a canid of their given brain mass, although more variable than that observed in wild canids. We also found that GI in canids is positively correlated with cortical surface area, cortical thickness and total cortical gray matter volumes. While we found no evidence of global differences in GI between domestic and wild canids, certain regional differences in gyrification were observed.
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Affiliation(s)
- Jagmeet S Grewal
- Department of Anatomy, Des Moines University, Des Moines, Iowa, USA
| | - Tyler Gloe
- Department of Anatomy, Des Moines University, Des Moines, Iowa, USA
| | - Joseph Hegedus
- Department of Anatomy, Des Moines University, Des Moines, Iowa, USA
| | | | - Brendon K Billings
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Samson Chengetanai
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Sarah Bentil
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa, USA
| | - Victoria X Wang
- Departments of Radiology and Psychiatry,and BioMedical and Engineering Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Johnny C Ng
- Departments of Radiology and Psychiatry,and BioMedical and Engineering Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Cheuk Y Tang
- Departments of Radiology and Psychiatry,and BioMedical and Engineering Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Simon Geletta
- Department of Public Health, Des Moines University, Des Moines, Iowa, USA
| | - Bridget Wicinski
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Mads Bertelson
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Fredericksberg, Denmark
| | - Benjamin C Tendler
- Wellcome Centre for Intergrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Rogier B Mars
- Wellcome Centre for Intergrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.,Donders Institute for Brain, Cognition and Behavior, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Geoffrey K Aguirre
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, Philadelphia, Pennsylvania, USA
| | - Clare Rusbridge
- Fitzpatrick Referrals Orthopedics and Neurology, Fitzpatrick Referrals Ltd, Godalming, UK.,School of Veterinary Medicine, University of Surrey, Guildford, Surrey, UK
| | - Patrick R Hof
- Nash Family Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,New York Consortium in Evolutionary Primatology, New York, New York, USA
| | - Chet C Sherwood
- Department of Anthropology and Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, District of Columbia, USA
| | - Paul R Manger
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Muhammad A Spocter
- Department of Anatomy, Des Moines University, Des Moines, Iowa, USA.,School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa.,College of Veterinary Medicine, Department of Biomedical Sciences, Iowa State University, Ames, Iowa, USA
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48
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Swain CE, Cherubini GB, Mantis P. Low Field MRI Measurements of the Normal Canine Trigeminal Nerve. Front Vet Sci 2020; 7:274. [PMID: 32509809 PMCID: PMC7249853 DOI: 10.3389/fvets.2020.00274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 04/23/2020] [Indexed: 11/13/2022] Open
Abstract
There is no available measuring protocol and reference range for the normal canine trigeminal nerve. This can be problematic in cases of suspected bilateral trigeminal neuropathy since contralateral nerves cannot be a usefully compared. Trigeminal nerves and brain measurements were retrospectively assessed via multiplanar reconstruction (MPR) of 3DT1 post-contrast MR sequences from 137 dogs with no signs or diagnosis of trigeminal disease. Direct measurements of vertical brain height (BH), trigeminal nerves transverse height (TTH) and trigeminal nerves width in dorsal reconstruction (TDW) were made in a plane immediately caudal to the foramen ovale and used to derive trigeminal nerve-to-brain (NB) ratios, including height-to-brain ratio (HBR) and width-to-brain ratio (WBR). HBR (0.09, IQR = 0.08-0.09) and WBR (0.10, IQR = 0.09-0.11) maintained more consistent values across the study population compared to direct measurements of TTH (3.72, IQR = 3.42-4.07) and TDW (4.35 +/− 0.63). Calculated normal reference intervals for HBR and WBR were 0.07-0.11 and 0.08-0.13, respectively and the largest NB ratios recorded in normal dogs were 0.13 and 0.14 for HBR and WBR, respectively. All measurements varied proportionally with weight, including HBR (r = 0.41, p < 0.0001) and small dogs had a significantly smaller HBRs compared to medium (p = 0.0294), large (p < 0.0049) and giant dogs (p < 0.0044). Median HBR was the same across skull types (0.09), however post-hoc analysis detected significantly smaller HBRs in brachycephalic compared to mesaticephalic dogs (p = 0.0494). In conclusion, trigeminal NB ratios may allow for accurate, objective assessment of the canine trigeminal nerves on MRI but further quantification of the effects of weight and skull type on suggested reference intervals is needed.
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49
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Aulet LS, Chiu VC, Prichard A, Spivak M, Lourenco SF, Berns GS. Canine sense of quantity: evidence for numerical ratio-dependent activation in parietotemporal cortex. Biol Lett 2019; 15:20190666. [PMID: 31847744 PMCID: PMC6936025 DOI: 10.1098/rsbl.2019.0666] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The approximate number system (ANS), which supports the rapid estimation of quantity, emerges early in human development and is widespread across species. Neural evidence from both human and non-human primates suggests the parietal cortex as a primary locus of numerical estimation, but it is unclear whether the numerical competencies observed across non-primate species are subserved by similar neural mechanisms. Moreover, because studies with non-human animals typically involve extensive training, little is known about the spontaneous numerical capacities of non-human animals. To address these questions, we examined the neural underpinnings of number perception using awake canine functional magnetic resonance imaging. Dogs passively viewed dot arrays that varied in ratio and, critically, received no task-relevant training or exposure prior to testing. We found evidence of ratio-dependent activation, which is a key feature of the ANS, in canine parietotemporal cortex in the majority of dogs tested. This finding is suggestive of a neural mechanism for quantity perception that has been conserved across mammalian evolution.
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Affiliation(s)
- Lauren S Aulet
- Department of Psychology, Emory University, Atlanta, GA 30322, USA
| | - Veronica C Chiu
- Department of Psychology, Emory University, Atlanta, GA 30322, USA
| | - Ashley Prichard
- Department of Psychology, Emory University, Atlanta, GA 30322, USA
| | - Mark Spivak
- Comprehensive Pet Therapy, Atlanta, GA 30328, USA
| | | | - Gregory S Berns
- Department of Psychology, Emory University, Atlanta, GA 30322, USA
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50
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Gallup AC, Moscatello L, Massen JJM. Brain weight predicts yawn duration across domesticated dog breeds. Curr Zool 2019; 66:401-405. [PMID: 32617088 PMCID: PMC7319467 DOI: 10.1093/cz/zoz060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Accepted: 11/24/2019] [Indexed: 12/13/2022] Open
Abstract
Previous research shows that yawning enhances intracranial circulation and regulates brain temperature. Consistent with these functional outcomes, yawn duration correlates positively with interspecies variation in brain weight across mammals, with robust relationships documented at both the taxonomic rank of class and the more restricted scale of family (e.g., Felidae). This study provides the first investigation into whether differences in brain weight within a single species, domesticated dogs Canis lupus familiaris, can predict intraspecific variation in yawn duration. Measures of yawn duration were obtained from public videos available online and then paired with previously published brain and body weight data of different dog breeds. The final sample consisted of 272 yawns from 198 dogs across 23 breeds. Consistent with recent studies, we find robust correlations between yawn duration and brain weight across breeds. Moreover, these correlations remain significant after controlling for differences in body weight across breeds. These findings replicate and extend upon past work in this area and provide further support that yawns evolved to serve an important and large-scale neurophysiologic function.
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Affiliation(s)
- Andrew C Gallup
- Psychology Program, Department of Social and Behavioral Sciences, SUNY Polytechnic Institute, Utica, NY, 13502, USA
| | - Lea Moscatello
- Department of Psychology, SUNY College at Oneonta, Oneonta, NY, 13820, USA
| | - Jorg J M Massen
- Animal Ecology Group, Department of Biology, Utrecht University, Padualaan 8, Utrecht, CH, 3584, The Netherlands
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