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Veale R, Takahashi M. Pathways for Naturalistic Looking Behavior in Primate II. Superior Colliculus Integrates Parallel Top-down and Bottom-up Inputs. Neuroscience 2024; 545:86-110. [PMID: 38484836 DOI: 10.1016/j.neuroscience.2024.03.001] [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: 07/01/2023] [Revised: 02/15/2024] [Accepted: 03/01/2024] [Indexed: 03/24/2024]
Abstract
Volitional signals for gaze control are provided by multiple parallel pathways converging on the midbrain superior colliculus (SC), whose deeper layers output to the brainstem gaze circuits. In the first of two papers (Takahashi and Veale, 2023), we described the properties of gaze behavior of several species under both laboratory and natural conditions, as well as the current understanding of the brainstem and spinal cord circuits implementing gaze control in primate. In this paper, we review the parallel pathways by which sensory and task information reaches SC and how these sensory and task signals interact within SC's multilayered structure. This includes both bottom-up (world statistics) signals mediated by sensory cortex, association cortex, and subcortical structures, as well as top-down (goal and task) influences which arrive via either direct excitatory pathways from cerebral cortex, or via indirect basal ganglia relays resulting in inhibition or dis-inhibition as appropriate for alternative behaviors. Models of attention such as saliency maps serve as convenient frameworks to organize our understanding of both the separate computations of each neural pathway, as well as the interaction between the multiple parallel pathways influencing gaze. While the spatial interactions between gaze's neural pathways are relatively well understood, the temporal interactions between and within pathways will be an important area of future study, requiring both improved technical methods for measurement and improvement of our understanding of how temporal dynamics results in the observed spatiotemporal allocation of gaze.
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Affiliation(s)
- Richard Veale
- Department of Neurobiology, Graduate School of Medicine, Kyoto University, Japan
| | - Mayu Takahashi
- Department of Systems Neurophysiology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan.
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2
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Kearney BE, Terpou BA, Densmore M, Shaw SB, Théberge J, Jetly R, McKinnon MC, Lanius RA. How the body remembers: Examining the default mode and sensorimotor networks during moral injury autobiographical memory retrieval in PTSD. Neuroimage Clin 2023; 38:103426. [PMID: 37207593 PMCID: PMC10206209 DOI: 10.1016/j.nicl.2023.103426] [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: 02/13/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/21/2023]
Abstract
Neural representations of sensory percepts and motor responses constitute key elements of autobiographical memory. However, these representations may remain as unintegrated sensory and motor fragments in traumatic memory, thus contributing toward re-experiencing and reliving symptoms in trauma-related conditions such as post-traumatic stress disorder (PTSD). Here, we investigated the sensorimotor network (SMN) and posterior default mode network (pDMN) using a group independent component analysis (ICA) by examining their functional connectivity during a script-driven memory retrieval paradigm of (potentially) morally injurious events in individuals with PTSD and healthy controls. Moral injury (MI), where an individual acts or fails to act in a morally aligned manner, is examined given its inherent ties to disrupted motor planning and thus sensorimotor mechanisms. Our findings revealed significant differences in functional network connectivity across the SMN and pDMN during MI retrieval in participants with PTSD (n = 65) as compared to healthy controls (n = 25). No such significant group-wise differences emerged during retrieval of a neutral memory. PTSD-related alterations included hyperconnectivity between the SMN and pDMN, enhanced within-network connectivity of the SMN with premotor areas, and increased recruitment of the supramarginal gyrus into both the SMN and the pDMN during MI retrieval. In parallel with these neuroimaging findings, a positive correlation was found between PTSD severity and subjective re-experiencing intensity ratings after MI retrieval. These results suggest a neural basis for traumatic re-experiencing, where reliving and/or re-enacting a past morally injurious event in the form of sensory and motor fragments occurs in place of retrieving a complete, past-contextualized narrative as put forth by Brewin and colleagues (1996) and Conway and Pleydell-Pearce (2000). These findings have implications for bottom-up treatments targeting directly the sensory and motoric elements of traumatic experiences.
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Affiliation(s)
- Breanne E Kearney
- Department of Neuroscience, Western University, London, Ontario, Canada
| | - Braeden A Terpou
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada
| | - Maria Densmore
- Department of Psychiatry, Western University, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada
| | - Saurabh B Shaw
- Department of Psychiatry, Western University, London, Ontario, Canada
| | - Jean Théberge
- Department of Psychiatry, Western University, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada; Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Rakesh Jetly
- Institute of Mental Health Research, University of Ottawa, Ottawa, Ontario, Canada
| | - Margaret C McKinnon
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada; Mood Disorders Program, St. Joseph's Healthcare, Hamilton, Ontario, Canada; Homewood Research Institute, Guelph, Ontario, Canada
| | - Ruth A Lanius
- Department of Neuroscience, Western University, London, Ontario, Canada; Department of Psychiatry, Western University, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada; Homewood Research Institute, Guelph, Ontario, Canada.
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3
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Shine JM. Adaptively navigating affordance landscapes: How interactions between the superior colliculus and thalamus coordinate complex, adaptive behaviour. Neurosci Biobehav Rev 2022; 143:104921. [DOI: 10.1016/j.neubiorev.2022.104921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 09/08/2022] [Accepted: 09/08/2022] [Indexed: 11/06/2022]
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Awathale SN, Waghade AM, Kawade HM, Jadhav G, Choudhary AG, Sagarkar S, Sakharkar AJ, Subhedar NK, Kokare DM. Neuroplastic Changes in the Superior Colliculus and Hippocampus in Self-rewarding Paradigm: Importance of Visual Cues. Mol Neurobiol 2021; 59:890-915. [PMID: 34797522 DOI: 10.1007/s12035-021-02597-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 10/11/2021] [Indexed: 12/21/2022]
Abstract
Coincident excitation via different sensory modalities encoding objects of positive salience is known to facilitate learning and memory. With a view to dissect the contribution of visual cues in inducing adaptive neural changes, we monitored the lever press activity of a rat conditioned to self-administer sweet food pellets in the presence/absence of light cues. Application of light cues facilitated learning and consolidation of long-term memory. The superior colliculus (SC) of rats trained on light cue showed increased neuronal activity, dendritic branching, and brain-derived neurotrophic factor (BDNF) protein and mRNA expression. Concomitantly, the hippocampus showed augmented neurogenesis as well as BDNF protein and mRNA expression. While intra-SC administration of U0126 (inhibitor of ERK 1/2 and long-term memory) impaired memory formation, lidocaine (local anaesthetic) hindered memory recall. The light cue-dependent sweet food pellet self-administration was coupled with increased efflux of dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in the nucleus accumbens shell (AcbSh). In conditioned rats, pharmacological inhibition of glutamatergic signalling in dentate gyrus (DG) reduced lever press activity, as well as DA and DOPAC secretion in the AcbSh. We suggest that the neuroplastic changes in the SC and hippocampus might represent memory engrams sculpted by visual cues encoding reward information.
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Affiliation(s)
- Sanjay N Awathale
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440 033, India
| | - Akash M Waghade
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440 033, India
| | - Harish M Kawade
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440 033, India
| | - Gouri Jadhav
- Department of Biotechnology, Savitribai Phule Pune University, Pune, 411 007, India
| | - Amit G Choudhary
- Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pune, 411 008, India
| | - Sneha Sagarkar
- Department of Zoology, Savitribai Phule Pune University, Pune, 411 007, India
| | - Amul J Sakharkar
- Department of Biotechnology, Savitribai Phule Pune University, Pune, 411 007, India
| | - Nishikant K Subhedar
- Indian Institute of Science Education and Research (IISER), Dr. Homi Bhabha Road, Pune, 411 008, India
| | - Dadasaheb M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440 033, India.
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Rezaul Karim AKM, Proulx MJ, de Sousa AA, Likova LT. Neuroplasticity and Crossmodal Connectivity in the Normal, Healthy Brain. PSYCHOLOGY & NEUROSCIENCE 2021; 14:298-334. [PMID: 36937077 PMCID: PMC10019101 DOI: 10.1037/pne0000258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Objective Neuroplasticity enables the brain to establish new crossmodal connections or reorganize old connections which are essential to perceiving a multisensorial world. The intent of this review is to identify and summarize the current developments in neuroplasticity and crossmodal connectivity, and deepen understanding of how crossmodal connectivity develops in the normal, healthy brain, highlighting novel perspectives about the principles that guide this connectivity. Methods To the above end, a narrative review is carried out. The data documented in prior relevant studies in neuroscience, psychology and other related fields available in a wide range of prominent electronic databases are critically assessed, synthesized, interpreted with qualitative rather than quantitative elements, and linked together to form new propositions and hypotheses about neuroplasticity and crossmodal connectivity. Results Three major themes are identified. First, it appears that neuroplasticity operates by following eight fundamental principles and crossmodal integration operates by following three principles. Second, two different forms of crossmodal connectivity, namely direct crossmodal connectivity and indirect crossmodal connectivity, are suggested to operate in both unisensory and multisensory perception. Third, three principles possibly guide the development of crossmodal connectivity into adulthood. These are labeled as the principle of innate crossmodality, the principle of evolution-driven 'neuromodular' reorganization and the principle of multimodal experience. These principles are combined to develop a three-factor interaction model of crossmodal connectivity. Conclusions The hypothesized principles and the proposed model together advance understanding of neuroplasticity, the nature of crossmodal connectivity, and how such connectivity develops in the normal, healthy brain.
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Xie Z, Wang M, Liu Z, Shang C, Zhang C, Sun L, Gu H, Ran G, Pei Q, Ma Q, Huang M, Zhang J, Lin R, Zhou Y, Zhang J, Zhao M, Luo M, Wu Q, Cao P, Wang X. Transcriptomic encoding of sensorimotor transformation in the midbrain. eLife 2021; 10:e69825. [PMID: 34318750 PMCID: PMC8341986 DOI: 10.7554/elife.69825] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/25/2021] [Indexed: 12/31/2022] Open
Abstract
Sensorimotor transformation, a process that converts sensory stimuli into motor actions, is critical for the brain to initiate behaviors. Although the circuitry involved in sensorimotor transformation has been well delineated, the molecular logic behind this process remains poorly understood. Here, we performed high-throughput and circuit-specific single-cell transcriptomic analyses of neurons in the superior colliculus (SC), a midbrain structure implicated in early sensorimotor transformation. We found that SC neurons in distinct laminae expressed discrete marker genes. Of particular interest, Cbln2 and Pitx2 were key markers that define glutamatergic projection neurons in the optic nerve (Op) and intermediate gray (InG) layers, respectively. The Cbln2+ neurons responded to visual stimuli mimicking cruising predators, while the Pitx2+ neurons encoded prey-derived vibrissal tactile cues. By forming distinct input and output connections with other brain areas, these neuronal subtypes independently mediated behaviors of predator avoidance and prey capture. Our results reveal that, in the midbrain, sensorimotor transformation for different behaviors may be performed by separate circuit modules that are molecularly defined by distinct transcriptomic codes.
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Affiliation(s)
- Zhiyong Xie
- National Institute of Biological SciencesBeijingChina
| | - Mengdi Wang
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Zeyuan Liu
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Congping Shang
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory)GuangzhouChina
| | - Changjiang Zhang
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Le Sun
- Beijing Institute for Brain Disorders, Capital Medical UniversityBeijingChina
| | - Huating Gu
- National Institute of Biological SciencesBeijingChina
| | - Gengxin Ran
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Qing Pei
- National Institute of Biological SciencesBeijingChina
| | - Qiang Ma
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
| | - Meizhu Huang
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory)GuangzhouChina
| | - Junjing Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal UniversityBeijingChina
| | - Rui Lin
- National Institute of Biological SciencesBeijingChina
| | - Youtong Zhou
- National Institute of Biological SciencesBeijingChina
| | - Jiyao Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal UniversityBeijingChina
| | - Miao Zhao
- National Institute of Biological SciencesBeijingChina
| | - Minmin Luo
- National Institute of Biological SciencesBeijingChina
- Chinese Institute for Brain ResearchBeijingChina
| | - Qian Wu
- State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal UniversityBeijingChina
| | - Peng Cao
- National Institute of Biological SciencesBeijingChina
- Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua UniversityBeijingChina
| | - Xiaoqun Wang
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of SciencesBeijingChina
- University of Chinese Academy of SciencesBeijingChina
- Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory)GuangzhouChina
- Beijing Institute for Brain Disorders, Capital Medical UniversityBeijingChina
- Chinese Institute for Brain ResearchBeijingChina
- Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University & Capital Medical UniversityBeijingChina
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7
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Sajad A, Sadeh M, Crawford JD. Spatiotemporal transformations for gaze control. Physiol Rep 2020; 8:e14533. [PMID: 32812395 PMCID: PMC7435051 DOI: 10.14814/phy2.14533] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 12/13/2022] Open
Abstract
Sensorimotor transformations require spatiotemporal coordination of signals, that is, through both time and space. For example, the gaze control system employs signals that are time-locked to various sensorimotor events, but the spatial content of these signals is difficult to assess during ordinary gaze shifts. In this review, we describe the various models and methods that have been devised to test this question, and their limitations. We then describe a new method that can (a) simultaneously test between all of these models during natural, head-unrestrained conditions, and (b) track the evolving spatial continuum from target (T) to future gaze coding (G, including errors) through time. We then summarize some applications of this technique, comparing spatiotemporal coding in the primate frontal eye field (FEF) and superior colliculus (SC). The results confirm that these areas preferentially encode eye-centered, effector-independent parameters, and show-for the first time in ordinary gaze shifts-a spatial transformation between visual and motor responses from T to G coding. We introduce a new set of spatial models (T-G continuum) that revealed task-dependent timing of this transformation: progressive during a memory delay between vision and action, and almost immediate without such a delay. We synthesize the results from our studies and supplement it with previous knowledge of anatomy and physiology to propose a conceptual model where cumulative transformation noise is realized as inaccuracies in gaze behavior. We conclude that the spatiotemporal transformation for gaze is both local (observed within and across neurons in a given area) and distributed (with common signals shared across remote but interconnected structures).
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Affiliation(s)
- Amirsaman Sajad
- Centre for Vision ResearchYork UniversityTorontoONCanada
- Psychology DepartmentVanderbilt UniversityNashvilleTNUSA
| | - Morteza Sadeh
- Centre for Vision ResearchYork UniversityTorontoONCanada
- Department of NeurosurgeryUniversity of Illinois at ChicagoChicagoILUSA
| | - John Douglas Crawford
- Centre for Vision ResearchYork UniversityTorontoONCanada
- Vision: Science to Applications Program (VISTA)Neuroscience Graduate Diploma ProgramDepartments of Psychology, Biology, Kinesiology & Health SciencesYork UniversityTorontoONCanada
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8
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The influence of subcortical shortcuts on disordered sensory and cognitive processing. Nat Rev Neurosci 2020; 21:264-276. [PMID: 32269315 DOI: 10.1038/s41583-020-0287-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2020] [Indexed: 12/14/2022]
Abstract
The very earliest stages of sensory processing have the potential to alter how we perceive and respond to our environment. These initial processing circuits can incorporate subcortical regions, such as the thalamus and brainstem nuclei, which mediate complex interactions with the brain's cortical processing hierarchy. These subcortical pathways, many of which we share with other animals, are not merely vestigial but appear to function as 'shortcuts' that ensure processing efficiency and preservation of vital life-preserving functions, such as harm avoidance, adaptive social interactions and efficient decision-making. Here, we propose that functional interactions between these higher-order and lower-order brain areas contribute to atypical sensory and cognitive processing that characterizes numerous neuropsychiatric disorders.
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9
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Hoy JL, Bishop HI, Niell CM. Defined Cell Types in Superior Colliculus Make Distinct Contributions to Prey Capture Behavior in the Mouse. Curr Biol 2019; 29:4130-4138.e5. [PMID: 31761701 DOI: 10.1016/j.cub.2019.10.017] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 08/28/2019] [Accepted: 10/10/2019] [Indexed: 02/06/2023]
Abstract
The superior colliculus (SC) plays a highly conserved role in visual processing and mediates visual orienting behaviors across species, including both overt motor orienting [1, 2] and orienting of attention [3, 4]. To determine the specific circuits within the superficial superior colliculus (sSC) that drive orienting and approach behavior toward appetitive stimuli, we explored the role of three genetically defined cell types in mediating prey capture in mice. Chemogenetic inactivation of two classically defined cell types, the wide-field (WF) and narrow-field (NF) vertical neurons, revealed that they are involved in distinct aspects of prey capture. WF neurons were required for rapid prey detection and distant approach initiation, whereas NF neurons were required for accurate orienting during pursuit as well as approach initiation and continuity. In contrast, prey capture did not require parvalbumin-expressing (PV) neurons that have previously been implicated in fear responses. The visual coding and projection targets of WF and NF cells were consistent with their roles in prey detection versus pursuit, respectively. Thus, our studies link specific neural circuit connectivity and function with stimulus detection and orienting behavior, providing insight into visuomotor and attentional mechanisms mediated by superior colliculus.
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Affiliation(s)
- Jennifer L Hoy
- Department of Biology, University of Nevada, Reno, Reno, NV 89557, USA.
| | - Hannah I Bishop
- Department of Biology and Institute of Neuroscience, University of Oregon, Eugene, OR 97403, USA
| | - Cristopher M Niell
- Department of Biology and Institute of Neuroscience, University of Oregon, Eugene, OR 97403, USA.
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10
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Brooks JX, Cullen KE. Predictive Sensing: The Role of Motor Signals in Sensory Processing. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2019; 4:842-850. [PMID: 31401034 DOI: 10.1016/j.bpsc.2019.06.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 06/06/2019] [Accepted: 06/07/2019] [Indexed: 12/12/2022]
Abstract
The strategy of integrating motor signals with sensory information during voluntary behavior is a general feature of sensory processing. It is required to distinguish externally applied (exafferent) from self-generated (reafferent) sensory inputs. This distinction, in turn, underlies our ability to achieve both perceptual stability and accurate motor control during everyday activities. In this review, we consider the results of recent experiments that have provided circuit-level insight into how motor-related inputs to sensory areas selectively cancel self-generated sensory inputs during active behaviors. These studies have revealed both common strategies and important differences across systems. Sensory reafference is suppressed at the earliest stages of central processing in the somatosensory, vestibular, and auditory systems, with the cerebellum and cerebellum-like structures playing key roles. Furthermore, motor-related inputs can also suppress reafferent responses at higher levels of processing such as the cortex-a strategy preferentially used in visual processing. These recent findings have important implications for understanding how the brain achieves the flexibility required to continuously calibrate relationships between motor signals and the resultant sensory feedback, a computation necessary for our subjective awareness that we control both our actions and their sensory consequences.
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Affiliation(s)
- Jessica X Brooks
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - Kathleen E Cullen
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.
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11
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Hoffmann S, Vega-Zuniga T, Greiter W, Krabichler Q, Bley A, Matthes M, Zimmer C, Firzlaff U, Luksch H. Congruent representation of visual and acoustic space in the superior colliculus of the echolocating bat Phyllostomus discolor. Eur J Neurosci 2016; 44:2685-2697. [PMID: 27600873 DOI: 10.1111/ejn.13394] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 08/29/2016] [Accepted: 08/31/2016] [Indexed: 11/29/2022]
Abstract
The midbrain superior colliculus (SC) commonly features a retinotopic representation of visual space in its superficial layers, which is congruent with maps formed by multisensory neurons and motor neurons in its deep layers. Information flow between layers is suggested to enable the SC to mediate goal-directed orienting movements. While most mammals strongly rely on vision for orienting, some species such as echolocating bats have developed alternative strategies, which raises the question how sensory maps are organized in these animals. We probed the visual system of the echolocating bat Phyllostomus discolor and found that binocular high acuity vision is frontally oriented and thus aligned with the biosonar system, whereas monocular visual fields cover a large area of peripheral space. For the first time in echolocating bats, we could show that in contrast with other mammals, visual processing is restricted to the superficial layers of the SC. The topographic representation of visual space, however, followed the general mammalian pattern. In addition, we found a clear topographic representation of sound azimuth in the deeper collicular layers, which was congruent with the superficial visual space map and with a previously documented map of orienting movements. Especially for bats navigating at high speed in densely structured environments, it is vitally important to transfer and coordinate spatial information between sensors and motor systems. Here, we demonstrate first evidence for the existence of congruent maps of sensory space in the bat SC that might serve to generate a unified representation of the environment to guide motor actions.
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Affiliation(s)
- Susanne Hoffmann
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany.
| | - Tomas Vega-Zuniga
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Wolfgang Greiter
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Quirin Krabichler
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Alexandra Bley
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Mariana Matthes
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Christiane Zimmer
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Uwe Firzlaff
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
| | - Harald Luksch
- Technische Universität München, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
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12
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Abstract
The "problem of serial order in behavior," as formulated and discussed by Lashley (1951), is arguably more pervasive and more profound both than originally stated and than currently appreciated. We spell out two complementary aspects of what we term the generalized problem of behavior: (i) multimodality, stemming from the disparate nature of the sensorimotor variables and processes that underlie behavior, and (ii) concurrency, which reflects the parallel unfolding in time of these processes and of their asynchronous interactions. We illustrate these on a number of examples, with a special focus on language, briefly survey the computational approaches to multimodal concurrency, offer some hypotheses regarding the manner in which brains address it, and discuss some of the broader implications of these as yet unresolved issues for cognitive science.
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Affiliation(s)
- Oren Kolodny
- Department of Zoology, Tel Aviv University, Tel Aviv, Israel
| | - Shimon Edelman
- Department of Psychology, Cornell University, Ithaca, NY, USA.
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13
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Processing of visually evoked innate fear by a non-canonical thalamic pathway. Nat Commun 2015; 6:6756. [PMID: 25854147 PMCID: PMC4403372 DOI: 10.1038/ncomms7756] [Citation(s) in RCA: 199] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 02/24/2015] [Indexed: 12/28/2022] Open
Abstract
The ability of animals to respond to life-threatening stimuli is essential for survival. Although vision provides one of the major sensory inputs for detecting threats across animal species, the circuitry underlying defensive responses to visual stimuli remains poorly defined. Here, we investigate the circuitry underlying innate defensive behaviours elicited by predator-like visual stimuli in mice. Our results demonstrate that neurons in the superior colliculus (SC) are essential for a variety of acute and persistent defensive responses to overhead looming stimuli. Optogenetic mapping revealed that SC projections to the lateral posterior nucleus (LP) of the thalamus, a non-canonical polymodal sensory relay, are sufficient to mimic visually evoked fear responses. In vivo electrophysiology experiments identified a di-synaptic circuit from SC through LP to the lateral amygdale (Amg), and lesions of the Amg blocked the full range of visually evoked defensive responses. Our results reveal a novel collicular-thalamic-Amg circuit important for innate defensive responses to visual threats.
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14
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Ngan NH, Matsumoto J, Takamura Y, Tran AH, Ono T, Nishijo H. Neuronal correlates of attention and its disengagement in the superior colliculus of rat. Front Integr Neurosci 2015; 9:9. [PMID: 25741252 PMCID: PMC4332380 DOI: 10.3389/fnint.2015.00009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 01/27/2015] [Indexed: 01/07/2023] Open
Abstract
Orienting attention to a new target requires prior disengagement of attention from the current focus. Previous studies indicate that the superior colliculus (SC) plays an important role in attention. However, recordings of responses of SC neurons during attentional disengagement have not yet been reported. Here, we analyzed rat SC neuronal activity during performance of an attention-shift task with and without disengagement. In this task, conditioned stimuli (CSs; right and/or left light-flash or sound) were sequentially presented. To obtain an intracranial self-stimulation reward, rats were required to lick a spout when an infrequent conditioned stimulus appeared (reward trials). In the disengagement reward trials, configural stimuli consisting of an infrequent stimulus and frequent stimulus in the former trials were presented; in the non-disengagement reward trials, only an infrequent stimulus was presented. Of the 186 SC neurons responding to the CSs, 41 showed stronger responses to the CSs in the disengagement reward trials than in the non-disengagement reward trials (disengagement-related neurons). Furthermore, lick latencies in the disengagement reward trials were negatively correlated with response magnitudes to the CSs in half of the disengagement-related neurons. These disengagement-related neurons were located mainly in the deep layers of the SC. Another 70 SC neurons responded to the CSs in both disengagement and non-disengagement reward trials, suggesting that these neurons were involved in attention engagement. Our results suggest complementary mechanisms of attentional shift based on two subpopulations of neurons in the SC.
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Affiliation(s)
- Nguyen H Ngan
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Yusaku Takamura
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Anh H Tran
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Taketoshi Ono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
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Whole-body prepulse inhibition protocol to test sensorymotor gating mechanisms in monkeys. PLoS One 2014; 9:e105551. [PMID: 25144368 PMCID: PMC4140807 DOI: 10.1371/journal.pone.0105551] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 07/23/2014] [Indexed: 11/25/2022] Open
Abstract
Prepulse inhibition (PPI) is the decrease of startle reflex amplitude when a slight stimulus is previously generated. This paradigm may provide valuable information about sensorimotor gating functionality. Here we aimed at determining the inhibited and uninhibited startle response of capuchin monkeys (Sapajus spp.), and to evaluate the role of the superior colliculus in PPI. Capuchin monkeys were tested in a whole-body protocol, to determine the best startle amplitude and interstimuli interval. Additionally we tested two subjects with bilateral superior colliculus damage in this protocol. Results show that 115 dB auditory pulse has induced the best startle response. In contrast to reports in other species, no habituation to the auditory stimuli was observed here in capuchins. Also, startle reflex inhibition was optimal after 120 msec interstimuli interval. Finally, there was a downward tendency of percentage inhibition in superior colliculus-lesioned monkeys. Our data provides the possibility of further studies with whole-body protocol in capuchin monkeys and reinforces the importance of the superior colliculus in PPI.
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Nguyen MN, Matsumoto J, Hori E, Maior RS, Tomaz C, Tran AH, Ono T, Nishijo H. Neuronal responses to face-like and facial stimuli in the monkey superior colliculus. Front Behav Neurosci 2014; 8:85. [PMID: 24672448 PMCID: PMC3955777 DOI: 10.3389/fnbeh.2014.00085] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 02/27/2014] [Indexed: 11/30/2022] Open
Abstract
The superficial layers of the superior colliculus (sSC) appear to function as a subcortical visual pathway that bypasses the striate cortex for the rapid processing of coarse facial information. We investigated the responses of neurons in the monkey sSC during a delayed non-matching-to-sample (DNMS) task in which monkeys were required to discriminate among five categories of visual stimuli [photos of faces with different gaze directions, line drawings of faces, face-like patterns (three dark blobs on a bright oval), eye-like patterns, and simple geometric patterns]. Of the 605 sSC neurons recorded, 216 neurons responded to the visual stimuli. Among the stimuli, face-like patterns elicited responses with the shortest latencies. Low-pass filtering of the images did not influence the responses. However, scrambling of the images increased the responses in the late phase, and this was consistent with a feedback influence from upstream areas. A multidimensional scaling (MDS) analysis of the population data indicated that the sSC neurons could separately encode face-like patterns during the first 25-ms period after stimulus onset, and stimulus categorization developed in the next three 25-ms periods. The amount of stimulus information conveyed by the sSC neurons and the number of stimulus-differentiating neurons were consistently higher during the 2nd to 4th 25-ms periods than during the first 25-ms period. These results suggested that population activity of the sSC neurons preferentially filtered face-like patterns with short latencies to allow for the rapid processing of coarse facial information and developed categorization of the stimuli in later phases through feedback from upstream areas.
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Affiliation(s)
- Minh Nui Nguyen
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Jumpei Matsumoto
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Etsuro Hori
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Rafael Souto Maior
- Primate Center and Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasília Brasilia, Brazil
| | - Carlos Tomaz
- Primate Center and Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasília Brasilia, Brazil
| | - Anh H Tran
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Taketoshi Ono
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
| | - Hisao Nishijo
- System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama Toyama, Japan
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Corrigan F, Grand D. Brainspotting: Recruiting the midbrain for accessing and healing sensorimotor memories of traumatic activation. Med Hypotheses 2013; 80:759-66. [DOI: 10.1016/j.mehy.2013.03.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 03/08/2013] [Indexed: 01/14/2023]
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18
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Jóhannesson ÓI, Kristjánsson Á. Violating the main sequence: asymmetries in saccadic peak velocities for saccades into the temporal versus nasal hemifields. Exp Brain Res 2013; 227:101-10. [DOI: 10.1007/s00221-013-3490-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 03/14/2013] [Indexed: 11/29/2022]
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Ma R, Cui H, Lee SH, Anastasio TJ, Malpeli JG. Predictive encoding of moving target trajectory by neurons in the parabigeminal nucleus. J Neurophysiol 2013; 109:2029-43. [PMID: 23365185 DOI: 10.1152/jn.01032.2012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Intercepting momentarily invisible moving objects requires internally generated estimations of target trajectory. We demonstrate here that the parabigeminal nucleus (PBN) encodes such estimations, combining sensory representations of target location, extrapolated positions of briefly obscured targets, and eye position information. Cui and Malpeli (Cui H, Malpeli JG. J Neurophysiol 89: 3128-3142, 2003) reported that PBN activity for continuously visible tracked targets is determined by retinotopic target position. Here we show that when cats tracked moving, blinking targets the relationship between activity and target position was similar for ON and OFF phases (400 ms for each phase). The dynamic range of activity evoked by virtual targets was 94% of that of real targets for the first 200 ms after target offset and 64% for the next 200 ms. Activity peaked at about the same best target position for both real and virtual targets. PBN encoding of target position takes into account changes in eye position resulting from saccades, even without visual feedback. Since PBN response fields are retinotopically organized, our results suggest that activity foci associated with real and virtual targets at a given target position lie in the same physical location in the PBN, i.e., a retinotopic as well as a rate encoding of virtual-target position. We also confirm that PBN activity is specific to the intended target of a saccade and is predictive of which target will be chosen if two are offered. A Bayesian predictor-corrector model is presented that conceptually explains the differences in the dynamic ranges of PBN neuronal activity evoked during tracking of real and virtual targets.
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Affiliation(s)
- Rui Ma
- Neuroscience Program, University of Illinois, Urbana, Illinois 61820, USA
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Nguyen MN, Hori E, Matsumoto J, Tran AH, Ono T, Nishijo H. Neuronal responses to face-like stimuli in the monkey pulvinar. Eur J Neurosci 2012; 37:35-51. [DOI: 10.1111/ejn.12020] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 08/27/2012] [Accepted: 09/14/2012] [Indexed: 11/30/2022]
Affiliation(s)
- Minh Nui Nguyen
- System Emotional Science; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Sugitani 2630; Toyama; 930-0194; Japan
| | - Etsuro Hori
- System Emotional Science; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Sugitani 2630; Toyama; 930-0194; Japan
| | - Jumpei Matsumoto
- System Emotional Science; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Sugitani 2630; Toyama; 930-0194; Japan
| | - Anh Hai Tran
- System Emotional Science; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Sugitani 2630; Toyama; 930-0194; Japan
| | - Taketoshi Ono
- System Emotional Science; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Sugitani 2630; Toyama; 930-0194; Japan
| | - Hisao Nishijo
- System Emotional Science; Graduate School of Medicine and Pharmaceutical Sciences; University of Toyama; Sugitani 2630; Toyama; 930-0194; Japan
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21
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Redgrave P, Rodriguez M, Smith Y, Rodriguez-Oroz MC, Lehericy S, Bergman H, Agid Y, DeLong MR, Obeso JA. Goal-directed and habitual control in the basal ganglia: implications for Parkinson's disease. Nat Rev Neurosci 2010; 11:760-72. [PMID: 20944662 PMCID: PMC3124757 DOI: 10.1038/nrn2915] [Citation(s) in RCA: 695] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Progressive loss of the ascending dopaminergic projection in the basal ganglia is a fundamental pathological feature of Parkinson's disease. Studies in animals and humans have identified spatially segregated functional territories in the basal ganglia for the control of goal-directed and habitual actions. In patients with Parkinson's disease the loss of dopamine is predominantly in the posterior putamen, a region of the basal ganglia associated with the control of habitual behaviour. These patients may therefore be forced into a progressive reliance on the goal-directed mode of action control that is mediated by comparatively preserved processing in the rostromedial striatum. Thus, many of their behavioural difficulties may reflect a loss of normal automatic control owing to distorting output signals from habitual control circuits, which impede the expression of goal-directed action.
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Affiliation(s)
- Peter Redgrave
- Neuroscience Research Unit, Department of Psychology, University of Sheffield, UK.
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22
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In vivo retinotopic mapping of superior colliculus using manganese-enhanced magnetic resonance imaging. Neuroimage 2010; 54:389-95. [PMID: 20633657 DOI: 10.1016/j.neuroimage.2010.07.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/27/2010] [Accepted: 07/06/2010] [Indexed: 11/24/2022] Open
Abstract
The superior colliculus (SC) is a dome-shaped subcortical laminar structure in the mammalian midbrain, whose superficial layers receive visual information from the retina in a topological order. Despite the increasing number of studies investigating retinotopic projection in visual brain development and disorders, in vivo, high-resolution 3D mapping of topographic organization in the subcortical visual nuclei has not yet been available. This study explores the capability of 3D manganese-enhanced MRI (MEMRI) at 200 μm isotropic resolution for in vivo retinotopic mapping of the rat SC upon partial transection of the intraorbital optic nerve. One day after intravitreal Mn(2+) injection into both eyes, animals with partial transection at the right superior intraorbital optic nerve in Group 1 (n=8) exhibited a significantly lower T1-weighted signal intensity in the lateral region of the left SC compared to the left medial SC and right control SC. Partial transection toward the temporal or nasal region of the right intraorbital optic nerve in Group 2 (n=7) led to T1-weighted hypointensity in the rostral or caudal region of the left SC, whereas a clear border was observed separating 2 halves of the left SC in all groups. Previous histological and electrophysiological studies showed that the retinal ganglion cell axons emanating from superior, inferior, nasal and temporal retina projected respectively to the contralateral lateral, medial, caudal and rostral SC in rodents. While this topological pattern is preserved in the intraorbital optic nerve, it was shown that partial transection of the superior intraorbital optic nerve led to primary injury predominantly in the superior but not inferior retina and optic nerve. The results of this study demonstrated the sensitivity of submillimeter-resolution MEMRI for in vivo, 3D mapping of the precise retinotopic projections in SC upon reduced anterograde axonal transport of Mn(2+) ions from localized regions of the anterior visual pathways to the subcortical midbrain nuclei. Future MEMRI studies are envisioned that measure the topographic changes in brain development, diseases, plasticity and regeneration therapies in a global and longitudinal setting.
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Aparicio MA, Saldaña E. Tectotectal neurons and projections: a proposal to establish a consistent nomenclature. Anat Rec (Hoboken) 2008; 292:175-7. [PMID: 19089893 DOI: 10.1002/ar.20837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- María Auxiliadora Aparicio
- Laboratory for the Neurobiology of Hearing, Neuroscience Institute of Castilla y León, University of Salamanca, Salamanca, Spain
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24
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Rykhlevskaia E, Gratton G, Fabiani M. Combining structural and functional neuroimaging data for studying brain connectivity: a review. Psychophysiology 2007; 45:173-87. [PMID: 17995910 DOI: 10.1111/j.1469-8986.2007.00621.x] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Different brain areas are thought to be integrated into large-scale networks to support cognitive function. Recent approaches for investigating structural organization and functional coordination within these networks involve measures of connectivity among brain areas. We review studies combining in vivo structural and functional brain connectivity data, where (a) structural connectivity analysis, mostly based on diffusion tensor imaging is paired with voxel-wise analysis of functional neuroimaging data or (b) the measurement of functional connectivity based on covariance analysis is guided/aided by structural connectivity data. These studies provide insights into the relationships between brain structure and function. Promising trends involve (a) studies where both functional and anatomical connectivity data are collected using high-resolution neuroimaging methods and (b) the development of advanced quantitative models of integration.
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Affiliation(s)
- Elena Rykhlevskaia
- Beckman Institute and Psychology Department, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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25
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Abstract
Congruent information conveyed over different sensory modalities often facilitates a variety of cognitive processes, including speech perception (Sumby & Pollack, 1954). Since auditory processing is substantially faster than visual processing, auditory-visual integration can occur over a surprisingly wide temporal window (Stein, 1998). We investigated the processing architecture mediating the integration of acoustic digit names with corresponding symbolic visual forms. The digits "1" or "2" were presented in auditory, visual, or bimodal format at several stimulus onset asynchronies (SOAs; 0, 75, 150, and 225 msec). The reaction times (RTs) for echoing unimodal auditory stimuli were approximately 100 msec faster than the RTs for naming their visual forms. Correspondingly, bimodal facilitation violated race model predictions, but only at SOA values greater than 75 msec. These results indicate that the acoustic and visual information are pooled prior to verbal response programming. However, full expression of this bimodal summation is dependent on the central coincidence of the visual and auditory inputs. These results are considered in the context of studies demonstrating multimodal activation of regions involved in speech production.
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26
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Bizley JK, Nodal FR, Bajo VM, Nelken I, King AJ. Physiological and anatomical evidence for multisensory interactions in auditory cortex. Cereb Cortex 2006; 17:2172-89. [PMID: 17135481 PMCID: PMC7116518 DOI: 10.1093/cercor/bhl128] [Citation(s) in RCA: 246] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Recent studies, conducted almost exclusively in primates, have shown that several cortical areas usually associated with modality-specific sensory processing are subject to influences from other senses. Here we demonstrate using single-unit recordings and estimates of mutual information that visual stimuli can influence the activity of units in the auditory cortex of anesthetized ferrets. In many cases, these units were also acoustically responsive and frequently transmitted more information in their spike discharge patterns in response to paired visual-auditory stimulation than when either modality was presented by itself. For each stimulus, this information was conveyed by a combination of spike count and spike timing. Even in primary auditory areas (primary auditory cortex [A1] and anterior auditory field [AAF]), approximately 15% of recorded units were found to have nonauditory input. This proportion increased in the higher level fields that lie ventral to A1/AAF and was highest in the anterior ventral field, where nearly 50% of the units were found to be responsive to visual stimuli only and a further quarter to both visual and auditory stimuli. Within each field, the pure-tone response properties of neurons sensitive to visual stimuli did not differ in any systematic way from those of visually unresponsive neurons. Neural tracer injections revealed direct inputs from visual cortex into auditory cortex, indicating a potential source of origin for the visual responses. Primary visual cortex projects sparsely to A1, whereas higher visual areas innervate auditory areas in a field-specific manner. These data indicate that multisensory convergence and integration are features common to all auditory cortical areas but are especially prevalent in higher areas.
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Affiliation(s)
- Jennifer K Bizley
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3PT, UK.
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27
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Castellote JM, Kumru H, Queralt A, Valls-Solé J. A startle speeds up the execution of externally guided saccades. Exp Brain Res 2006; 177:129-36. [PMID: 16944110 DOI: 10.1007/s00221-006-0659-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Accepted: 07/26/2006] [Indexed: 10/24/2022]
Abstract
The control of eye movements depends in part on subcortical motor centres. Gaze is often directed towards salient visual stimuli of our environment with no conscious voluntary commands. To further understand to what extent preprogrammed eye movements can be triggered subcortically, we carried out a study in normal volunteers to examine the effects of a startling auditory stimulus (SAS) on externally guided saccades. A peripheral visual cue was presented in the horizontal plane at a site distant 15 degrees from the fixation point, and subjects were instructed to make a saccade to it. SAS was presented together with the peripheral visual cue in 20% of trials. To force rapid visual fixation at the end of the saccade, targets were loaded with a second cue, a small arrow pointing towards the right or the left (or a neutral sign), not distinguishable with peripheral vision. Subjects were requested to perform a flexion/extension wrist movement, according to the direction of the arrow (or not to move if the second cue was the neutral sign). SAS presented together with the visual target caused a significant shortening of the latency of saccadic movements. The wrist movements performed as a response to the second cue had similar reaction times regardless of whether the trial contained a SAS or not. Our results show that voluntary saccades to peripheral targets are speeded up by activation of the startle circuit, and that this effect does not cause a significant disturbance in the execution of simple in-target cues. These results suggest that subcortical structures play a main role in preparation of externally guided saccades.
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Affiliation(s)
- Juan M Castellote
- Facultad de Ciencias de la Actividad Física y el Deporte, Universidad de Valencia, 46010, Valencia, Spain
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28
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Isbell LA. Snakes as agents of evolutionary change in primate brains. J Hum Evol 2006; 51:1-35. [PMID: 16545427 DOI: 10.1016/j.jhevol.2005.12.012] [Citation(s) in RCA: 188] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2004] [Revised: 10/04/2005] [Accepted: 12/28/2005] [Indexed: 10/24/2022]
Abstract
Current hypotheses that use visually guided reaching and grasping to explain orbital convergence, visual specialization, and brain expansion in primates are open to question now that neurological evidence reveals no correlation between orbital convergence and the visual pathway in the brain that is associated with reaching and grasping. An alternative hypothesis proposed here posits that snakes were ultimately responsible for these defining primate characteristics. Snakes have a long, shared evolutionary existence with crown-group placental mammals and were likely to have been their first predators. Mammals are conservative in the structures of the brain that are involved in vigilance, fear, and learning and memory associated with fearful stimuli, e.g., predators. Some of these areas have expanded in primates and are more strongly connected to visual systems. However, primates vary in the extent of brain expansion. This variation is coincident with variation in evolutionary co-existence with the more recently evolved venomous snakes. Malagasy prosimians have never co-existed with venomous snakes, New World monkeys (platyrrhines) have had interrupted co-existence with venomous snakes, and Old World monkeys and apes (catarrhines) have had continuous co-existence with venomous snakes. The koniocellular visual pathway, arising from the retina and connecting to the lateral geniculate nucleus, the superior colliculus, and the pulvinar, has expanded along with the parvocellular pathway, a visual pathway that is involved with color and object recognition. I suggest that expansion of these pathways co-occurred, with the koniocellular pathway being crucially involved (among other tasks) in pre-attentional visual detection of fearful stimuli, including snakes, and the parvocellular pathway being involved (among other tasks) in protecting the brain from increasingly greater metabolic demands to evolve the neural capacity to detect such stimuli quickly. A diet that included fruits or nectar (though not to the exclusion of arthropods), which provided sugars as a neuroprotectant, may have been a required preadaptation for the expansion of such metabolically active brains. Taxonomic differences in evolutionary exposure to venomous snakes are associated with similar taxonomic differences in rates of evolution in cytochrome oxidase genes and in the metabolic activity of cytochrome oxidase proteins in at least some visual areas in the brains of primates. Raptors that specialize in eating snakes have larger eyes and greater binocularity than more generalized raptors, and provide non-mammalian models for snakes as a selective pressure on primate visual systems. These models, along with evidence from paleobiogeography, neuroscience, ecology, behavior, and immunology, suggest that the evolutionary arms race begun by constrictors early in mammalian evolution continued with venomous snakes. Whereas other mammals responded by evolving physiological resistance to snake venoms, anthropoids responded by enhancing their ability to detect snakes visually before the strike.
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Affiliation(s)
- Lynne A Isbell
- Department of Anthropology, University of California, Davis, 95616, USA.
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Jiang W, Jiang H, Stein BE. Neonatal cortical ablation disrupts multisensory development in superior colliculus. J Neurophysiol 2005; 95:1380-96. [PMID: 16267111 PMCID: PMC1538963 DOI: 10.1152/jn.00880.2005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The ability of cat superior colliculus (SC) neurons to synthesize information from different senses depends on influences from two areas of the cortex: the anterior ectosylvian sulcus (AES) and the rostral lateral suprasylvian sulcus (rLS). Reversibly deactivating the inputs to the SC from either of these areas in normal adults severely compromises this ability and the SC-mediated behaviors that depend on it. In this study, we found that removal of these areas in neonatal animals precluded the normal development of multisensory SC processes. At maturity there was a substantial decrease in the incidence of multisensory neurons, and those multisensory neurons that did develop were highly abnormal. Their cross-modal receptive field register was severely compromised, as was their ability to integrate cross-modal stimuli. Apparently, despite the impressive plasticity of the neonatal brain, it cannot compensate for the early loss of these cortices. Surprisingly, however, neonatal removal of either AES or rLS had comparatively minor consequences on these properties. At maturity multisensory SC neurons were quite common: they developed the characteristic spatial register among their unisensory receptive fields and exhibited normal adult-like multisensory integration. These observations suggest that during early ontogeny, when the multisensory properties of SC neurons are being crafted, AES and rLS may have the ability to compensate for the loss of one another's cortico-collicular influences so that normal multisensory processes can develop in the SC.
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Affiliation(s)
- Wan Jiang
- Dept. of Neurobiology and Anatomy, Wake Forest Univ. School of Medicine, Winston-Salem, NC 27157-1010, USA
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30
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Bittencourt AS, Nakamura-Palacios EM, Mauad H, Tufik S, Schenberg LC. Organization of electrically and chemically evoked defensive behaviors within the deeper collicular layers as compared to the periaqueductal gray matter of the rat. Neuroscience 2005; 133:873-92. [PMID: 15916856 DOI: 10.1016/j.neuroscience.2005.03.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Revised: 03/04/2005] [Accepted: 03/11/2005] [Indexed: 10/25/2022]
Abstract
Stimulation of the periaqueductal gray matter (PAG) and the deeper layers of superior colliculus (SC) produces both freezing (tense immobility) and flight (trotting, galloping and jumping) behaviors along with exophthalmus (fully opened bulging eyes) and, less often, micturition and defecation. The topography of these behaviors within the distinct layers of SC remains unclear. Therefore, this study compared the defensive repertoire of intermediate (ILSC) and deep (DLSC) layers of SC to those of dorsolateral periaqueductal gray matter (DLPAG) and lateral periaqueductal gray matter (LPAG) [Neuroscience 125 (2004) 71]. Electrical stimulation was carried out through intensity- (0-70 microA) and frequency-varying (0-130 Hz) pulses. Chemical stimulation employed a slow microinfusion of N-methyl-d-aspartic acid (NMDA, 0-2.3 nmol, 0.5 nmol/min). Probability curves of intensity-, frequency- and NMDA-evoked behaviors, as well as the unbiased estimates of median stimuli, were obtained by threshold logistic analysis. Compared with the PAG, the most important differences were the lack of frequency-evoked jumping in both layers of SC and the lack of NMDA-evoked galloping in the ILSC. Moreover, although galloping and jumping were also elicited by NMDA stimulation of DLSC, effective doses were about three times higher than those of DLPAG, suggesting the spreading of the injectate to the latter structure. In contrast, exophthalmus, immobility and trotting were evoked throughout the tectum structures. However, whatever the response and kind of stimulus, the lowest thresholds were always found in the DLPAG and the highest ones in the ILSC. Besides, neither the appetitive, nor the offensive, muricide or male reproductive behaviors were produced by any kind of stimulus in the presence of appropriate targets. Accordingly, the present data suggest that the deeper layers of SC are most likely involved in the increased attentiveness (exophthalmus, immobility) or restlessness (trotting) behaviors that herald a full-blown flight reaction (galloping, jumping) mediated in the PAG.
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Affiliation(s)
- A S Bittencourt
- Departamento de Ciências Fisiológicas, Centro Biomédico, Edifício do Programa de Pós-Graduação em Ciências Fisiológicas, Universidade Federal do Espírito Santo, Av. Marechal Campos 1468 (Maruípe), 29043-125 Vitória, ES, Brazil
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Schenberg LC, Póvoa RMF, Costa ALP, Caldellas AV, Tufik S, Bittencourt AS. Functional specializations within the tectum defense systems of the rat. Neurosci Biobehav Rev 2005; 29:1279-98. [PMID: 16087233 DOI: 10.1016/j.neubiorev.2005.05.006] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Revised: 05/03/2005] [Accepted: 05/03/2005] [Indexed: 01/29/2023]
Abstract
Here we review the differential contribution of the periaqueductal gray matter (PAG) and superior colliculus (SC) to the generation of rat defensive behaviors. The results of studies involving sine-wave and rectangular pulse electrical stimulation and chemical (NMDA) stimulation are summarized. Stimulation of SC and PAG produced freezing and flight behaviors along with exophthalmus (fully opened bulged eyes), micturition and defecation. The columnar organization of the PAG was evident in the results obtained. Defecation was elicited primarily by lateral PAG stimulation, while the remaining defensive behaviors were similarly elicited by lateral and dorsolateral PAG stimulation, although with the lowest thresholds in the dorsolateral column. Conversely, the ventrolateral PAG did not appear to participate in unconditioned defensive behaviors, which were only elicited by high intensity stimulation likely to encroach on adjacent regions. In the SC, the most important differences relative to the PAG were the lack of stimulation-evoked jumping in both intermediate and deep layers, and of NMDA-evoked galloping in intermediate layers. Therefore, we conclude that the SC may be only involved in the increased attentiveness (exophthalmus, immobility) and restlessness (trotting) of prey species exposed to the cues of a nearby predator. These responses may be distinct from the full-blown flight reaction that is mediated by the dorsolateral and lateral PAG. However, other evidences suggest the possible influences of stimulation schedule, environment dimensions and rat strain in determining outcomes. Overall our results suggest a dynamically organized representation of defensive behaviors in the midbrain tectum.
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Affiliation(s)
- L C Schenberg
- Departamento de Ciências Fisiológicas--Centro Biomédico (Edifício do Programa de Pós-Graduação em Ciências Fisiológicas), Universidade Federal do Espírito Santo, Av. Marechal Campos 1468 (Maruípe), 29043-125, Vitória, ES, Brazil.
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Tardif E, Delacuisine B, Probst A, Clarke S. Intrinsic connectivity of human superior colliculus. Exp Brain Res 2005; 166:316-24. [PMID: 16032404 DOI: 10.1007/s00221-005-2373-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2004] [Accepted: 11/02/2004] [Indexed: 10/25/2022]
Abstract
The superior colliculus (SC) is believed to play an important role in sensorimotor integration and orienting behavior. It is classically divided into superficial layers predominantly containing visual neurons and deep layers containing multisensory and premotor neurons. Investigations of intrinsic connectivity within the SC in non-human species initially led to controversy regarding the existence of interlaminar connections between superficial and deep layers. It now seems more likely that such connections exist in a number of species, including non-human primates. In the latter, anatomical data concerning intrinsic SC connectivity are restricted to a limited number of intracellularly labeled neurons. No studies have been conducted to investigate the existence of intrinsic connections of human SC. In the present study, DiI (1,1'-dioctadecyl-3,3,3',3'- tetramethylindocarbocyanine perchlorate) and BDA (biotinylated dextran amine) were two tracers used in post-mortem human brains to examine intrinsic SC connections. Injections into the superficial layers revealed tangential connections within superficial layers and radial superficial-layer to deep-layer connections. Within superficial layers, horizontal connections were found over the entire rostro-caudal axis and were mostly directed laterally, i.e. toward the brachium of the inferior colliculus. Superficial-layer to deep-layer connections were more prominent in sections containing the injection site or located close to it. In these sections, an axon bundle having roughly the same diameter as the injection site crossed all deep layers, and individual axons displayed en passant or terminal boutons. The present results suggest that intrinsic connections within superficial layers and radial superficial-layers to deep-layers exist in human SC. The putative roles of these connections are discussed with regard to visual receptive field organization, as well as visuomotor and multisensory integration.
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Affiliation(s)
- Eric Tardif
- Division de Neuropsychologie, CHUV, 1011, Lausanne, Switzerland.
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Mascia MM, Valls-Solé J, Martí MJ, Salazar G. Sensorimotor integration in patients with parkinsonian type multisystem atrophy. J Neurol 2005; 252:473-81. [PMID: 15726255 DOI: 10.1007/s00415-005-0678-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2004] [Revised: 09/08/2004] [Accepted: 10/05/2004] [Indexed: 10/25/2022]
Abstract
Sensorimotor integration is an essential feature of the central nervous system that contributes to the accurate performance of motor tasks. Some patients with multiple system atrophy with parkinsonian features (MSAp) exhibit clinical signs compatible with an abnormal central nervous system excitability to somatosensory inputs, such as action myoclonus or enhanced cutaneo-muscular reflexes. To investigate further the site where such dysfunction in sensorimotor integration takes place, we examined the inhibitory effects of a cutaneous afferent volley at two different levels of the motor system in 10 MSAp patients and in 10 age-matched healthy volunteers. Electrical digital nerve stimuli were given as the conditioning stimulus for the motor evoked potentials (MEP) elicited by transcranial magnetic stimulation in hand muscles, and for the blink reflex responses obtained in the orbicularis oculi muscles by supraorbital nerve stimulation. Intervals for the conditioning were 20 to 50 ms for the MEP and 90 to 110 ms for the blink reflex. The MEP was significantly inhibited in test trials in healthy volunteers, reaching a mean of 32% of the baseline values at the ISI of 35 ms. Significant inhibition occurred also in the blink reflex, in which the R2 response was a mean of 12% of baseline values at the ISI of 100 ms. The inhibitory effects were abnormally reduced in 8 patients on the MEP, and in 7 patients on the blink reflex. There were significant group differences between patients and control subjects in the size of the conditioned MEP and blink reflex. These results suggest that sensorimotor integration is abnormal in patients with MSAp in at least two central nervous system sites: the sensorimotor cortex, and the brainstem reticular formation.
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Affiliation(s)
- M M Mascia
- Unitat d'EMG. Servei de Neurologia, Hospital Clínic, Villarroel,170, Barcelona 08036, Spain.
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Meredith MA, King AJ. Spatial distribution of functional superficial-deep connections in the adult ferret superior colliculus. Neuroscience 2005; 128:861-70. [PMID: 15464292 DOI: 10.1016/j.neuroscience.2004.06.060] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2004] [Indexed: 11/26/2022]
Abstract
Numerous studies have identified connections between the superficial visual and deeper multisensory layers of the superior colliculus (SC), but the functional distribution of the superficial-deep projection has not been mapped. This question was assessed in the present study using extracellular electrophysiological stimulation and recording techniques. In vitro slices from adult ferrets were used to functionally map the rostro-caudal, medio-lateral, and dorso-ventral distribution of these superficial-deep connections. For each coronal (n=6) or parasagittal (n=10) slice, single and multi-unit responses to electrical stimulation of a point in the superficial layers were systematically recorded at different locations along a grid (approximately 300 microm intervals) across the slice. Recording sites with similar activation thresholds were grouped on the histological reconstruction of each slice to plot the functional access of superficial stimulation site to the deeper layers. Low intensity stimulation (defined as a current threshold < or =75 microA) activated areas of the subjacent intermediate layers in most cases (75%; 12/16). Higher intensity stimuli (> 75-600 microA) accessed larger areas which, in 50% of the slices, extended into the deepest layers of the SC. However, regardless of the rostro-caudal or medio-lateral position of the superficial layer stimulation site, the proportion of the deeper layers activated remained remarkably constant, although the volume of activated deep layer tissue was shifted in each case toward the central regions of the SC. This last observation argues against the precise alignment of the superficial and deep layer visual maps, suggesting instead that the arrangement of the superficial layer projection may more closely relate to the organization of deep layer auditory and/or somatosensory representations.
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Affiliation(s)
- M A Meredith
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298-0709, USA
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Skaliora I, Doubell TP, Holmes NP, Nodal FR, King AJ. Functional Topography of Converging Visual and Auditory Inputs to Neurons in the Rat Superior Colliculus. J Neurophysiol 2004; 92:2933-46. [PMID: 15229210 DOI: 10.1152/jn.00450.2004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have used a slice preparation of the infant rat midbrain to examine converging inputs onto neurons in the deeper multisensory layers of the superior colliculus (dSC). Electrical stimulation of the superficial visual layers (sSC) and of the auditory nucleus of the brachium of the inferior colliculus (nBIC) evoked robust monosynaptic responses in dSC cells. Furthermore, the inputs from the sSC were found to be topographically organized as early as the second postnatal week and thus before opening of the eyes and ear canals. This precocious topography was found to be sculpted by GABAA-mediated inhibition of a more widespread set of connections. Tracer injections in the nBIC, both in coronal slices as well as in hemisected brains, confirmed a robust projection originating in the nBIC with distinct terminals in the proximity of the cell bodies of dSC neurons. Combined stimulation of the sSC and nBIC sites revealed that the presumptive visual and auditory inputs are summed linearly. Finally, whereas either input on its own could manifest a significant degree of paired-pulse facilitation, temporally offset stimulation of the two sites revealed no synaptic interactions, indicating again that the two inputs function independently. Taken together, these data provide the first detailed intracellular analysis of convergent sensory inputs onto dSC neurons and form the basis for further exploration of multisensory integration and developmental plasticity.
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Affiliation(s)
- Irini Skaliora
- University Laboratory of Physiology, University of Oxford, Oxford OX1 3PT, UK.
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Hellmann B, Güntürkün O, Manns M. Tectal mosaic: Organization of the descending tectal projections in comparison to the ascending tectofugal pathway in the pigeon. J Comp Neurol 2004; 472:395-410. [PMID: 15065115 DOI: 10.1002/cne.20056] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The optic tectum of vertebrates is an essential relay station for visuomotor behavior and is characterized by a set of connections that comprises topographically ordered input from the eyes and an output that reaches premotor hindbrain regions. In the avian tectofugal system, different ascending cell classes have recently been identified based on their dendritic and axonal projection patterns, although comparable information about the descending cells is missing. By means of retrograde tracing, the present study describes the detailed morphology of tectal output neurons that constitute the descending tectobulbar and tectopontine pathways in pigeons. Descending cells were more numerous in the dorsal tectum and differed in terms of 1) their relative amount of ipsi- vs. contralateral projections, 2) the location of the efferent cell bodies within different tectal layers, and 3) their differential access to visual input via dendritic ramifications within the outer retinorecipient laminae. Thus, the descending tectal system is constituted by different cell classes presumably processing diverse aspects of the visual environment in a visual field-dependent manner. We demonstrate, based on a careful morphological analysis and on double-labeling experiments, that the descending pathways are largely separated from the ascending projections even when they arise from the same layers. These data support the concept that the tectum is arranged as a mosaic of multiple cell types with diverse input functions at the same location of the tectal map. Such an arrangement would enable the tectal projections onto diverse areas to be both retinotopically organized and functionally specific.
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Affiliation(s)
- Burkhard Hellmann
- Abteilung Biopsychologie, Institut für Kognitive Neurowissenschaft, Fakultät für Psychologie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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