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Mueller SA, Oler JA, Roseboom PH, Aggarwal N, Kenwood MM, Riedel MK, Elam VR, Olsen ME, DiFilippo AH, Christian BT, Hu X, Galvan A, Boehm MA, Michaelides M, Kalin NH. DREADD-mediated amygdala activation is sufficient to induce anxiety-like responses in young nonhuman primates. CURRENT RESEARCH IN NEUROBIOLOGY 2023; 5:100111. [PMID: 38020807 PMCID: PMC10663133 DOI: 10.1016/j.crneur.2023.100111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 09/11/2023] [Accepted: 09/25/2023] [Indexed: 12/01/2023] Open
Abstract
Anxiety disorders are among the most prevalent psychiatric disorders, with symptoms often beginning early in life. To model the pathophysiology of human pathological anxiety, we utilized Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) in a nonhuman primate model of anxious temperament to selectively increase neuronal activity of the amygdala. Subjects included 10 young rhesus macaques; 5 received bilateral infusions of AAV5-hSyn-HA-hM3Dq into the dorsal amygdala, and 5 served as controls. Subjects underwent behavioral testing in the human intruder paradigm following clozapine or vehicle administration, prior to and following surgery. Behavioral results indicated that clozapine treatment post-surgery increased freezing across different threat-related contexts in hM3Dq subjects. This effect was again observed approximately 1.9 years following surgery, indicating the long-term functional capacity of DREADD-induced neuronal activation. [11C]deschloroclozapine PET imaging demonstrated amygdala hM3Dq-HA specific binding, and immunohistochemistry revealed that hM3Dq-HA expression was most prominent in basolateral nuclei. Electron microscopy confirmed expression was predominantly on neuronal membranes. Together, these data demonstrate that activation of primate amygdala neurons is sufficient to induce increased anxiety-related behaviors, which could serve as a model to investigate pathological anxiety in humans.
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Affiliation(s)
- Sascha A.L. Mueller
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Jonathan A. Oler
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Patrick H. Roseboom
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Nakul Aggarwal
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Margaux M. Kenwood
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Marissa K. Riedel
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Victoria R. Elam
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Miles E. Olsen
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
| | - Alexandra H. DiFilippo
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Bradley T. Christian
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53705, USA
| | - Xing Hu
- Emory National Primate Research Center, Emory University, Atlanta, GA, 30329, USA
| | - Adriana Galvan
- Emory National Primate Research Center, Emory University, Atlanta, GA, 30329, USA
| | - Matthew A. Boehm
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Michael Michaelides
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Ned H. Kalin
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI, 53719, USA
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2
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Mueller SAL, Oler JA, Roseboom PH, Aggarwal N, Kenwood MM, Riedel MK, Elam VR, Olsen ME, DiFilippo AH, Christian BT, Hu X, Galvan A, Boehm MA, Michaelides M, Kalin NH. DREADD-mediated amygdala activation is sufficient to induce anxiety-like responses in young nonhuman primates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.06.543911. [PMID: 37333300 PMCID: PMC10274719 DOI: 10.1101/2023.06.06.543911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Anxiety disorders are among the most prevalent psychiatric disorders, with symptoms often beginning early in life. To model the pathophysiology of human pathological anxiety, we utilized Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) in a nonhuman primate model of anxious temperament to selectively increase neuronal activity of the amygdala. Subjects included 10 young rhesus macaques; 5 received bilateral infusions of AAV5-hSyn-HA-hM3Dq into the dorsal amygdala, and 5 served as controls. Subjects underwent behavioral testing in the human intruder paradigm following clozapine or vehicle administration, prior to and following surgery. Behavioral results indicated that clozapine treatment post-surgery increased freezing across different threat-related contexts in hM3Dq subjects. This effect was again observed approximately 1.9 years following surgery, indicating the long-term functional capacity of DREADD-induced neuronal activation. [11C]deschloroclozapine PET imaging demonstrated amygdala hM3Dq-HA specific binding, and immunohistochemistry revealed that hM3Dq-HA expression was most prominent in basolateral nuclei. Electron microscopy confirmed expression was predominantly on neuronal membranes. Together, these data demonstrate that activation of primate amygdala neurons is sufficient to induce increased anxiety-related behaviors, which could serve as a model to investigate pathological anxiety in humans.
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Affiliation(s)
- Sascha A L Mueller
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Jonathan A Oler
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Patrick H Roseboom
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Nakul Aggarwal
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Margaux M Kenwood
- Department of Psychiatry, Weill Cornell Medical College, New York, NY 10065, USA
| | - Marissa K Riedel
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Victoria R Elam
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Miles E Olsen
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
| | - Alexandra H DiFilippo
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Bradley T Christian
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
- Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Xing Hu
- Emory National Primate Research Center, Emory University, Atlanta, GA 30329, USA
| | - Adriana Galvan
- Emory National Primate Research Center, Emory University, Atlanta, GA 30329, USA
| | - Matthew A Boehm
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Michael Michaelides
- Biobehavioral Imaging and Molecular Neuropsychopharmacology Unit, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Ned H Kalin
- Department of Psychiatry and the HealthEmotions Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, WI 53719, USA
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3
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Sonkusare S, Qiong D, Zhao Y, Liu W, Yang R, Mandali A, Manssuer L, Zhang C, Cao C, Sun B, Zhan S, Voon V. Frequency dependent emotion differentiation and directional coupling in amygdala, orbitofrontal and medial prefrontal cortex network with intracranial recordings. Mol Psychiatry 2022; 28:1636-1646. [PMID: 36460724 DOI: 10.1038/s41380-022-01883-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 11/04/2022] [Accepted: 11/10/2022] [Indexed: 12/04/2022]
Abstract
The amygdala, orbitofrontal cortex (OFC) and medial prefrontal cortex (mPFC) form a crucial part of the emotion circuit, yet their emotion induced responses and interactions have been poorly investigated with direct intracranial recordings. Such high-fidelity signals can uncover precise spectral dynamics and frequency differences in valence processing allowing novel insights on neuromodulation. Here, leveraging the unique spatio-temporal advantages of intracranial electroencephalography (iEEG) from a cohort of 35 patients with intractable epilepsy (with 71 contacts in amygdala, 31 in OFC and 43 in mPFC), we assessed the spectral dynamics and interactions between the amygdala, OFC and mPFC during an emotional picture viewing task. Task induced activity showed greater broadband gamma activity in the negative condition compared to positive condition in all the three regions. Similarly, beta activity was increased in the negative condition in the amygdala and OFC while decreased in mPFC. Furthermore, beta activity of amygdala showed significant negative association with valence ratings. Critically, model-based computational analyses revealed unidirectional connectivity from mPFC to the amygdala and bidirectional communication between OFC-amygdala and OFC-mPFC. Our findings provide direct neurophysiological evidence for a much-posited model of top-down influence of mPFC over amygdala and a bidirectional influence between OFC and the amygdala. Altogether, in a relatively large sample size with human intracranial neuronal recordings, we highlight valence-dependent spectral dynamics and dyadic coupling within the amygdala-mPFC-OFC network with implications for potential targeted neuromodulation in emotion processing.
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Affiliation(s)
- Saurabh Sonkusare
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Department of Psychiatry, University of Cambridge, Cambridge, UK.,Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Ding Qiong
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Fudan University, Ministry of Education, Shanghai, China
| | - Yijie Zhao
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China.,Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Fudan University, Ministry of Education, Shanghai, China
| | - Wei Liu
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ruoqi Yang
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Alekhya Mandali
- Department of Psychiatry, University of Cambridge, Cambridge, UK.,Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.,MRC Brain Network Dynamics Unit, University of Oxford, Oxford, UK
| | - Luis Manssuer
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Department of Psychiatry, University of Cambridge, Cambridge, UK.,Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Chencheng Zhang
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chunyan Cao
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Bomin Sun
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shikun Zhan
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Valerie Voon
- Department of Psychiatry, University of Cambridge, Cambridge, UK. .,Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China.
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4
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Kung PH, Soriano-Mas C, Steward T. The influence of the subcortex and brain stem on overeating: How advances in functional neuroimaging can be applied to expand neurobiological models to beyond the cortex. Rev Endocr Metab Disord 2022; 23:719-731. [PMID: 35380355 PMCID: PMC9307542 DOI: 10.1007/s11154-022-09720-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/21/2022] [Indexed: 12/13/2022]
Abstract
Functional neuroimaging has become a widely used tool in obesity and eating disorder research to explore the alterations in neurobiology that underlie overeating and binge eating behaviors. Current and traditional neurobiological models underscore the importance of impairments in brain systems supporting reward, cognitive control, attention, and emotion regulation as primary drivers for overeating. Due to the technical limitations of standard field strength functional magnetic resonance imaging (fMRI) scanners, human neuroimaging research to date has focused largely on cortical and basal ganglia effects on appetitive behaviors. The present review draws on animal and human research to highlight how neural signaling encoding energy regulation, reward-learning, and habit formation converge on hypothalamic, brainstem, thalamic, and striatal regions to contribute to overeating in humans. We also consider the role of regions such as the mediodorsal thalamus, ventral striatum, lateral hypothalamus and locus coeruleus in supporting habit formation, inhibitory control of food craving, and attentional biases. Through these discussions, we present proposals on how the neurobiology underlying these processes could be examined using functional neuroimaging and highlight how ultra-high field 7-Tesla (7 T) fMRI may be leveraged to elucidate the potential functional alterations in subcortical networks. Focus is given to how interactions of these regions with peripheral endocannabinoids and neuropeptides, such as orexin, could be explored. Technical and methodological aspects regarding the use of ultra-high field 7 T fMRI to study eating behaviors are also reviewed.
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Affiliation(s)
- Po-Han Kung
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Victoria, Australia
| | - Carles Soriano-Mas
- Psychiatry and Mental Health Group, Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), Neuroscience Program, L'Hospitalet de Llobregat, Spain
- CIBERSAM, Carlos III Health Institute, Madrid, Spain
- Department of Social Psychology and Quantitative Psychology, University of Barcelona, Barcelona, Spain
| | - Trevor Steward
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC, Australia.
- Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Victoria, Australia.
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5
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Tsolias A, Medalla M. Muscarinic Acetylcholine Receptor Localization on Distinct Excitatory and Inhibitory Neurons Within the ACC and LPFC of the Rhesus Monkey. Front Neural Circuits 2022; 15:795325. [PMID: 35087381 PMCID: PMC8786743 DOI: 10.3389/fncir.2021.795325] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 12/09/2021] [Indexed: 12/14/2022] Open
Abstract
Acetylcholine (ACh) can act on pre- and post-synaptic muscarinic receptors (mAChR) in the cortex to influence a myriad of cognitive processes. Two functionally-distinct regions of the prefrontal cortex-the lateral prefrontal cortex (LPFC) and the anterior cingulate cortex (ACC)-are differentially innervated by ascending cholinergic pathways yet, the nature and organization of prefrontal-cholinergic circuitry in primates are not well understood. Using multi-channel immunohistochemical labeling and high-resolution microscopy, we found regional and laminar differences in the subcellular localization and the densities of excitatory and inhibitory subpopulations expressing m1 and m2 muscarinic receptors, the two predominant cortical mAChR subtypes, in the supragranular layers of LPFC and ACC in rhesus monkeys (Macaca mulatta). The subset of m1+/m2+ expressing SMI-32+ pyramidal neurons labeled in layer 3 (L3) was denser in LPFC than in ACC, while m1+/m2+ SMI-32+ neurons co-expressing the calcium-binding protein, calbindin (CB) was greater in ACC. Further, we found between-area differences in laminar m1+ dendritic expression, and m2+ presynaptic localization on cortico-cortical (VGLUT1+) and sub-cortical inputs (VGLUT2+), suggesting differential cholinergic modulation of top-down vs. bottom-up inputs in the two areas. While almost all inhibitory interneurons-identified by their expression of parvalbumin (PV+), CB+, and calretinin (CR+)-expressed m1+, the localization of m2+ differed by subtype and area. The ACC exhibited a greater proportion of m2+ inhibitory neurons compared to the LPFC and had a greater density of presynaptic m2+ localized on inhibitory (VGAT+) inputs targeting proximal somatodendritic compartments and axon initial segments of L3 pyramidal neurons. These data suggest a greater capacity for m2+-mediated cholinergic suppression of inhibition in the ACC compared to the LPFC. The anatomical localization of muscarinic receptors on ACC and LPFC micro-circuits shown here contributes to our understanding of diverse cholinergic neuromodulation of functionally-distinct prefrontal areas involved in goal-directed behavior, and how these interactions maybe disrupted in neuropsychiatric and neurological conditions.
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Affiliation(s)
- Alexandra Tsolias
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
| | - Maria Medalla
- Department of Anatomy & Neurobiology, Boston University School of Medicine, Boston, MA, United States
- Center for Systems Neuroscience, Boston University, Boston, MA, United States
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6
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Preuss TM, Wise SP. Evolution of prefrontal cortex. Neuropsychopharmacology 2022; 47:3-19. [PMID: 34363014 PMCID: PMC8617185 DOI: 10.1038/s41386-021-01076-5] [Citation(s) in RCA: 68] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/01/2021] [Accepted: 06/15/2021] [Indexed: 02/07/2023]
Abstract
Subdivisions of the prefrontal cortex (PFC) evolved at different times. Agranular parts of the PFC emerged in early mammals, and rodents, primates, and other modern mammals share them by inheritance. These are limbic areas and include the agranular orbital cortex and agranular medial frontal cortex (areas 24, 32, and 25). Rodent research provides valuable insights into the structure, functions, and development of these shared areas, but it contributes less to parts of the PFC that are specific to primates, namely, the granular, isocortical PFC that dominates the frontal lobe in humans. The first granular PFC areas evolved either in early primates or in the last common ancestor of primates and tree shrews. Additional granular PFC areas emerged in the primate stem lineage, as represented by modern strepsirrhines. Other granular PFC areas evolved in simians, the group that includes apes, humans, and monkeys. In general, PFC accreted new areas along a roughly posterior to anterior trajectory during primate evolution. A major expansion of the granular PFC occurred in humans in concert with other association areas, with modifications of corticocortical connectivity and gene expression, although current evidence does not support the addition of a large number of new, human-specific PFC areas.
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Affiliation(s)
- Todd M Preuss
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, 30329, USA.
| | - Steven P Wise
- Olschefskie Institute for the Neurobiology of Knowledge, Bethesda, MD, 20814, USA
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Wang J, John Y, Barbas H. Pathways for Contextual Memory: The Primate Hippocampal Pathway to Anterior Cingulate Cortex. Cereb Cortex 2021; 31:1807-1826. [PMID: 33207365 PMCID: PMC7869091 DOI: 10.1093/cercor/bhaa333] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/13/2020] [Accepted: 10/14/2020] [Indexed: 12/27/2022] Open
Abstract
The anterior cingulate cortex (ACC) is one of the few prefrontal areas that receives robust direct hippocampal terminations. This pathway may enable current context and past experience to influence goal-directed actions and emotional regulation by prefrontal cortices. We investigated the still ill-understood organization of the pathway from anterior hippocampus to ACC (A24a, A25, A32) to identify laminar termination patterns and their postsynaptic excitatory and inhibitory targets from system to synapse in rhesus monkeys. The densest hippocampal terminations targeted posterior A25, a region that is involved in affective and autonomic regulation. Hippocampal terminations innervated mostly excitatory neurons (~90%), suggesting strong excitatory effects. Among the smaller fraction of inhibitory targets, hippocampal terminations in A25 preferentially innervated calretinin neurons, a pattern that differs markedly from rodents. Further, hippocampal terminations innervated spines with D1 receptors, particularly in the deep layers of A25, where D1 receptors are enriched in comparison with the upper layers. The proximity of hippocampal terminations to D1 receptors may enable dopamine to enhance information transfer from the hippocampus to A25 and contribute to dopaminergic influence downstream on goal-directed action and emotional control by prefrontal cortices, in processes that may be disrupted by excessive dopamine release during uncontrollable stress.
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Affiliation(s)
- Jingyi Wang
- Department of Health Sciences, Neural Systems Laboratory, Boston University, Boston, MA 02215, USA
| | - Yohan John
- Department of Health Sciences, Neural Systems Laboratory, Boston University, Boston, MA 02215, USA
| | - Helen Barbas
- Department of Health Sciences, Neural Systems Laboratory, Boston University, Boston, MA 02215, USA
- Graduate Program in Neuroscience, Boston University and School of Medicine, Boston, MA 02215, USA
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8
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Deming P, Dargis M, Haas BW, Brook M, Decety J, Harenski C, Kiehl KA, Koenigs M, Kosson DS. Psychopathy is associated with fear-specific reductions in neural activity during affective perspective-taking. Neuroimage 2020; 223:117342. [PMID: 32898678 PMCID: PMC9831240 DOI: 10.1016/j.neuroimage.2020.117342] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 08/18/2020] [Accepted: 08/31/2020] [Indexed: 01/13/2023] Open
Abstract
Psychopathic individuals are notorious for their callous disregard for others' emotions. Prior research has linked psychopathy to deficits in affective mechanisms underlying empathy (e.g., affective sharing), yet research relating psychopathy to cognitive mechanisms underlying empathy (e.g., affective perspective-taking and Theory of Mind) requires further clarification. To elucidate the neurobiology of cognitive mechanisms of empathy in psychopathy, we administered an fMRI task and tested for global as well as emotion-specific deficits in affective perspective-taking. Adult male incarcerated offenders (N = 94) viewed images of two people interacting, with one individual's face obscured by a shape. Participants were cued to either identify the emotion of the obscured individual or identify the shape from one of two emotion or shape choices presented on each trial. Target emotions included anger, fear, happiness, sadness, and neutral. Contrary to predictions, psychopathy was unrelated to neural activity in the Affective Perspective-taking > Shape contrast. In line with predictions, psychopathy was negatively related to task accuracy during affective perspective-taking for fear, happiness, and sadness. Psychopathy was related to reduced hemodynamic activity exclusively during fear perspective-taking in several areas: left anterior insula extending into posterior orbitofrontal cortex, right precuneus, left superior parietal lobule, and left superior occipital cortex. Although much prior research has emphasized psychopathy-related abnormalities in affective mechanisms mediating empathy, current results add to growing evidence of psychopathy-related abnormalities in a cognitive mechanism related to empathy. These findings highlight brain regions that are hypoactive in psychopathy when explicitly processing another's fear.
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Affiliation(s)
- Philip Deming
- Department of Psychology, University of Wisconsin-Madison, 1202 West Johnson St., Madison, WI, United States
- Department of Psychiatry, University of Wisconsin-Madison, 6001 Research Park Blvd., Madison, Wisconsin, United States
| | - Monika Dargis
- Department of Psychology, University of Wisconsin-Madison, 1202 West Johnson St., Madison, WI, United States
- Department of Psychiatry, University of Wisconsin-Madison, 6001 Research Park Blvd., Madison, Wisconsin, United States
| | - Brian W. Haas
- Department of Psychology, University of Georgia, 125 Baldwin St., Athens, GA, United States
- Interdisciplinary Neuroscience Graduate Program, University of Georgia, S150 Paul D. Coverdell Center, Athens, GA, United States
| | - Michael Brook
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, 420 E Superior St., Chicago, Illinois, United States
| | - Jean Decety
- Department of Psychology, University of Chicago, 5848 South University Ave., Chicago, Illinois, United States
| | - Carla Harenski
- The Mind Research Network and Lovelace Biomedical, 1101 Yale Blvd. NE, Albuquerque, New Mexico, United States
- Department of Psychology, University of New Mexico, 1 University of New Mexico, Albuquerque, New Mexico, United States
| | - Kent A. Kiehl
- The Mind Research Network and Lovelace Biomedical, 1101 Yale Blvd. NE, Albuquerque, New Mexico, United States
- Department of Psychology, University of New Mexico, 1 University of New Mexico, Albuquerque, New Mexico, United States
| | - Michael Koenigs
- Department of Psychiatry, University of Wisconsin-Madison, 6001 Research Park Blvd., Madison, Wisconsin, United States
| | - David S. Kosson
- Department of Psychology, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
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9
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Lee M, Mueller A, Moore T. Differences in Noradrenaline Receptor Expression Across Different Neuronal Subtypes in Macaque Frontal Eye Field. Front Neuroanat 2020; 14:574130. [PMID: 33328901 PMCID: PMC7732642 DOI: 10.3389/fnana.2020.574130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/16/2020] [Indexed: 11/14/2022] Open
Abstract
Cognitive functions such as attention and working memory are modulated by noradrenaline receptors in the prefrontal cortex (PFC). The frontal eye field (FEF) has been shown to play an important role in visual spatial attention. However, little is known about the underlying circuitry. The aim of this study was to characterize the expression of noradrenaline receptors on different pyramidal neuron and inhibitory interneuron subtypes in macaque FEF. Using immunofluorescence, we found broad expression of noradrenaline receptors across all layers of the FEF. Differences in the expression of different noradrenaline receptors were observed across different inhibitory interneuron subtypes. No significant differences were observed in the expression of noradrenaline receptors across different pyramidal neuron subtypes. However, we found that putative long-range projecting pyramidal neurons expressed all noradrenaline receptor subtypes at a much higher proportion than any of the other neuronal subtypes. Nearly all long-range projecting pyramidal neurons expressed all types of noradrenaline receptor, suggesting that there is no receptor-specific machinery acting on these long-range projecting pyramidal neurons. This pattern of expression among long-range projecting pyramidal neurons suggests a mechanism by which noradrenergic modulation of FEF activity influences attention and working memory.
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Affiliation(s)
- Max Lee
- Department of Neurobiology, Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, United States
| | - Adrienne Mueller
- Department of Neurobiology, Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, United States
| | - Tirin Moore
- Department of Neurobiology, Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, United States
- Department of Neurobiology, Stanford University, Stanford, CA, United States
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10
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Liu X, Bautista J, Liu E, Zikopoulos B. Imbalance of laminar-specific excitatory and inhibitory circuits of the orbitofrontal cortex in autism. Mol Autism 2020; 11:83. [PMID: 33081829 PMCID: PMC7574354 DOI: 10.1186/s13229-020-00390-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 10/06/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The human orbitofrontal cortex (OFC) is involved in assessing the emotional significance of events and stimuli, emotion-based learning, allocation of attentional resources, and social cognition. Little is known about the structure, connectivity and excitatory/inhibitory circuit interactions underlying these diverse functions in human OFC, as well as how the circuit is disrupted in individuals with autism spectrum disorder (ASD). METHODS We used post-mortem brain tissue from neurotypical adults and individuals with ASD. We examined the morphology and distribution of myelinated axons across cortical layers in OFC, at the single axon level, as a proxy of excitatory pathways. In the same regions, we also examined the laminar distribution of all neurons and neurochemically- and functionally-distinct inhibitory neurons that express the calcium-binding proteins parvalbumin (PV), calbindin (CB), and calretinin (CR). RESULTS We found that the density of myelinated axons increased consistently towards layer 6, while the average axon diameter did not change significantly across layers in both groups. However, both the density and diameter of myelinated axons were significantly lower in the ASD group compared with the Control group. The distribution pattern and density of the three major types of inhibitory neurons was comparable between groups, but there was a significant reduction in the density of excitatory neurons across OFC layers in ASD. LIMITATIONS This study is limited by the availability of human post-mortem tissue optimally processed for high-resolution microscopy and immunolabeling, especially from individuals with ASD. CONCLUSIONS The balance between excitation and inhibition in OFC is at the core of its function, assessing and integrating emotional and social cues with internal states and external inputs. Our preliminary results provide evidence for laminar-specific changes in the ratio of excitation/inhibition in OFC of adults with ASD, with an overall weakening and likely disorganization of excitatory signals and a relative strengthening of local inhibition. These changes likely underlie pathology of major OFC communications with limbic or other cortices and the amygdala in individuals with ASD, and may provide the anatomic basis for disrupted transmission of signals for social interactions and emotions in autism.
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Affiliation(s)
- Xuefeng Liu
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave., Room 401D, Boston, MA, 02215, USA
| | - Julied Bautista
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave., Room 401D, Boston, MA, 02215, USA
| | - Edward Liu
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave., Room 401D, Boston, MA, 02215, USA
| | - Basilis Zikopoulos
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University, 635 Commonwealth Ave., Room 401D, Boston, MA, 02215, USA. .,Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA. .,Graduate Program in Neuroscience, Boston University, Boston, MA, USA.
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11
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Folloni D, Sallet J, Khrapitchev AA, Sibson N, Verhagen L, Mars RB. Dichotomous organization of amygdala/temporal-prefrontal bundles in both humans and monkeys. eLife 2019; 8:e47175. [PMID: 31689177 PMCID: PMC6831033 DOI: 10.7554/elife.47175] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 09/12/2019] [Indexed: 12/23/2022] Open
Abstract
The interactions of anterior temporal structures, and especially the amygdala, with the prefrontal cortex are pivotal to learning, decision-making, and socio-emotional regulation. A clear anatomical description of the organization and dissociation of fiber bundles linking anterior temporal cortex/amygdala and prefrontal cortex in humans is still lacking. Using diffusion imaging techniques, we reconstructed fiber bundles between these anatomical regions in human and macaque brains. First, by studying macaques, we assessed which aspects of connectivity known from tracer studies could be identified with diffusion imaging. Second, by comparing diffusion imaging results in humans and macaques, we estimated the patterns of fibers coursing between human amygdala and prefrontal cortex and compared them with those in the monkey. In posterior prefrontal cortex, we observed a prominent and well-preserved bifurcation of bundles into primarily two fiber systems-an amygdalofugal path and an uncinate path-in both species. This dissociation fades away in more rostral prefrontal regions.
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Affiliation(s)
- Davide Folloni
- Wellcome Centre for Integrative Neuroimaging (WIN),Department of Experimental PsychologyUniversity of OxfordOxfordUnited Kingdom
- Wellcome Centre for Integrative Neuroimaging (WIN), Centre for Functional MRI of the Brain (FMRIB),Nuffield Department of Clinical NeurosciencesJohn Radcliffe Hospital, University of OxfordOxfordUnited Kingdom
| | - Jerome Sallet
- Wellcome Centre for Integrative Neuroimaging (WIN),Department of Experimental PsychologyUniversity of OxfordOxfordUnited Kingdom
- Wellcome Centre for Integrative Neuroimaging (WIN), Centre for Functional MRI of the Brain (FMRIB),Nuffield Department of Clinical NeurosciencesJohn Radcliffe Hospital, University of OxfordOxfordUnited Kingdom
| | - Alexandre A Khrapitchev
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation OncologyUniversity of OxfordOxfordUnited Kingdom
| | - Nicola Sibson
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation OncologyUniversity of OxfordOxfordUnited Kingdom
| | - Lennart Verhagen
- Wellcome Centre for Integrative Neuroimaging (WIN),Department of Experimental PsychologyUniversity of OxfordOxfordUnited Kingdom
- Wellcome Centre for Integrative Neuroimaging (WIN), Centre for Functional MRI of the Brain (FMRIB),Nuffield Department of Clinical NeurosciencesJohn Radcliffe Hospital, University of OxfordOxfordUnited Kingdom
- Donders Institute for Brain, Cognition and BehaviourRadboud University NijmegenNijmegenNetherlands
| | - Rogier B Mars
- Wellcome Centre for Integrative Neuroimaging (WIN), Centre for Functional MRI of the Brain (FMRIB),Nuffield Department of Clinical NeurosciencesJohn Radcliffe Hospital, University of OxfordOxfordUnited Kingdom
- Donders Institute for Brain, Cognition and BehaviourRadboud University NijmegenNijmegenNetherlands
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12
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Specializations for reward-guided decision-making in the primate ventral prefrontal cortex. Nat Rev Neurosci 2019; 19:404-417. [PMID: 29795133 DOI: 10.1038/s41583-018-0013-4] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The estimated values of choices, and therefore decision-making based on those values, are influenced by both the chance that the chosen items or goods can be obtained (availability) and their current worth (desirability) as well as by the ability to link the estimated values to choices (a process sometimes called credit assignment). In primates, the prefrontal cortex (PFC) has been thought to contribute to each of these processes; however, causal relationships between particular subdivisions of the PFC and specific functions have been difficult to establish. Recent lesion-based research studies have defined the roles of two different parts of the primate PFC - the orbitofrontal cortex (OFC) and the ventral lateral frontal cortex (VLFC) - and their subdivisions in evaluating each of these factors and in mediating credit assignment during reward-based decision-making.
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13
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Frank DW, Costa VD, Averbeck BB, Sabatinelli D. Directional interconnectivity of the human amygdala, fusiform gyrus, and orbitofrontal cortex in emotional scene perception. J Neurophysiol 2019; 122:1530-1537. [PMID: 31166811 DOI: 10.1152/jn.00780.2018] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The perception of emotionally arousing scenes modulates neural activity in ventral visual areas via reentrant signals from the amygdala. The orbitofrontal cortex (OFC) shares dense interconnections with amygdala and has been strongly implicated in emotional stimulus processing in primates, but our understanding of the functional contribution of this region to emotional perception in humans is poorly defined. In this study we acquired targeted rapid functional imaging from lateral OFC, amygdala, and fusiform gyrus (FG) over multiple scanning sessions (resulting in over 1,000 trials per participant) in an effort to define the activation amplitude and directional connectivity among these regions during naturalistic scene perception. All regions of interest showed enhanced activation during emotionally arousing, compared with neutral scenes. In addition, we identified bidirectional connectivity between amygdala, FG, and OFC in the great majority of individual subjects, suggesting that human emotional perception is implemented in part via nonhierarchical causal interactions across these three regions.NEW & NOTEWORTHY Due to the practical limitations of noninvasive recording methodologies, there is a scarcity of data regarding the interactions of human amygdala and orbitofrontal cortex (OFC). Using rapid functional MRI sampling and directional connectivity, we found that the human amygdala influences emotional perception via distinct interactions with late-stage ventral visual cortex and OFC, in addition to distinct interactions between OFC and fusiform gyrus. Future efforts may leverage these patterns of directional connectivity to noninvasively distinguish clinical groups from controls with respect to network causal hierarchy.
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Affiliation(s)
- David W Frank
- Department of Behavioral Science, The University of Texas MD Anderson Cancer Center, Houston, Texas.,Department of Neuroscience, University of Georgia, Athens, Georgia
| | - Vincent D Costa
- Laboratory of Neuropsychology, National Institute of Mental Health, Bethesda, Maryland
| | - Bruno B Averbeck
- Laboratory of Neuropsychology, National Institute of Mental Health, Bethesda, Maryland
| | - Dean Sabatinelli
- Department of Neuroscience, University of Georgia, Athens, Georgia.,Department of Psychology, University of Georgia, Athens, Georgia
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14
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The Role of the Amygdala and the Ventromedial Prefrontal Cortex in Emotional Regulation: Implications for Post-traumatic Stress Disorder. Neuropsychol Rev 2019; 29:220-243. [DOI: 10.1007/s11065-019-09398-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 02/14/2019] [Indexed: 10/27/2022]
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15
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Paul S, Beucke JC, Kaufmann C, Mersov A, Heinzel S, Kathmann N, Simon D. Amygdala-prefrontal connectivity during appraisal of symptom-related stimuli in obsessive-compulsive disorder. Psychol Med 2019; 49:278-286. [PMID: 29622050 DOI: 10.1017/s003329171800079x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Cognitive models of obsessive-compulsive disorder (OCD) posit dysfunctional appraisal of disorder-relevant stimuli in patients, suggesting disturbances in the processes relying on amygdala-prefrontal connectivity. Recent neuroanatomical models add to the traditional view of dysfunction in corticostriatal circuits by proposing alterations in an affective circuit including amygdala-prefrontal connections. However, abnormalities in amygdala-prefrontal coupling during symptom provocation, and particularly during conditions that require stimulus appraisal, remain to be demonstrated directly. METHODS Amygdala-prefrontal connectivity was examined in unmedicated OCD patients during appraisal (v. distraction) of symptom-provoking stimuli compared with an emotional control condition. Subsequent analyses tested whether hypothesized connectivity alterations could be also identified during passive viewing and the resting state in two independent samples. RESULTS During symptom provocation, reductions in positive coupling between amygdala and orbitofrontal cortex were observed in OCD patients relative to healthy control participants during appraisal and passive viewing of OCD-relevant stimuli, whereas abnormally high amygdala-ventromedial prefrontal cortex coupling was found when appraisal was distracted by a secondary task. In contrast, there were no group differences in amygdala connectivity at rest. CONCLUSIONS Our finding of abnormal amygdala-prefrontal connectivity during appraisal of symptom-related (relative to generally aversive) stimuli is consistent with the involvement of affective circuits in the functional neuroanatomy of OCD. Aberrant connectivity can be assumed to impact stimulus appraisal and emotion regulation, but might also relate to fear extinction deficits, which have recently been described in OCD. Taken together, we propose to integrate abnormalities in amygdala-prefrontal coupling in affective models of OCD.
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Affiliation(s)
- Sandra Paul
- Department of Psychology,Humboldt-Universität zu Berlin,Germany
| | - Jan C Beucke
- Department of Psychology,Humboldt-Universität zu Berlin,Germany
| | | | - Anna Mersov
- Department of Speech-Language Pathology,University of Toronto,Canada
| | - Stephan Heinzel
- Department of Psychology,Humboldt-Universität zu Berlin,Germany
| | | | - Daniela Simon
- Department of Psychology,Humboldt-Universität zu Berlin,Germany
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16
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Barbas H, Wang J, Joyce MKP, García-Cabezas MÁ. Pathway mechanism for excitatory and inhibitory control in working memory. J Neurophysiol 2018; 120:2659-2678. [PMID: 30256740 DOI: 10.1152/jn.00936.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Humans engage in many daily activities that rely on working memory, the ability to hold and sequence information temporarily to accomplish a task. We focus on the process of working memory, based on circuit mechanisms for attending to relevant signals and suppressing irrelevant stimuli. We discuss that connections critically depend on the systematic variation in laminar structure across all cortical systems. Laminar structure is used to group areas into types regardless of their placement in the cortex, ranging from low-type agranular areas that lack layer IV to high-type areas that have six well-delineated layers. Connections vary in laminar distribution and strength based on the difference in type between linked areas, according to the "structural model" (Barbas H, Rempel-Clower N. Cereb Cortex 7: 635-646, 1997). The many possible pathways thus vary systematically by laminar distribution and strength, and they interface with excitatory neurons to select relevant stimuli and with functionally distinct inhibitory neurons that suppress activity at the site of termination. Using prefrontal pathways, we discuss how systematic architectonic variation gives rise to diverse pathways that can be recruited, along with amygdalar and hippocampal pathways that provide sensory, affective, and contextual information. The prefrontal cortex is also connected with thalamic nuclei that receive the output of the basal ganglia and cerebellum, which may facilitate fast sequencing of information. The complement of connections and their interface with distinct inhibitory neurons allows dynamic recruitment of areas and shifts in cortical rhythms to meet rapidly changing demands of sequential components of working memory tasks.
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Affiliation(s)
- Helen Barbas
- Neural Systems Laboratory, Boston University , Boston, Massachusetts.,Department of Health Sciences, Boston University , Boston, Massachusetts.,Graduate Program in Neuroscience, Boston University , Boston, Massachusetts
| | - Jingyi Wang
- Neural Systems Laboratory, Boston University , Boston, Massachusetts.,Department of Health Sciences, Boston University , Boston, Massachusetts
| | - Mary Kate P Joyce
- Neural Systems Laboratory, Boston University , Boston, Massachusetts.,Graduate Program in Neuroscience, Boston University , Boston, Massachusetts
| | - Miguel Ángel García-Cabezas
- Neural Systems Laboratory, Boston University , Boston, Massachusetts.,Department of Health Sciences, Boston University , Boston, Massachusetts
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17
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Specificity of Primate Amygdalar Pathways to Hippocampus. J Neurosci 2018; 38:10019-10041. [PMID: 30249799 DOI: 10.1523/jneurosci.1267-18.2018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 08/16/2018] [Accepted: 09/13/2018] [Indexed: 12/30/2022] Open
Abstract
The amygdala projects to hippocampus in pathways through which affective or social stimuli may influence learning and memory. We investigated the still unknown amygdalar termination patterns and their postsynaptic targets in hippocampus from system to synapse in rhesus monkeys of both sexes. The amygdala robustly innervated the stratum lacunosum-moleculare layer of cornu ammonis fields and uncus anteriorly. Sparser terminations in posterior hippocampus innervated the radiatum and pyramidal layers at the prosubicular/CA1 juncture. The terminations, which were larger than other afferents in the surrounding neuropil, position the amygdala to influence hippocampal input anteriorly, and its output posteriorly. Most amygdalar boutons (76-80%) innervated spines of excitatory hippocampal neurons, and most of the remaining innervated presumed inhibitory neurons, identified by morphology and label with parvalbumin or calretinin, which distinguished nonoverlapping neurochemical classes of hippocampal inhibitory neurons. In CA1, amygdalar axons innervated some calretinin neurons, which disinhibit pyramidal neurons. By contrast, in CA3 the amygdala innervated both calretinin and parvalbumin neurons; the latter strongly inhibit nearby excitatory neurons. In CA3, amygdalar pathways also made closely spaced dual synapses on excitatory neurons. The strong excitatory synapses in CA3 may facilitate affective context representations and trigger sharp-wave ripples associated with memory consolidation. When the amygdala is excessively activated during traumatic events, the specialized innervation of excitatory neurons and the powerful parvalbumin inhibitory neurons in CA3 may allow the suppression of activity of nearby neurons that receive weaker nonamygdalar input, leading to biased passage of highly charged affective stimuli and generalized fear.SIGNIFICANCE STATEMENT Strong pathways from the amygdala targeted the anterior hippocampus, and more weakly its posterior sectors, positioned to influence a variety of emotional and cognitive functions. In hippocampal field CA1, the amygdala innervated some calretinin neurons, which disinhibit excitatory neurons. By contrast, in CA3 the amygdala innervated calretinin as well as some of the powerful parvalbumin inhibitory neurons and may help balance the activity of neural ensembles to allow social interactions, learning, and memory. These results suggest that when the amygdala is hyperactive during emotional upheaval, it strongly activates excitatory hippocampal neurons and parvalbumin inhibitory neurons in CA3, which can suppress nearby neurons that receive weaker input from other sources, biasing the passage of stimuli with high emotional import and leading to generalized fear.
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18
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Wicker E, Turchi J, Malkova L, Forcelli PA. Mediodorsal thalamus is required for discrete phases of goal-directed behavior in macaques. eLife 2018; 7:37325. [PMID: 29848447 PMCID: PMC6010338 DOI: 10.7554/elife.37325] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/31/2018] [Indexed: 01/01/2023] Open
Abstract
Reward contingencies are dynamic: outcomes that were valued at one point may subsequently lose value. Action selection in the face of dynamic reward associations requires several cognitive processes: registering a change in value of the primary reinforcer, adjusting the value of secondary reinforcers to reflect the new value of the primary reinforcer, and guiding action selection to optimal choices. Flexible responding has been evaluated extensively using reinforcer devaluation tasks. Performance on this task relies upon amygdala, Areas 11 and 13 of orbitofrontal cortex (OFC), and mediodorsal thalamus (MD). Differential contributions of amygdala and Areas 11 and 13 of OFC to specific sub-processes have been established, but the role of MD in these sub-processes is unknown. Pharmacological inactivation of the macaque MD during specific phases of this task revealed that MD is required for reward valuation and action selection. This profile is unique, differing from both amygdala and subregions of the OFC. Most of us have experienced feeling full after a main course, only to discover that we somehow still have room for dessert. Eating a particular foodstuff to the point of satiety makes that item temporarily less appealing. This is an example of reward devaluation. We typically respond to this phenomenon by adjusting our behavior. We give up on the main course, for example, and turn our attention instead to dessert. This ability to adjust our actions based on changes in the value of their outcomes is a form of behavioral flexibility. Several brain regions contribute to behavioral flexibility. These include the amygdala, parts of the orbitofrontal cortex, and the mediodorsal thalamus. Wicker et al. have now explored the role of the mediodorsal thalamus by temporarily inactivating it in monkeys performing a task involving reward devaluation. The monkeys learned to associate one set of objects with peanuts and another with fruit. They were then given unlimited access to either peanuts or fruit. Finally, they were offered a choice between the two sets of objects. Like people who opt for dessert rather than another helping of a main course, the monkeys that had received peanuts chose the objects associated with fruit, and vice versa. Temporarily inactivating the mediodorsal thalamus prevented this change in behavior. This occurred if the inactivation took place while the monkeys had unlimited access to the reward, or if it took place while they were choosing between the two objects. The mediodorsal thalamus is thus required both to update the value of a reward and to select the best course of action. This is in contrast to the amygdala and the orbitofrontal cortex, which each support only one of these processes. Impaired behavioral flexibility is a hallmark of neuropsychiatric disorders, including addiction. Understanding the brain networks that support flexible responding may help improve the treatment of such disorders. As therapies that involve electrically stimulating the brain become more common, knowing which regions to avoid will be just as important as identifying new targets.
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Affiliation(s)
- Evan Wicker
- Department of Pharmacology and Physiology, Georgetown University, Washington, United States
| | - Janita Turchi
- Laboratory of Neuropsychology, National Institute of Mental Health, Maryland, United States
| | - Ludise Malkova
- Department of Pharmacology and Physiology, Georgetown University, Washington, United States.,Interdisciplinary Program in Neuroscience, Georgetown University, Washington, United States
| | - Patrick A Forcelli
- Department of Pharmacology and Physiology, Georgetown University, Washington, United States.,Interdisciplinary Program in Neuroscience, Georgetown University, Washington, United States.,Department of Neuroscience, Georgetown University, Washington, United States
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19
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Rich EL, Wallis JD. Spatiotemporal dynamics of information encoding revealed in orbitofrontal high-gamma. Nat Commun 2017; 8:1139. [PMID: 29074960 PMCID: PMC5658402 DOI: 10.1038/s41467-017-01253-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 08/31/2017] [Indexed: 01/22/2023] Open
Abstract
High-gamma signals mirror the tuning and temporal profiles of neurons near a recording electrode in sensory and motor areas. These frequencies appear to aggregate local neuronal activity, but it is unclear how this relationship affects information encoding in high-gamma activity (HGA) in cortical areas where neurons are heterogeneous in selectivity and temporal responses, and are not functionally clustered. Here we report that populations of neurons and HGA recorded from the orbitofrontal cortex (OFC) encode similar information, although there is little correspondence between signals recorded by the same electrode. HGA appears to aggregate heterogeneous neuron activity, such that the spiking of a single cell corresponds to only small increases in HGA. Interestingly, large-scale spatiotemporal dynamics are revealed in HGA, but less apparent in the population of single neurons. Overall, HGA is closely related to neuron activity in OFC, and provides a unique means of studying large-scale spatiotemporal dynamics of information processing. High gamma activity (HGA) and local neurons encode similar information, but it’s unclear if this is true when neurons are heterogeneous, as in the orbitofrontal cortex (OFC). Here, Rich & Wallis show that HGA in OFC is closely related to neuron firing, but reveals clearer spatiotemporal dynamics.
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Affiliation(s)
- Erin L Rich
- Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, 94720, USA. .,Friedman Brain Institute and Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA.
| | - Joni D Wallis
- Helen Wills Neuroscience Institute, University of California at Berkeley, Berkeley, CA, 94720, USA.,Department of Psychology, University of California at Berkeley, Berkeley, CA, 94720, USA
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20
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García-Cabezas MÁ, Barbas H. Anterior Cingulate Pathways May Affect Emotions Through Orbitofrontal Cortex. Cereb Cortex 2017; 27:4891-4910. [PMID: 27655930 PMCID: PMC6075591 DOI: 10.1093/cercor/bhw284] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 08/04/2016] [Accepted: 08/19/2016] [Indexed: 12/17/2022] Open
Abstract
The anterior cingulate cortex (ACC) and posterior orbitofrontal cortex (pOFC) are associated with emotional regulation. These regions are old in phylogeny and have widespread connections with eulaminate neocortices, intricately linking areas associated with emotion and cognition. The ACC and pOFC have distinct cortical and subcortical connections and are also interlinked, but the pattern of their connections-which may be used to infer the flow of information between them-is not well understood. Here we found that pathways from ACC area 32 innervated all pOFC areas with a significant proportion of large and efficient terminals, seen at the level of the system and the synapse. The pathway from area 32 targeted overwhelmingly elements of excitatory neurons in pOFC, with few postsynaptic sites found on presumed inhibitory neurons. Moreover, pathways from area 32 originated mostly in the upper layers and innervated preferentially the middle-deep layers of the least differentiated pOFC areas, in a pattern reminiscent of feedforward communication. Pathway terminations from area 32 overlapped in the deep layers of pOFC with output pathways that project to the thalamus and the amygdala, and may have cascading downstream effects on emotional and cognitive processes and their disruption in psychiatric disorders.
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Affiliation(s)
- Miguel Á. García-Cabezas
- Department of Health Sciences, Boston University, Neural Systems Lab, 635 Commonwealth Ave., Boston, MA02215, USA
| | - Helen Barbas
- Department of Health Sciences, Boston University, Neural Systems Lab, 635 Commonwealth Ave., Boston, MA02215, USA
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21
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Rockland KS. What do we know about laminar connectivity? Neuroimage 2017; 197:772-784. [PMID: 28729159 DOI: 10.1016/j.neuroimage.2017.07.032] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 07/13/2017] [Accepted: 07/15/2017] [Indexed: 12/17/2022] Open
Abstract
In this brief review, I attempt an overview of the main components of anatomical laminar-level connectivity. These are: extrinsic outputs, excitatory and inhibitory intrinsic connectivity, and intrinsic inputs. Supporting data are biased from the visual system of nonhuman primates (NHPs), but I have drawn as much as possible from a broader span in order to treat the important issue of area-specific variability. In a second part, I briefly discuss laminar connectivity in the context of network organization (feedforward/feedback cortical connections, and the major types of corticothalamic connections). I also point out anatomical issues in need of clarification, including more systematic, whole brain coverage of tracer injections; more data on anterogradely labeled terminations; more complete, area-specific quantitative data about projection neurons, and quantitative data on terminal density and convergence. Postsynaptic targets are largely unknown, but their identification is essential for understanding the finer analysis and principles of laminar patterns. Laminar resolution MRI offers a promising new tool for exploring laminar connectivity: it is potentially fast and macro-scale, and allows for repeated investigation under different stimulus conditions. Conversely, anatomical resolution, although detailed beyond the current level of MRI visualization, offers a rich trove for experimental design and interpretation of fMRI activation patterns.
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Affiliation(s)
- Kathleen S Rockland
- Department of Anatomy&Neurobiology, Boston University School of Medicine, 72 East Concord St., Boston, MA 02118, USA.
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22
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Shapiro LP, Parsons RG, Koleske AJ, Gourley SL. Differential expression of cytoskeletal regulatory factors in the adolescent prefrontal cortex: Implications for cortical development. J Neurosci Res 2017; 95:1123-1143. [PMID: 27735056 PMCID: PMC5352542 DOI: 10.1002/jnr.23960] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 09/04/2016] [Accepted: 09/12/2016] [Indexed: 12/27/2022]
Abstract
The prevalence of depression, anxiety, schizophrenia, and drug and alcohol use disorders peaks during adolescence. Further, up to 50% of "adult" mental health disorders emerge in adolescence. During adolescence, the prefrontal cortex (PFC) undergoes dramatic structural reorganization, in which dendritic spines and synapses are refined, pruned, and stabilized. Understanding the molecular mechanisms that underlie these processes should help to identify factors that influence the development of psychiatric illness. Here we briefly discuss the anatomical connections of the medial and orbital prefrontal cortex (mPFC and OFC, respectively). We then present original findings suggesting that dendritic spines on deep-layer excitatory neurons in the mouse mPFC and OFC prune at different adolescent ages, with later pruning in the OFC. In parallel, we used Western blotting to define levels of several cytoskeletal regulatory proteins during early, mid-, and late adolescence, focusing on tropomyosin-related kinase receptor B (TrkB) and β1-integrin-containing receptors and select signaling partners. We identified regional differences in the levels of several proteins in early and midadolescence that then converged in early adulthood. We also observed age-related differences in TrkB levels, both full-length and truncated isoforms, Rho-kinase 2, and synaptophysin in both PFC subregions. Finally, we identified changes in protein levels in the dorsal and ventral hippocampus that were distinct from those in the PFC. We conclude with a general review of the manner in which TrkB- and β1-integrin-mediated signaling influences neuronal structure in the postnatal brain. Elucidating the role of cytoskeletal regulatory factors throughout adolescence may identify critical mechanisms of PFC development. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Lauren P Shapiro
- Molecular and Systems Pharmacology, Emory University, Atlanta, Georgia
- Departments of Pediatrics and Psychiatry and Behavioral Sciences, Emory University School of Medicine, and Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
| | - Ryan G Parsons
- Department of Psychology and Neuroscience Institute, Graduate Program in Integrative Neuroscience, Program in Neuroscience, Stony Brook University, Stony Brook, New York
| | - Anthony J Koleske
- Department of Molecular Biophysics and Biochemistry, Department of Neurobiology, Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut
| | - Shannon L Gourley
- Departments of Pediatrics and Psychiatry and Behavioral Sciences, Emory University School of Medicine, and Yerkes National Primate Research Center, Emory University, Atlanta, Georgia
- Graduate Program in Neuroscience, Emory University, Atlanta, Georgia
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Posterior Orbitofrontal and Anterior Cingulate Pathways to the Amygdala Target Inhibitory and Excitatory Systems with Opposite Functions. J Neurosci 2017; 37:5051-5064. [PMID: 28411274 DOI: 10.1523/jneurosci.3940-16.2017] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/10/2017] [Accepted: 03/24/2017] [Indexed: 01/16/2023] Open
Abstract
The bidirectional dialogue of the primate posterior orbitofrontal cortex (pOFC) with the amygdala is essential in cognitive-emotional functions. The pOFC also sends a uniquely one-way excitatory pathway to the amygdalar inhibitory intercalated masses (IM), which inhibit the medial part of the central amygdalar nucleus (CeM). Inhibition of IM has the opposite effect, allowing amygdalar activation of autonomic structures and emotional arousal. Using multiple labeling approaches to identify pathways and their postsynaptic sites in the amygdala in rhesus monkeys, we found that the anterior cingulate cortex innervated mostly the basolateral and CeM amygdalar nuclei, poised to activate CeM for autonomic arousal. By contrast, a pathway from pOFC to IM exceeded all other pathways to the amygdala by density and size and proportion of large and efficient terminals. Moreover, whereas pOFC terminals in IM innervated each of the three distinct classes of inhibitory neurons, most targeted neurons expressing dopamine- and cAMP-regulated phosphoprotein (DARPP-32+), known to be modulated by dopamine. The predominant pOFC innervation of DARPP-32+ neurons suggests activation of IM and inhibition of CeM, resulting in modulated autonomic function. By contrast, inhibition of DARPP-32 neurons in IM by high dopamine levels disinhibits CeM and triggers autonomic arousal. The findings provide a mechanism to help explain how a strong pOFC pathway, which is poised to moderate activity of CeM, through IM, can be undermined by the high level of dopamine during stress, resulting in collapse of potent inhibitory mechanisms in the amygdala and heightened autonomic drive, as seen in chronic anxiety disorders.SIGNIFICANCE STATEMENT The dialogue between prefrontal cortex and amygdala allows thoughts and emotions to influence actions. The posterior orbitofrontal cortex sends a powerful pathway that targets a special class of amygdalar intercalated mass (IM) inhibitory neurons, whose wiring may help modulate autonomic function. By contrast, the anterior cingulate cortex innervates other amygdalar parts, activating circuits to help avoid danger. Most IM neurons in primates label for the protein DARPP-32, known to be activated or inhibited based on the level of dopamine. Stress markedly increases dopamine release and inhibits IM neurons, compromises prefrontal control of the amygdala, and sets off a general alarm system as seen in affective disorders, such as chronic anxiety and post-traumatic stress disorder.
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Hsu A, Luebke JI, Medalla M. Comparative ultrastructural features of excitatory synapses in the visual and frontal cortices of the adult mouse and monkey. J Comp Neurol 2017; 525:2175-2191. [PMID: 28256708 DOI: 10.1002/cne.24196] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 01/18/2017] [Accepted: 02/10/2017] [Indexed: 01/20/2023]
Abstract
The excitatory glutamatergic synapse is the principal site of communication between cortical pyramidal neurons and their targets, a key locus of action of many drugs, and highly vulnerable to dysfunction and loss in neurodegenerative disease. A detailed knowledge of the structure of these synapses in distinct cortical areas and across species is a prerequisite for understanding the anatomical underpinnings of cortical specialization and, potentially, selective vulnerability in neurological disorders. We used serial electron microscopy to assess the ultrastructural features of excitatory (asymmetric) synapses in the layers 2-3 (L2-3) neuropil of visual (V1) and frontal (FC) cortices of the adult mouse and compared findings to those in the rhesus monkey (V1 and lateral prefrontal cortex [LPFC]). Analyses of multiple ultrastructural variables revealed four organizational features. First, the density of asymmetric synapses does not differ between frontal and visual cortices in either species, but is significantly higher in mouse than in monkey. Second, the structural properties of asymmetric synapses in mouse V1 and FC are nearly identical, by stark contrast to the significant differences seen between monkey V1 and LPFC. Third, while the structural features of postsynaptic entities in mouse and monkey V1 do not differ, the size of presynaptic boutons are significantly larger in monkey V1. Fourth, both presynaptic and postsynaptic entities are significantly smaller in the mouse FC than in the monkey LPFC. The diversity of synaptic ultrastructural features demonstrated here have broad implications for the nature and efficacy of glutamatergic signaling in distinct cortical areas within and across species.
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Affiliation(s)
- Alexander Hsu
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts
| | - Jennifer I Luebke
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts
| | - Maria Medalla
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts
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Oya H, Howard MA, Magnotta VA, Kruger A, Griffiths TD, Lemieux L, Carmichael DW, Petkov CI, Kawasaki H, Kovach CK, Sutterer MJ, Adolphs R. Mapping effective connectivity in the human brain with concurrent intracranial electrical stimulation and BOLD-fMRI. J Neurosci Methods 2017; 277:101-112. [PMID: 28012852 PMCID: PMC5534177 DOI: 10.1016/j.jneumeth.2016.12.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/22/2016] [Accepted: 12/20/2016] [Indexed: 12/27/2022]
Abstract
BACKGROUND Understanding brain function requires knowledge of how one brain region causally influences another. This information is difficult to obtain directly in the human brain, and is instead typically inferred from resting-state fMRI. NEW METHOD Here, we demonstrate the safety and scientific promise of a novel and complementary approach: concurrent electrical stimulation and fMRI (es-fMRI) at 3T in awake neurosurgical patients with implanted depth electrodes. RESULTS We document the results of safety testing, actual experimental setup, and stimulation parameters, that safely and reliably evoke activation in distal structures through stimulation of amygdala, cingulate, or prefrontal cortex. We compare connectivity inferred from the evoked patterns of activation with that estimated from standard resting-state fMRI in the same patients: while connectivity patterns obtained with each approach are correlated, each method produces unique results. Response patterns were stable over the course of 11min of es-fMRI runs. COMPARISON WITH EXISTING METHOD: es-fMRI in awake humans yields unique information about effective connectivity, complementing resting-state fMRI. Although our stimulations were below the level of inducing any apparent behavioral or perceptual effects, a next step would be to use es-fMRI to modulate task performances. This would reveal the acute network-level changes induced by the stimulation that mediate the behavioral and cognitive effects seen with brain stimulation. CONCLUSIONS es-fMRI provides a novel and safe approach for mapping effective connectivity in the human brain in a clinical setting, and will inform treatments for psychiatric and neurodegenerative disorders that use deep brain stimulation.
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Affiliation(s)
- Hiroyuki Oya
- Department of Neurosurgery, Human Brain Research Laboratory, University of Iowa, Iowa City, IA 52241, USA.
| | - Matthew A Howard
- Department of Neurosurgery, Human Brain Research Laboratory, University of Iowa, Iowa City, IA 52241, USA
| | - Vincent A Magnotta
- Department of Radiology, University of Iowa College of Medicine, Iowa City, IA 52241, USA
| | - Anton Kruger
- Department of Electrical and Computer Engineering, University of Iowa College of Engineering, USA
| | | | - Louis Lemieux
- UCL Institute of Neurology, University College London, London, UK
| | | | | | - Hiroto Kawasaki
- Department of Neurosurgery, Human Brain Research Laboratory, University of Iowa, Iowa City, IA 52241, USA
| | - Christopher K Kovach
- Department of Neurosurgery, Human Brain Research Laboratory, University of Iowa, Iowa City, IA 52241, USA
| | - Matthew J Sutterer
- Department of Neurosurgery, Human Brain Research Laboratory, University of Iowa, Iowa City, IA 52241, USA
| | - Ralph Adolphs
- Division of Biology and Biological Engineering, California Institute of Technology, USA
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Ortega-Escobar J, Alcázar-Córcoles MÁ, Puente-Rodríguez L, Peñaranda-Ramos E. Psychopathy: Legal and neuroscientific aspects. ANUARIO DE PSICOLOGÍA JURÍDICA 2017. [DOI: 10.1016/j.apj.2017.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Zikopoulos B, John YJ, García-Cabezas MÁ, Bunce JG, Barbas H. The intercalated nuclear complex of the primate amygdala. Neuroscience 2016; 330:267-90. [PMID: 27256508 DOI: 10.1016/j.neuroscience.2016.05.052] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 05/09/2016] [Accepted: 05/26/2016] [Indexed: 12/20/2022]
Abstract
The organization of the inhibitory intercalated cell masses (IM) of the primate amygdala is largely unknown despite their key role in emotional processes. We studied the structural, topographic, neurochemical and intrinsic connectional features of IM neurons in the rhesus monkey brain. We found that the intercalated neurons are not confined to discrete cell clusters, but form a neuronal net that is interposed between the basal nuclei and extends to the dorsally located anterior, central, and medial nuclei of the amygdala. Unlike the IM in rodents, which are prominent in the anterior half of the amygdala, the primate inhibitory net stretched throughout the antero-posterior axis of the amygdala, and was most prominent in the central and posterior extent of the amygdala. There were two morphologic types of intercalated neurons: spiny and aspiny. Spiny neurons were the most abundant; their somata were small or medium size, round or elongated, and their dendritic trees were round or bipolar, depending on location. The aspiny neurons were on average slightly larger and had varicose dendrites with no spines. There were three non-overlapping neurochemical populations of IM neurons, in descending order of abundance: (1) Spiny neurons that were positive for the striatal associated dopamine- and cAMP-regulated phosphoprotein (DARPP-32+); (2) Aspiny neurons that expressed the calcium-binding protein calbindin (CB+); and (3) Aspiny neurons that expressed nitric oxide synthase (NOS+). The unique combinations of structural and neurochemical features of the three classes of IM neurons suggest different physiological properties and function. The three types of IM neurons were intermingled and likely interconnected in distinct ways, and were innervated by intrinsic neurons within the amygdala, or by external sources, in pathways that underlie fear conditioning and anxiety.
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Affiliation(s)
- Basilis Zikopoulos
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University, Boston, MA, United States; Graduate Program for Neuroscience, Boston University and School of Medicine, Boston, MA, United States.
| | - Yohan J John
- Neural Systems Laboratory, Department of Health Sciences, Boston University, Boston, MA, United States
| | | | - Jamie G Bunce
- Neural Systems Laboratory, Department of Health Sciences, Boston University, Boston, MA, United States
| | - Helen Barbas
- Graduate Program for Neuroscience, Boston University and School of Medicine, Boston, MA, United States; Neural Systems Laboratory, Department of Health Sciences, Boston University, Boston, MA, United States
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John YJ, Zikopoulos B, Bullock D, Barbas H. The Emotional Gatekeeper: A Computational Model of Attentional Selection and Suppression through the Pathway from the Amygdala to the Inhibitory Thalamic Reticular Nucleus. PLoS Comput Biol 2016; 12:e1004722. [PMID: 26828203 PMCID: PMC4734702 DOI: 10.1371/journal.pcbi.1004722] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 12/21/2015] [Indexed: 12/17/2022] Open
Abstract
In a complex environment that contains both opportunities and threats, it is important for an organism to flexibly direct attention based on current events and prior plans. The amygdala, the hub of the brain's emotional system, is involved in forming and signaling affective associations between stimuli and their consequences. The inhibitory thalamic reticular nucleus (TRN) is a hub of the attentional system that gates thalamo-cortical signaling. In the primate brain, a recently discovered pathway from the amygdala sends robust projections to TRN. Here we used computational modeling to demonstrate how the amygdala-TRN pathway, embedded in a wider neural circuit, can mediate selective attention guided by emotions. Our Emotional Gatekeeper model demonstrates how this circuit enables focused top-down, and flexible bottom-up, allocation of attention. The model suggests that the amygdala-TRN projection can serve as a unique mechanism for emotion-guided selection of signals sent to cortex for further processing. This inhibitory selection mechanism can mediate a powerful affective ‘framing’ effect that may lead to biased decision-making in highly charged emotional situations. The model also supports the idea that the amygdala can serve as a relevance detection system. Further, the model demonstrates how abnormal top-down drive and dysregulated local inhibition in the amygdala and in the cortex can contribute to the attentional symptoms that accompany several neuropsychiatric disorders. Emotional experiences grab our attention. Information about the emotional significance of events helps individuals weigh opportunities and dangers to guide goal-directed behavior, but may also lead to irrational decisions when the stakes are perceived to be high. Which neural circuits underlie these contrasting outcomes? A recently discovered pathway links the amygdala—a key center of the emotional system—with the inhibitory thalamic reticular nucleus (TRN) that filters information between the thalamus and cortex. We developed a neural network model—the Emotional Gatekeeper—that demonstrates how the newly discovered pathway from the amygdala to TRN highlights relevant information to help assess threats and opportunities. The model also shows how the amygdala-TRN pathway can lead normal individuals to discount neutral but useful information in highly charged emotional situations, and predicts that disruption of specific nodes in this circuit underlies distinct psychiatric disorders.
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Affiliation(s)
- Yohan J. John
- Neural Systems Laboratory, Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Basilis Zikopoulos
- Human Systems Neuroscience Laboratory, Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
- Graduate Program for Neuroscience, Boston University and School of Medicine, Boston, Massachusetts, United States of America
| | - Daniel Bullock
- Graduate Program for Neuroscience, Boston University and School of Medicine, Boston, Massachusetts, United States of America
- Department of Psychological and Brain Sciences, and the Center for Computational Neuroscience and Neural Technology, Boston University, Boston, Massachusetts, United States of America
| | - Helen Barbas
- Neural Systems Laboratory, Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
- Graduate Program for Neuroscience, Boston University and School of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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Pathways for Emotions: Specializations in the Amygdalar, Mediodorsal Thalamic, and Posterior Orbitofrontal Network. J Neurosci 2015; 35:11976-87. [PMID: 26311778 DOI: 10.1523/jneurosci.2157-15.2015] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED The primate amygdala projects to posterior orbitofrontal cortex (pOFC) directly and possibly indirectly through a pathway to the magnocellular mediodorsal thalamic nucleus (MDmc), which may convey signals about the significance of stimuli. However, because MDmc receives input from structures in addition to the amygdala and MDmc projects to areas in addition to pOFC, it is unknown whether amygdalar pathways in MDmc innervate pOFC-bound neurons. We addressed this issue using double- or triple-labeling approaches to identify pathways and key cellular and molecular features in rhesus monkeys. We found that amygdalar terminations innervated labeled neurons in MDmc that project to pOFC. Projection neurons in MDmc directed to pOFC included comparatively fewer "core" parvalbumin neurons that project focally to the middle cortical layers and more "matrix" calbindin neurons that project expansively to the upper cortical layers. In addition, a small and hitherto unknown pathway originated from MDmc calretinin neurons and projected to pOFC. Further, whereas projection neurons directed to MDmc and to pOFC were intermingled in the amygdala, none projected to both structures. Larger amygdalar neurons projected to MDmc and expressed the vesicular glutamate transporter 2 (VGLUT2), which is found in highly efficient "driver" pathways. In contrast, smaller amygdalar neurons directed to pOFC expressed VGLUT1 found in modulatory pathways. The indirect pathway from the amygdala to pOFC via MDmc may provide information about the emotional significance of events and, along with a parallel direct pathway, ensures transfer of signals to all layers of pOFC. SIGNIFICANCE STATEMENT The amygdala-the brain's center for emotions-is strongly linked with the orbital cortex, a region associated with social interactions. This study provides evidence that a robust pathway from the amygdala reaches neurons in the thalamus that link directly with the orbital cortex, forming a tight tripartite network. The dual pathways from the amygdala to the orbital cortex and to the thalamus are distinct by morphology, neurochemistry, and function. This tightly linked network suggests the presence of fool-proof avenues for emotions to influence high-order cortical areas associated with affective reasoning. Specific nodes of this tripartite network are disrupted in psychiatric diseases, divorcing areas that integrate emotions and thoughts for decisions and flexible behavior.
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Silverstein DN, Ingvar M. A multi-pathway hypothesis for human visual fear signaling. Front Syst Neurosci 2015; 9:101. [PMID: 26379513 PMCID: PMC4547041 DOI: 10.3389/fnsys.2015.00101] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 06/29/2015] [Indexed: 12/18/2022] Open
Abstract
A hypothesis is proposed for five visual fear signaling pathways in humans, based on an analysis of anatomical connectivity from primate studies and human functional connectvity and tractography from brain imaging studies. Earlier work has identified possible subcortical and cortical fear pathways known as the "low road" and "high road," which arrive at the amygdala independently. In addition to a subcortical pathway, we propose four cortical signaling pathways in humans along the visual ventral stream. All four of these traverse through the LGN to the visual cortex (VC) and branching off at the inferior temporal area, with one projection directly to the amygdala; another traversing the orbitofrontal cortex; and two others passing through the parietal and then prefrontal cortex, one excitatory pathway via the ventral-medial area and one regulatory pathway via the ventral-lateral area. These pathways have progressively longer propagation latencies and may have progressively evolved with brain development to take advantage of higher-level processing. Using the anatomical path lengths and latency estimates for each of these five pathways, predictions are made for the relative processing times at selective ROIs and arrival at the amygdala, based on the presentation of a fear-relevant visual stimulus. Partial verification of the temporal dynamics of this hypothesis might be accomplished using experimental MEG analysis. Possible experimental protocols are suggested.
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Affiliation(s)
- David N Silverstein
- PDC Center for High Performance Computing and Department of Computational Biology, KTH Royal Institute of Technology Stockholm, Sweden ; Stockholm Brain Institute, Karolinska Institutet Solna, Sweden
| | - Martin Ingvar
- Stockholm Brain Institute, Karolinska Institutet Solna, Sweden ; Department of Clinical Neuroscience, Karolinska Institutet Solna, Sweden
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32
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Barbas H. General Cortical and Special Prefrontal Connections: Principles from Structure to Function. Annu Rev Neurosci 2015; 38:269-89. [DOI: 10.1146/annurev-neuro-071714-033936] [Citation(s) in RCA: 237] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Helen Barbas
- Neural Systems Laboratory, Department of Health Sciences; Graduate Program in Neuroscience; School of Medicine; Boston University, Boston, Massachusetts 02215;
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Abstract
Aggression and violence represent a significant public health concern and a clinical challenge for the mental healthcare provider. A great deal has been revealed regarding the neurobiology of violence and aggression, and an integration of this body of knowledge will ultimately serve to advance clinical diagnostics and therapeutic interventions. We will review here the latest findings regarding the neurobiology of aggression and violence. First, we will introduce the construct of aggression, with a focus on issues related to its heterogeneity, as well as the importance of refining the aggression phenotype in order to reduce pathophysiologic variability. Next we will examine the neuroanatomy of aggression and violence, focusing on regional volumes, functional studies, and interregional connectivity. Significant emphasis will be on the amygdala, as well as amygdala-frontal circuitry. Then we will turn our attention to the neurochemistry and molecular genetics of aggression and violence, examining the extensive findings on the serotonergic system, as well as the growing literature on the dopaminergic and vasopressinergic systems. We will also address the contribution of steroid hormones, namely, cortisol and testosterone. Finally, we will summarize these findings with a focus on reconciling inconsistencies and potential clinical implications; and, then we will suggest areas of focus for future directions in the field.
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Abstract
Intuition suggests that perception follows sensation and therefore bodily feelings originate in the body. However, recent evidence goes against this logic: interoceptive experience may largely reflect limbic predictions about the expected state of the body that are constrained by ascending visceral sensations. In this Opinion article, we introduce the Embodied Predictive Interoception Coding model, which integrates an anatomical model of corticocortical connections with Bayesian active inference principles, to propose that agranular visceromotor cortices contribute to interoception by issuing interoceptive predictions. We then discuss how disruptions in interoceptive predictions could function as a common vulnerability for mental and physical illness.
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Affiliation(s)
- Lisa Feldman Barrett
- Northeastern University, Department of Psychology, Boston, Massachusetts 02115, USA; and the Massachusetts General Hospital, Department of Psychiatry and the Martinos Center for Biomedical Imaging, Charlestown, Massachusetts 02129, USA
| | - W Kyle Simmons
- Laureate Institute for Brain Research, Tulsa, Oklahoma 74133, USA; and the Faculty of Community Medicine, University of Tulsa, Tulsa, Oklahoma 74104, USA
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35
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Rutishauser U, Mamelak AN, Adolphs R. The primate amygdala in social perception - insights from electrophysiological recordings and stimulation. Trends Neurosci 2015; 38:295-306. [PMID: 25847686 DOI: 10.1016/j.tins.2015.03.001] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 03/05/2015] [Accepted: 03/05/2015] [Indexed: 11/19/2022]
Abstract
The role of the amygdala in emotion and social perception has been intensively investigated primarily through studies using functional magnetic resonance imaging (fMRI). Recently, this topic has been examined using single-unit recordings in both humans and monkeys, with a focus on face processing. The findings provide novel insights, including several surprises: amygdala neurons have very long response latencies, show highly nonlinear responses to whole faces, and can be exquisitely selective for very specific parts of faces such as the eyes. In humans, the responses of amygdala neurons correlate with internal states evoked by faces, rather than with their objective features. Current and future studies extend the investigations to psychiatric illnesses such as autism, in which atypical face processing is a hallmark of social dysfunction.
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Affiliation(s)
- Ueli Rutishauser
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA; Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Adam N Mamelak
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Ralph Adolphs
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
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Diversity of glutamatergic synaptic strength in lateral prefrontal versus primary visual cortices in the rhesus monkey. J Neurosci 2015; 35:112-27. [PMID: 25568107 DOI: 10.1523/jneurosci.3426-14.2015] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Understanding commonalities and differences in glutamatergic synaptic signaling is essential for understanding cortical functional diversity, especially in the highly complex primate brain. Previously, we have shown that spontaneous EPSCs differed markedly in layer 3 pyramidal neurons of two specialized cortical areas in the rhesus monkey, the high-order lateral prefrontal cortex (LPFC) and the primary visual cortex (V1). Here, we used patch-clamp recordings and confocal and electron microscopy to determine whether these distinct synaptic responses are due to differences in firing rates of presynaptic neurons and/or in the features of presynaptic or postsynaptic entities. As with spontaneous EPSCs, TTX-insensitive (action potential-independent) miniature EPSCs exhibited significantly higher frequency, greater amplitude, and slower kinetics in LPFC compared with V1 neurons. Consistent with these physiological differences, LPFC neurons possessed higher densities of spines, and the mean width of large spines was greater compared with those on V1 neurons. Axospinous synapses in layers 2-3 of LPFC had larger postsynaptic density surface areas and a higher proportion of large perforated synapses compared with V1. Axonal boutons in LPFC were also larger in volume and contained ∼ 1.6× more vesicles than did those in V1. Further, LPFC had a higher density of AMPA GluR2 receptor labeling than V1. The properties of spines and synaptic currents of individual layer 3 pyramidal neurons measured here were significantly correlated, consistent with the idea that significantly more frequent and larger synaptic currents are likely due to more numerous, larger, and more powerful synapses in LPFC compared with V1.
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Abstract
Social groups across species rapidly self-organize into hierarchies, where members vary in their level of power, influence, skill, or dominance. In this review, we explore the nature of social hierarchies and the traits associated with status in both humans and nonhuman primates, and how status varies across development in humans. Our review finds that we can rapidly identify social status based on a wide range of cues. Like monkeys, we tend to use certain cues, like physical strength, to make status judgments, although layered on top of these more primitive perceptual cues are sociocultural status cues like job titles and educational attainment. One's relative status has profound effects on attention, memory, and social interactions, as well as health and wellness. These effects can be particularly pernicious in children and adolescents. Developmental research on peer groups and social exclusion suggests teenagers may be particularly sensitive to social status information, but research focused specifically on status processing and associated brain areas is very limited. Recent evidence from neuroscience suggests that there may be an underlying neural network, including regions involved in executive, emotional, and reward processing, that is sensitive to status information. We conclude with questions for future research as well as stressing the need to expand social neuroscience research on status processing to adolescents.
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Affiliation(s)
- Jessica E Koski
- a Department of Psychology , Temple University , Philadelphia , PA 19122 , USA
| | - Hongling Xie
- a Department of Psychology , Temple University , Philadelphia , PA 19122 , USA
| | - Ingrid R Olson
- a Department of Psychology , Temple University , Philadelphia , PA 19122 , USA
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