1
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Xu Y, Lin Y, Yu M, Zhou K. The nucleus accumbens in reward and aversion processing: insights and implications. Front Behav Neurosci 2024; 18:1420028. [PMID: 39184934 PMCID: PMC11341389 DOI: 10.3389/fnbeh.2024.1420028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2024] [Accepted: 07/26/2024] [Indexed: 08/27/2024] Open
Abstract
The nucleus accumbens (NAc), a central component of the brain's reward circuitry, has been implicated in a wide range of behaviors and emotional states. Emerging evidence, primarily drawing from recent rodent studies, suggests that the function of the NAc in reward and aversion processing is multifaceted. Prolonged stress or drug use induces maladaptive neuronal function in the NAc circuitry, which results in pathological conditions. This review aims to provide comprehensive and up-to-date insights on the role of the NAc in motivated behavior regulation and highlights areas that demand further in-depth analysis. It synthesizes the latest findings on how distinct NAc neuronal populations and pathways contribute to the processing of opposite valences. The review examines how a range of neuromodulators, especially monoamines, influence the NAc's control over various motivational states. Furthermore, it delves into the complex underlying mechanisms of psychiatric disorders such as addiction and depression and evaluates prospective interventions to restore NAc functionality.
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Affiliation(s)
| | | | | | - Kuikui Zhou
- School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao, China
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2
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Edlow BL, Olchanyi M, Freeman HJ, Li J, Maffei C, Snider SB, Zöllei L, Iglesias JE, Augustinack J, Bodien YG, Haynes RL, Greve DN, Diamond BR, Stevens A, Giacino JT, Destrieux C, van der Kouwe A, Brown EN, Folkerth RD, Fischl B, Kinney HC. Multimodal MRI reveals brainstem connections that sustain wakefulness in human consciousness. Sci Transl Med 2024; 16:eadj4303. [PMID: 38691619 DOI: 10.1126/scitranslmed.adj4303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 04/10/2024] [Indexed: 05/03/2024]
Abstract
Consciousness is composed of arousal (i.e., wakefulness) and awareness. Substantial progress has been made in mapping the cortical networks that underlie awareness in the human brain, but knowledge about the subcortical networks that sustain arousal in humans is incomplete. Here, we aimed to map the connectivity of a proposed subcortical arousal network that sustains wakefulness in the human brain, analogous to the cortical default mode network (DMN) that has been shown to contribute to awareness. We integrated data from ex vivo diffusion magnetic resonance imaging (MRI) of three human brains, obtained at autopsy from neurologically normal individuals, with immunohistochemical staining of subcortical brain sections. We identified nodes of the proposed default ascending arousal network (dAAN) in the brainstem, hypothalamus, thalamus, and basal forebrain. Deterministic and probabilistic tractography analyses of the ex vivo diffusion MRI data revealed projection, association, and commissural pathways linking dAAN nodes with one another and with DMN nodes. Complementary analyses of in vivo 7-tesla resting-state functional MRI data from the Human Connectome Project identified the dopaminergic ventral tegmental area in the midbrain as a widely connected hub node at the nexus of the subcortical arousal and cortical awareness networks. Our network-based autopsy methods and connectivity data provide a putative neuroanatomic architecture for the integration of arousal and awareness in human consciousness.
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Affiliation(s)
- Brian L Edlow
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Mark Olchanyi
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Holly J Freeman
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Jian Li
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Chiara Maffei
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Samuel B Snider
- Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Lilla Zöllei
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - J Eugenio Iglesias
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Jean Augustinack
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Yelena G Bodien
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Robin L Haynes
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Douglas N Greve
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Bram R Diamond
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Allison Stevens
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Joseph T Giacino
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Christophe Destrieux
- UMR 1253, iBrain, Université de Tours, Inserm, 10 Boulevard Tonnellé, 37032, Tours, France
- CHRU de Tours, 2 Boulevard Tonnellé, Tours, France
| | - Andre van der Kouwe
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Emery N Brown
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | | | - Bruce Fischl
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Hannah C Kinney
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA 02115, USA
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3
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Chaves T, Török B, Fazekas CL, Correia P, Sipos E, Várkonyi D, Tóth ZE, Dóra F, Dobolyi Á, Zelena D. The Dopaminergic Cells in the Median Raphe Region Regulate Social Behavior in Male Mice. Int J Mol Sci 2024; 25:4315. [PMID: 38673899 PMCID: PMC11050709 DOI: 10.3390/ijms25084315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 04/08/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024] Open
Abstract
According to previous studies, the median raphe region (MRR) is known to contribute significantly to social behavior. Besides serotonin, there have also been reports of a small population of dopaminergic neurons in this region. Dopamine is linked to reward and locomotion, but very little is known about its role in the MRR. To address that, we first confirmed the presence of dopaminergic cells in the MRR of mice (immunohistochemistry, RT-PCR), and then also in humans (RT-PCR) using healthy donor samples to prove translational relevance. Next, we used chemogenetic technology in mice containing the Cre enzyme under the promoter of the dopamine transporter. With the help of an adeno-associated virus, designer receptors exclusively activated by designer drugs (DREADDs) were expressed in the dopaminergic cells of the MRR to manipulate their activity. Four weeks later, we performed an extensive behavioral characterization 30 min after the injection of the artificial ligand (Clozapine-N-Oxide). Stimulation of the dopaminergic cells in the MRR decreased social interest without influencing aggression and with an increase in social discrimination. Additionally, inhibition of the same cells increased the friendly social behavior during social interaction test. No behavioral changes were detected in anxiety, memory or locomotion. All in all, dopaminergic cells were present in both the mouse and human samples from the MRR, and the manipulation of the dopaminergic neurons in the MRR elicited a specific social response.
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Affiliation(s)
- Tiago Chaves
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (T.C.); (B.T.); (C.L.F.); (P.C.); (D.V.)
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
- János Szentágothai School of Neurosciences, Semmelweis University, H1085 Budapest, Hungary
| | - Bibiána Török
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (T.C.); (B.T.); (C.L.F.); (P.C.); (D.V.)
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
- János Szentágothai School of Neurosciences, Semmelweis University, H1085 Budapest, Hungary
| | - Csilla Lea Fazekas
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (T.C.); (B.T.); (C.L.F.); (P.C.); (D.V.)
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
- János Szentágothai School of Neurosciences, Semmelweis University, H1085 Budapest, Hungary
| | - Pedro Correia
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (T.C.); (B.T.); (C.L.F.); (P.C.); (D.V.)
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
- János Szentágothai School of Neurosciences, Semmelweis University, H1085 Budapest, Hungary
| | - Eszter Sipos
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
| | - Dorottya Várkonyi
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (T.C.); (B.T.); (C.L.F.); (P.C.); (D.V.)
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
| | - Zsuzsanna E. Tóth
- Laboratory of Neuroendocrinology and in Situ Hybridization, Department of Anatomy, Histology and Embryology, Semmelweis University, H1094 Budapest, Hungary;
| | - Fanni Dóra
- Human Brain Tissue Bank, Laboratory of Neuromorphology, Department of Anatomy, Histology and Embryology, Semmelweis University, H1094 Budapest, Hungary;
| | - Árpád Dobolyi
- Laboratory of Molecular and Systems Neurobiology, Department of Physiology and Neurobiology, Eötvös Loránd University, H1117 Budapest, Hungary;
| | - Dóra Zelena
- Institute of Physiology, Medical School, Centre for Neuroscience, Szentágothai Research Centre, University of Pécs, H7624 Pécs, Hungary; (T.C.); (B.T.); (C.L.F.); (P.C.); (D.V.)
- Laboratory of Behavioral and Stress Studies, Institute of Experimental Medicine, H1083 Budapest, Hungary;
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4
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Kumar VJ, Scheffler K, Grodd W. The structural connectivity mapping of the intralaminar thalamic nuclei. Sci Rep 2023; 13:11938. [PMID: 37488187 PMCID: PMC10366221 DOI: 10.1038/s41598-023-38967-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/18/2023] [Indexed: 07/26/2023] Open
Abstract
The intralaminar nuclei of the thalamus play a pivotal role in awareness, conscious experience, arousal, sleep, vigilance, as well as in cognitive, sensory, and sexual processing. Nonetheless, in humans, little is known about the direct involvement of these nuclei in such multifaceted functions and their structural connections in the brain. Thus, examining the versatility of structural connectivity of the intralaminar nuclei with the rest of the brain seems reasonable. Herein, we attempt to show the direct structural connectivity of the intralaminar nuclei to diencephalic, mesencephalic, and cortical areas using probabilistic tracking of the diffusion data from the human connectome project. The intralaminar nuclei fiber distributions span a wide range of subcortical and cortical areas. Moreover, the central medial and parafascicular nucleus reveal similar connectivity to the temporal, visual, and frontal cortices with only slight variability. The central lateral nucleus displays a refined projection to the superior colliculus and fornix. The centromedian nucleus seems to be an essential component of the subcortical somatosensory system, as it mainly displays connectivity via the medial and superior cerebellar peduncle to the brainstem and the cerebellar lobules. The subparafascicular nucleus projects to the somatosensory processing areas. It is interesting to note that all intralaminar nuclei have connections to the brainstem. In brief, the structural connectivity of the intralaminar nuclei aligns with the structural core of various functional demands for arousal, emotion, cognition, sensory, vision, and motor processing. This study sheds light on our understanding of the structural connectivity of the intralaminar nuclei with cortical and subcortical structures, which is of great interest to a broader audience in clinical and neuroscience research.
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Affiliation(s)
| | - Klaus Scheffler
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- Department of Biomedical Magnetic Resonance, University Clinic Tübingen, Tübingen, Germany
| | - Wolfgang Grodd
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
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5
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Edlow BL, Olchanyi M, Freeman HJ, Li J, Maffei C, Snider SB, Zöllei L, Iglesias JE, Augustinack J, Bodien YG, Haynes RL, Greve DN, Diamond BR, Stevens A, Giacino JT, Destrieux C, van der Kouwe A, Brown EN, Folkerth RD, Fischl B, Kinney HC. Sustaining wakefulness: Brainstem connectivity in human consciousness. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.13.548265. [PMID: 37502983 PMCID: PMC10369992 DOI: 10.1101/2023.07.13.548265] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Consciousness is comprised of arousal (i.e., wakefulness) and awareness. Substantial progress has been made in mapping the cortical networks that modulate awareness in the human brain, but knowledge about the subcortical networks that sustain arousal is lacking. We integrated data from ex vivo diffusion MRI, immunohistochemistry, and in vivo 7 Tesla functional MRI to map the connectivity of a subcortical arousal network that we postulate sustains wakefulness in the resting, conscious human brain, analogous to the cortical default mode network (DMN) that is believed to sustain self-awareness. We identified nodes of the proposed default ascending arousal network (dAAN) in the brainstem, hypothalamus, thalamus, and basal forebrain by correlating ex vivo diffusion MRI with immunohistochemistry in three human brain specimens from neurologically normal individuals scanned at 600-750 μm resolution. We performed deterministic and probabilistic tractography analyses of the diffusion MRI data to map dAAN intra-network connections and dAAN-DMN internetwork connections. Using a newly developed network-based autopsy of the human brain that integrates ex vivo MRI and histopathology, we identified projection, association, and commissural pathways linking dAAN nodes with one another and with cortical DMN nodes, providing a structural architecture for the integration of arousal and awareness in human consciousness. We release the ex vivo diffusion MRI data, corresponding immunohistochemistry data, network-based autopsy methods, and a new brainstem dAAN atlas to support efforts to map the connectivity of human consciousness.
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Affiliation(s)
- Brian L. Edlow
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Mark Olchanyi
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Holly J. Freeman
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Jian Li
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Chiara Maffei
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Samuel B. Snider
- Department of Neurology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Lilla Zöllei
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - J. Eugenio Iglesias
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Jean Augustinack
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Yelena G. Bodien
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Harvard Medical School, Charlestown, MA 02129 USA
| | - Robin L. Haynes
- Department of Pathology, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Douglas N. Greve
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Bram R. Diamond
- Center for Neurotechnology and Neurorecovery, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Allison Stevens
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Joseph T. Giacino
- Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital and Harvard Medical School, Charlestown, MA 02129 USA
| | - Christophe Destrieux
- UMR 1253, iBrain, Université de Tours, Inserm, 10 Boulevard Tonnellé, 37032, Tours, France
- CHRU de Tours, 2 Boulevard Tonnellé, Tours, France
| | - Andre van der Kouwe
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
| | - Emery N. Brown
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Bruce Fischl
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown MA 02129, USA
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hannah C. Kinney
- Department of Pathology, Boston Children’s Hospital and Harvard Medical School, Boston, MA 02115, USA
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Vertes RP, Linley SB, Rojas AKP. Structural and functional organization of the midline and intralaminar nuclei of the thalamus. Front Behav Neurosci 2022; 16:964644. [PMID: 36082310 PMCID: PMC9445584 DOI: 10.3389/fnbeh.2022.964644] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/07/2022] [Indexed: 12/03/2022] Open
Abstract
The midline and intralaminar nuclei of the thalamus form a major part of the "limbic thalamus;" that is, thalamic structures anatomically and functionally linked with the limbic forebrain. The midline nuclei consist of the paraventricular (PV) and paratenial nuclei, dorsally and the rhomboid and nucleus reuniens (RE), ventrally. The rostral intralaminar nuclei (ILt) consist of the central medial (CM), paracentral (PC) and central lateral (CL) nuclei. We presently concentrate on RE, PV, CM and CL nuclei of the thalamus. The nucleus reuniens receives a diverse array of input from limbic-related sites, and predominantly projects to the hippocampus and to "limbic" cortices. The RE participates in various cognitive functions including spatial working memory, executive functions (attention, behavioral flexibility) and affect/fear behavior. The PV receives significant limbic-related afferents, particularly the hypothalamus, and mainly distributes to "affective" structures of the forebrain including the bed nucleus of stria terminalis, nucleus accumbens and the amygdala. Accordingly, PV serves a critical role in "motivated behaviors" such as arousal, feeding/consummatory behavior and drug addiction. The rostral ILt receives both limbic and sensorimotor-related input and distributes widely over limbic and motor regions of the frontal cortex-and throughout the dorsal striatum. The intralaminar thalamus is critical for maintaining consciousness and directly participates in various sensorimotor functions (visuospatial or reaction time tasks) and cognitive tasks involving striatal-cortical interactions. As discussed herein, while each of the midline and intralaminar nuclei are anatomically and functionally distinct, they collectively serve a vital role in several affective, cognitive and executive behaviors - as major components of a brainstem-diencephalic-thalamocortical circuitry.
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Affiliation(s)
- Robert P. Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, United States
- Department of Psychology, Florida Atlantic University, Boca Raton, FL, United States
| | - Stephanie B. Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, United States
- Department of Psychology, Florida Atlantic University, Boca Raton, FL, United States
- Department of Psychological Science, University of North Georgia, Dahlonega, GA, United States
| | - Amanda K. P. Rojas
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL, United States
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Bagnato S. The role of plasticity in the recovery of consciousness. HANDBOOK OF CLINICAL NEUROLOGY 2022; 184:375-395. [PMID: 35034750 DOI: 10.1016/b978-0-12-819410-2.00020-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Disorders of consciousness (DOCs), i.e., coma, vegetative state, and minimally conscious state are the consequences of a severe brain injury that disrupts the brain ability to generate consciousness. Recovery from DOCs requires functional and structural changes in the brain. The sites where these plastic changes take place vary according to the pathophysiology of the DOC. The ascending reticular activating system of the brainstem and its complex connections with the thalamus and cortex are involved in the pathophysiology of coma. Subcortical structures, such as the striatum and globus pallidus, together with thalamocortical and corticothalamic projections, the basal forebrain, and several networks among different cortical areas are probably involved in vegetative and minimally conscious states. Some mechanisms of plasticity that allegedly operate in each of these sites to promote recovery of consciousness will be discussed in this chapter. While some mechanisms of plasticity work at a local level, others produce functional changes in complex neuronal networks, for example by entraining neuronal oscillations. The specific mechanisms of brain plasticity represent potential targets for future treatments aiming to restore consciousness in patients with severe DOCs.
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Affiliation(s)
- Sergio Bagnato
- Unit of Neurophysiology and Unit for Severe Acquired Brain Injuries, Rehabilitation Department, Giuseppe Giglio Foundation, Cefalù (PA), Italy.
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8
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Staszelis A, Kowalczyk T. The role of the posterior hypothalamic area
in the generation of theta rhythm. POSTEP HIG MED DOSW 2021. [DOI: 10.5604/01.3001.0014.9333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Theta rhythm is one of the best synchronized patterns of the oscillatory activity recorded in
the mammalian brain. In humans, this rhythm is associated with REM sleep, spatial navigation,
memory functions, analytical and language processes. On the other hand, it can be treated as
a non-specific marker of such pathological states of the central nervous system as Alzheimer’s
disease or epilepsy. The hippocampal formation is the key structure involved in the generation
of this bioelectric phenomenon, both in humans and rodents (the most commonly studied laboratory
animals). Theta rhythm appearance in the hippocampus is dependent on the interaction
of multiple different structures of the nervous system. One of them is the posterior hypothalamic
area (PHa), which constitutes a crucial part of the neuronal system modulating the ability
of the hippocampal formation to generate theta rhythm. Although the research results encompassed
in this paper emphasize the essential role of the PHa as a modulator of the hippocampal
theta rhythm, it was the authors’ intent to indicate that this area is also capable of generating
local rhythmical theta oscillations, independently of the influence of other brain structures.
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Affiliation(s)
- Agata Staszelis
- Katedra Neurobiologii, Wydział Biologii i Ochrony Środowiska, Uniwersytet Łódzki, Łódź
| | - Tomasz Kowalczyk
- Katedra Neurobiologii, Wydział Biologii i Ochrony Środowiska, Uniwersytet Łódzki, Łódź
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9
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Roman E, Weininger J, Lim B, Roman M, Barry D, Tierney P, O'Hanlon E, Levins K, O'Keane V, Roddy D. Untangling the dorsal diencephalic conduction system: a review of structure and function of the stria medullaris, habenula and fasciculus retroflexus. Brain Struct Funct 2020; 225:1437-1458. [PMID: 32367265 DOI: 10.1007/s00429-020-02069-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2019] [Accepted: 04/11/2020] [Indexed: 12/23/2022]
Abstract
The often-overlooked dorsal diencephalic conduction system (DDCS) is a highly conserved pathway linking the basal forebrain and the monoaminergic brainstem. It consists of three key structures; the stria medullaris, the habenula and the fasciculus retroflexus. The first component of the DDCS, the stria medullaris, is a discrete bilateral tract composed of fibers from the basal forebrain that terminate in the triangular eminence of the stalk of the pineal gland, known as the habenula. The habenula acts as a relay hub where incoming signals from the stria medullaris are processed and subsequently relayed to the midbrain and hindbrain monoaminergic nuclei through the fasciculus retroflexus. As a result of its wide-ranging connections, the DDCS has recently been implicated in a wide range of behaviors related to reward processing, aversion and motivation. As such, an understanding of the structure and connections of the DDCS may help illuminate the pathophysiology of neuropsychiatric disorders such as depression, addiction and pain. This is the first review of all three components of the DDCS, the stria medullaris, the habenula and the fasciculus retroflexus, with particular focus on their anatomy, function and development.
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Affiliation(s)
- Elena Roman
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.,Department of Psychiatry, Education and Research Centre , Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Joshua Weininger
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Basil Lim
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.,Department of Game Design, Technological University Dublin, Dublin 2, Ireland
| | - Marin Roman
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Denis Barry
- Anatomy Department, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Paul Tierney
- Anatomy Department, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
| | - Erik O'Hanlon
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.,Department of Psychiatry, Education and Research Centre , Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Kirk Levins
- Department of Anaesthetics, Intensive Care and Pain Medicine, St. Vincent's University Hospital, Dublin 4, Ireland
| | - Veronica O'Keane
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Darren Roddy
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland.
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10
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Moriya S, Yamashita A, Masukawa D, Kambe Y, Sakaguchi J, Setoyama H, Yamanaka A, Kuwaki T. Involvement of supralemniscal nucleus (B9) 5-HT neuronal system in nociceptive processing: a fiber photometry study. Mol Brain 2020; 13:14. [PMID: 32005128 PMCID: PMC6993514 DOI: 10.1186/s13041-020-0553-1] [Citation(s) in RCA: 4] [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: 10/03/2019] [Accepted: 01/19/2020] [Indexed: 12/15/2022] Open
Abstract
Nociception is important perception that has harmful influence on daily life of humans. As to main pain management system, some descending pathways are called descending antinociceptive systems (DAS). As main pathways of DAS, it is well known that dorsal raphe (B6/B7) - rostral ventromedial medulla (B3) - spinal dorsal horn includes serotonergic system. However, possible role of supralemniscal (B9) serotonin (5-HT) cell group in pain management is still open question. In this study, we measured activities of B9 5-HT neuronal cell bodies and B9 5-HT neuron-derived axons located in the locus coeruleus (LC) and ventral tegmental area (VTA), which are also main players of pain management, using fiber photometry system. We introduced the G-CaMP6 in B9 5-HT neurons using transgenic mice carrying a tetracycline-controlled transactivator transgene (tTA) under the control of a tryptophan hydroxylase-2 (TPH2) promoter and site-specific injection of adeno associated virus (AAV-TetO(3G)-G-CaMP6). After confirmation of specific expression of G-CaMP6 in the target population, G-CaMP6 fluorescence intensity in B9 group and LC/VTA groups was measured in awake mice exposed to acute tail pinch and heat stimuli. G-CaMP6 fluorescence intensity rapidly increased by both stimuli in all groups, but not significantly reacted by nonnociceptive control stimuli. The present results clearly indicate that acute nociceptive stimuli cause a rapid increase in the activities of B9-LC/B9-VTA 5-HTergic pathways, suggesting that B9 5-HT neurons play important roles in nociceptive processing.
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Affiliation(s)
- Shunpei Moriya
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, 890-8544 Japan
| | - Akira Yamashita
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, 890-8544 Japan
| | - Daiki Masukawa
- Department of Molecular Pharmacology and Neurobiology, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004 Japan
| | - Yuki Kambe
- Department of Pharmacology, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, 890-8544 Japan
| | - Junichi Sakaguchi
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, 890-8544 Japan
| | - Honami Setoyama
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, 890-8544 Japan
| | - Akihiro Yamanaka
- Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601 Japan
| | - Tomoyuki Kuwaki
- Department of Physiology, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima, 890-8544 Japan
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11
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Metzger M, Souza R, Lima LB, Bueno D, Gonçalves L, Sego C, Donato J, Shammah-Lagnado SJ. Habenular connections with the dopaminergic and serotonergic system and their role in stress-related psychiatric disorders. Eur J Neurosci 2019; 53:65-88. [PMID: 31833616 DOI: 10.1111/ejn.14647] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/28/2019] [Accepted: 12/09/2019] [Indexed: 12/19/2022]
Abstract
The habenula (Hb) is a phylogenetically old epithalamic structure differentiated into two nuclear complexes, the medial (MHb) and lateral habenula (LHb). After decades of search for a great unifying function, interest in the Hb resurged when it was demonstrated that LHb plays a major role in the encoding of aversive stimuli ranging from noxious stimuli to the loss of predicted rewards. Consistent with a role as an anti-reward center, aberrant LHb activity has now been identified as a key factor in the pathogenesis of major depressive disorder. Moreover, both MHb and LHb emerged as new players in the reward circuitry by primarily mediating the aversive properties of distinct drugs of abuse. Anatomically, the Hb serves as a bridge that links basal forebrain structures with monoaminergic nuclei in the mid- and hindbrain. So far, research on Hb has focused on the role of the LHb in regulating midbrain dopamine release. However, LHb/MHb are also interconnected with the dorsal (DR) and median (MnR) raphe nucleus. Hence, it is conceivable that some of the habenular functions are at least partly mediated by the complex network that links MHb/LHb with pontomesencephalic monoaminergic nuclei. Here, we summarize research about the topography and transmitter phenotype of the reciprocal connections between the LHb and ventral tegmental area-nigra complex, as well as those between the LHb and DR/MnR. Indirect MHb outputs via interpeduncular nucleus to state-setting neuromodulatory networks will also be commented. Finally, we discuss the role of specific LHb-VTA and LHb/MHb-raphe circuits in anxiety and depression.
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Affiliation(s)
- Martin Metzger
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Rudieri Souza
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Leandro B Lima
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Debora Bueno
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Luciano Gonçalves
- Department of Human Anatomy, Federal University of the Triângulo Mineiro, Uberaba, Brazil
| | - Chemutai Sego
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Jose Donato
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Sara J Shammah-Lagnado
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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12
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Chauvière L. Update on temporal lobe‐dependent information processing, in health and disease. Eur J Neurosci 2019; 51:2159-2204. [DOI: 10.1111/ejn.14594] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/06/2019] [Accepted: 09/27/2019] [Indexed: 01/29/2023]
Affiliation(s)
- Laëtitia Chauvière
- INSERM U1266 Institut de Psychiatrie et de Neurosciences de Paris (IPNP) Paris France
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13
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Baker PM, Rao Y, Rivera ZMG, Garcia EM, Mizumori SJY. Selective Functional Interaction Between the Lateral Habenula and Hippocampus During Different Tests of Response Flexibility. Front Mol Neurosci 2019; 12:245. [PMID: 31680854 PMCID: PMC6803433 DOI: 10.3389/fnmol.2019.00245] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 09/24/2019] [Indexed: 12/16/2022] Open
Abstract
The lateral habenula (LHb) has been shown to play critical roles in a variety of appetitive tasks (e.g., spatial memory and object recognition) that require animals to flexibly respond to changing task conditions. These types of tasks are known to be dependent on hippocampus (HPC) and/or medial prefrontal cortex (mPFC), suggesting that the LHb contributes to the limbic memory circuit. Here we provide new evidence that the LHb and HPC play distinct but complimentary roles in tasks that require flexible responding to changing task conditions. Experiment 1 tested whether the LHb is needed for the performance of a HPC-dependent maze-based spatial delayed alternation task. The importance of interactions between the LHb and HPC to accomplish the same spatial delayed alternation task was tested in Experiment 2 where the LHb and HPC were disconnected both ipsilaterally and contralaterally. Experiment 3 tested LHb's involvement in a standard behavioral economic task that requires flexible responding (maze-based delayed discounting), a task previously shown to rely on HPC. Results of Experiment 1, revealed that LHb inactivation impairs spatial delayed alternation during asymptotic performance but not during initial learning. Importantly, working memory did not appear to be affected as performance remained above chance levels both during initial learning and asymptotic testing. Experiment 2 showed that ipsilateral and contralateral disconnection of the LHb and HPC led to impaired performance on the spatial delayed alternation task. Impairments were not observed after unilateral inactivation of only one structure. Results of Experiment 3 were similar to our previous report of the effects of HPC inactivation: LHb inactivation impaired delayed discounting. All effects could not be accounted for by changes in reward magnitude discrimination, reward location per se, or sex of the animal. These findings, combined with other recent publications confirms and extends our working hypothesis that the LHb enables adaptive and flexible responding, particularly when established rules must be flexibly applied on a trial by trial basis. Since there are no known direct anatomical connections between LHb and HPC, future research is needed to understand how these structures communicate to enable flexible and rapid responding.
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Affiliation(s)
- Phillip M Baker
- Department of Psychology, Seattle Pacific University, Seattle, WA, United States
| | - Yingxue Rao
- Department of Psychology, University of Washington, Seattle, WA, United States
| | - Zeena M G Rivera
- Department of Psychology, University of Washington, Seattle, WA, United States
| | - Esteli M Garcia
- Department of Psychology, University of Washington, Seattle, WA, United States
| | - Sheri J Y Mizumori
- Department of Psychology, University of Washington, Seattle, WA, United States.,Program in Neuroscience, University of Washington, Seattle, WA, United States
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14
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Salay LD, Ishiko N, Huberman AD. A midline thalamic circuit determines reactions to visual threat. Nature 2018; 557:183-189. [DOI: 10.1038/s41586-018-0078-2] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 03/23/2018] [Indexed: 01/27/2023]
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15
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Aitken P, Zheng Y, Smith PF. The modulation of hippocampal theta rhythm by the vestibular system. J Neurophysiol 2018; 119:548-562. [DOI: 10.1152/jn.00548.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The vestibular system is a sensory system that has evolved over millions of years to detect acceleration of the head, both rotational and translational, in three dimensions. One of its most important functions is to stabilize gaze during unexpected head movement; however, it is also important in the control of posture and autonomic reflexes. Theta rhythm is a 3- to 12-Hz oscillating EEG signal that is intimately linked to self-motion and is also known to be important in learning and memory. Many studies over the last two decades have shown that selective activation of the vestibular system, using either natural rotational or translational stimulation, or electrical stimulation of the peripheral vestibular system, can induce and modulate theta activity. Furthermore, inactivation of the vestibular system has been shown to significantly reduce theta in freely moving animals, which may be linked to its impairment of place cell function as well as spatial learning and memory. The pathways through which vestibular information modulate theta rhythm remain debatable. However, vestibular responses have been found in the pedunculopontine tegmental nucleus (PPTg) and activation of the vestibular system causes an increase in acetylcholine release into the hippocampus, probably from the medial septum. Therefore, a pathway from the vestibular nucleus complex and/or cerebellum to the PPTg, supramammillary nucleus, posterior hypothalamic nucleus, and septum to the hippocampus is likely. The modulation of theta by the vestibular system may have implications for vestibular effects on cognitive function and the contribution of vestibular impairment to the risk of dementia.
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Affiliation(s)
- Phillip Aitken
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Yiwen Zheng
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand Centre of Research Excellence
- Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
| | - Paul F. Smith
- Department of Pharmacology and Toxicology, School of Biomedical Sciences, and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
- Brain Research New Zealand Centre of Research Excellence
- Eisdell Moore Centre for Hearing and Balance Research, University of Auckland, Auckland, New Zealand
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16
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Tsanov M. Differential and complementary roles of medial and lateral septum in the orchestration of limbic oscillations and signal integration. Eur J Neurosci 2017; 48:2783-2794. [DOI: 10.1111/ejn.13746] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/06/2017] [Accepted: 10/09/2017] [Indexed: 12/14/2022]
Affiliation(s)
- Marian Tsanov
- Trinity College Institute of Neuroscience; Trinity College Dublin; Dublin 2 Ireland
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17
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Zahm DS, Root DH. Review of the cytology and connections of the lateral habenula, an avatar of adaptive behaving. Pharmacol Biochem Behav 2017; 162:3-21. [PMID: 28647565 PMCID: PMC5659881 DOI: 10.1016/j.pbb.2017.06.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 05/02/2017] [Accepted: 06/13/2017] [Indexed: 12/21/2022]
Abstract
The cytology and connections of the lateral habenula (LHb) are reviewed. The habenula is first introduced, after which the cytology of the LHb is discussed mainly with reference to cell types, general topography and descriptions of subnuclei. An overview of LHb afferent connections is given followed by some details about the projections to LHb from a number of structures. An overview of lateral habenula efferent connections is given followed by some details about the projections from LHb to a number of structures. In considering the afferent and efferent connections of the LHb some attention is given to the relative validity of regarding it as a bi-partite structure featuring 'limbic' and 'pallidal' parts. The paper ends with some concluding remarks about the relative place of the LHb in adaptive behaving.
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Affiliation(s)
- Daniel S Zahm
- Department of Pharmacology and Physiology, Saint Louis University School of Medicine, 1402 S. Grand Blvd., Saint Louis, MO 63104, United States.
| | - David H Root
- Department of Psychology and Neuroscience, University of Colorado Boulder, Boulder, CO 80309, United States.
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18
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Nuclear derivatives and axonal projections originating from rhombomere 4 in the mouse hindbrain. Brain Struct Funct 2017; 222:3509-3542. [PMID: 28470551 PMCID: PMC5676809 DOI: 10.1007/s00429-017-1416-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 03/27/2017] [Indexed: 01/13/2023]
Abstract
The r4-derived territory is located in the pontine region of the brainstem, forming a wedge-shaped slice that broadens from the choroidal roof to the ventral midline. R4-derived neuronal populations migrate radially inside and tangentially outside this rhombomere, forming nuclei of the sensorimotor auditory, vestibular, trigeminal and reticular systems. R4-derived fibre tracts contribute to the lateral lemniscus, the trigeminothalamic tracts, the medial tegmental tract and the medial forebrain bundle, which variously project to the midbrain, thalamus, hypothalamus and telencephalon. Other tracts such as the trigeminocerebellar and vestibulocerebellar tracts reach the cerebellum, while the medial and lateral vestibulospinal tracts, and the reticulospinal and trigeminal oro-spinal tracts extend into the spinal cord. Many r4-derived fibres are crossed; they decussate to the contralateral side traversing the midline through the cerebellar, collicular and intercollicular commissures, as well as the supraoptic decussation. Moreover, some fibres enter into the posterior and anterior commissures and some terminals reach the septum. Overall, this study provides an overview of all r4 neuronal populations and axonal tracts from their embryonic origin to the adult final location and target.
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19
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Effects of bilateral vestibular deafferentation in rat on hippocampal theta response to somatosensory stimulation, acetylcholine release, and cholinergic neurons in the pedunculopontine tegmental nucleus. Brain Struct Funct 2017; 222:3319-3332. [PMID: 28349227 DOI: 10.1007/s00429-017-1407-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 03/14/2017] [Indexed: 12/18/2022]
Abstract
Vestibular dysfunction has been shown to cause spatial memory impairment. Neurophysiological studies indicate that bilateral vestibular loss (BVL), in particular, is associated with an impairment of the response of hippocampal place cells and theta rhythm. However, the specific neural pathways through which vestibular information reaches the hippocampus are yet to be fully elucidated. The aim of the present study was to further investigate the hypothesised 'theta-generating pathway' from the brainstem vestibular nucleus to the hippocampus. BVL, and in some cases, unilateral vestibular loss (UVL), induced by intratympanic sodium arsanilate injections in rats, were used to investigate the effects of vestibular loss on somatosensory-induced type 2 theta rhythm, acetylcholine (ACh) release in the hippocampus, and the number of cholinergic neurons in the pedunculopontine tegmental nucleus (PPTg), an important part of the theta-generating pathway. Under urethane anaesthesia, BVL was found to cause a significant increase in the maximum power of the type 2 theta (3-6 Hz) frequency band compared to UVL and sham animals. Rats with BVL generally exhibited a lower basal level of ACh release than sham rats; however, this difference was not statistically significant. The PPTg of BVL rats exhibited significantly more choline-acetyltransferase (ChAT)-positive neurons than that of sham animals, as did the contralateral PPTg of UVL animals; however, the number of ChAT-positive neurons on the ipsilateral side of UVL animals was not significantly different from sham animals. The results of these studies indicate that parts of the theta-generating pathway undergo a significant reorganisation following vestibular loss, which suggests that this pathway is important for the interaction between the vestibular system and the hippocampus.
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20
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Kumar JR, Rajkumar R, Jayakody T, Marwari S, Hong JM, Ma S, Gundlach AL, Lai MKP, Dawe GS. Relaxin' the brain: a case for targeting the nucleus incertus network and relaxin-3/RXFP3 system in neuropsychiatric disorders. Br J Pharmacol 2016; 174:1061-1076. [PMID: 27597467 PMCID: PMC5406295 DOI: 10.1111/bph.13564] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 07/15/2016] [Indexed: 12/14/2022] Open
Abstract
Relaxin‐3 has been proposed to modulate emotional–behavioural functions such as arousal and behavioural activation, appetite regulation, stress responses, anxiety, memory, sleep and circadian rhythm. The nucleus incertus (NI), in the midline tegmentum close to the fourth ventricle, projects widely throughout the brain and is the primary site of relaxin‐3 neurons. Over recent years, a number of preclinical studies have explored the function of the NI and relaxin‐3 signalling, including reports of mRNA or peptide expression changes in the NI in response to behavioural or pharmacological manipulations, effects of lesions or electrical or pharmacological manipulations of the NI, effects of central microinfusions of relaxin‐3 or related agonist or antagonist ligands on physiology and behaviour, and the impact of relaxin‐3 gene deletion or knockdown. Although these individual studies reveal facets of the likely functional relevance of the NI and relaxin‐3 systems for human physiology and behaviour, the differences observed in responses between species (e.g. rat vs. mouse), the clearly identified heterogeneity of NI neurons and procedural differences between laboratories are some of the factors that have prevented a precise understanding of their function. This review aims to draw attention to the current preclinical evidence available that suggests the relevance of the NI/relaxin‐3 system to the pathology and/or symptoms of certain neuropsychiatric disorders and to provide cognizant directions for future research to effectively and efficiently uncover its therapeutic potential. Linked Articles This article is part of a themed section on Recent Progress in the Understanding of Relaxin Family Peptides and their Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.10/issuetoc
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Affiliation(s)
- Jigna Rajesh Kumar
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore.,Singapore Institute for Neurotechnology (SINAPSE), Singapore.,NUS Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, Singapore
| | - Ramamoorthy Rajkumar
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore.,Singapore Institute for Neurotechnology (SINAPSE), Singapore
| | - Tharindunee Jayakody
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore.,Singapore Institute for Neurotechnology (SINAPSE), Singapore
| | - Subhi Marwari
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore.,Singapore Institute for Neurotechnology (SINAPSE), Singapore
| | - Jia Mei Hong
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore.,Singapore Institute for Neurotechnology (SINAPSE), Singapore.,NUS Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, Singapore
| | - Sherie Ma
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia.,Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Andrew L Gundlach
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia.,Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.,Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - Mitchell K P Lai
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Gavin S Dawe
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore.,Singapore Institute for Neurotechnology (SINAPSE), Singapore.,NUS Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, Singapore
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21
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Bocian R, Kłos-Wojtczak P, Caban B, Kowalczyk T, Kaźmierska P, Konopacki J. Cell discharge correlates of posterior hypothalamic theta rhythm recorded in anesthetized rats and brain slices. Hippocampus 2016; 26:1354-69. [DOI: 10.1002/hipo.22612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Renata Bocian
- Department of Neurobiology; the University of Łódź; Pomorska Str. No 141/143 Łódź 91-236 Poland
| | - Paulina Kłos-Wojtczak
- Department of Neurobiology; the University of Łódź; Pomorska Str. No 141/143 Łódź 91-236 Poland
| | - Bartosz Caban
- Department of Neurobiology; the University of Łódź; Pomorska Str. No 141/143 Łódź 91-236 Poland
| | - Tomasz Kowalczyk
- Department of Neurobiology; the University of Łódź; Pomorska Str. No 141/143 Łódź 91-236 Poland
| | - Paulina Kaźmierska
- Department of Neurobiology; the University of Łódź; Pomorska Str. No 141/143 Łódź 91-236 Poland
| | - Jan Konopacki
- Department of Neurobiology; the University of Łódź; Pomorska Str. No 141/143 Łódź 91-236 Poland
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22
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Linley SB, Olucha-Bordonau F, Vertes RP. Pattern of distribution of serotonergic fibers to the amygdala and extended amygdala in the rat. J Comp Neurol 2016; 525:116-139. [PMID: 27213991 DOI: 10.1002/cne.24044] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 03/03/2016] [Accepted: 05/20/2016] [Indexed: 02/01/2023]
Abstract
As is well recognized, serotonergic (5-HT) fibers distribute widely throughout the forebrain, including the amygdala. Although a few reports have examined the 5-HT innervation of select nuclei of the amygdala in the rat, no previous report has described overall 5-HT projections to the amygdala in the rat. Using immunostaining for the serotonin transporter, SERT, we describe the complete pattern of distribution of 5-HT fibers to the amygdala (proper) and to the extended amygdala in the rat. Based on its ontogenetic origins, the amygdala was subdivided into two major parts, pallial and subpallial components, with the pallial component further divided into superficial and deep nuclei (Olucha-Bordonau et al. 2015). SERT+ fibers were shown to distributed moderately to densely to the deep and cortical pallial nuclei, but, by contrast, lightly to the subpallial nuclei. Specifically, 1) of the deep pallial nuclei, the lateral, basolateral, and basomedial nuclei contained a very dense concentration of 5-HT fibers; 2) of the cortical pallial nuclei, the anterior cortical and amygdala-cortical transition zone rostrally and the posteromedial and posterolateral nuclei caudally contained a moderate concentration of 5-HT fibers; and 3) of the subpallial nuclei, the anterior nuclei and the rostral part of the medial (Me) nuclei contained a moderate concentration of 5-HT fibers, whereas caudal regions of Me as well as the central nuclei and the intercalated nuclei contained a sparse/light concentration of 5-HT fibers. With regard to the extended amygdala (primarily the bed nucleus of stria terminalis; BST), on the whole, the BST contained moderate numbers of 5-HT fibers, spread fairly uniformly throughout BST. The findings are discussed with respect to a critical serotonergic influence on the amygdala, particularly on the basal complex, and on the extended amygdala in the control of states of fear and anxiety. J. Comp. Neurol. 525:116-139, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Stephanie B Linley
- Department of Psychology, Florida Atlantic University, Boca Raton, Florida, 33431.,Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida, 33431
| | - Francisco Olucha-Bordonau
- Departamento de Medicina, Facultad de Ciencias de la Salud, Universitat Jaume I, 12071, Castellón, Spain
| | - Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, Florida, 33431
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23
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Vertes RP, Hoover WB, Viana Di Prisco G. Theta Rhythm of the Hippocampus: Subcortical Control and Functional Significance. ACTA ACUST UNITED AC 2016; 3:173-200. [PMID: 15653814 DOI: 10.1177/1534582304273594] [Citation(s) in RCA: 160] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The theta rhythm is the largest extracellular synchronous signal that can be recorded from the mammalian brain and has been strongly implicated in mnemonic processes of the hippocampus. We describe (a) ascending brain stem–forebrain systems involved in controlling theta and nontheta (desynchronization) states of the hippocampal electroencephalogram; (b) theta rhythmically discharging cells in several structures of Papez's circuit and their possible functional significance, specifically with respect to head direction cells in this same circuit; and (c) the role of nucleus reuniens of the thalamus as a major interface between the medial prefrontal cortex and hippocampus and as a prominent source of afferent limbic information to the hippocampus. We suggest that the hippocampus receives two main types of input: theta rhythm from ascending brain stem– diencephaloseptal systems and information bearing mainly from thalamocortical/cortical systems. The temporal convergence of activity of these two systems results in the encoding of information in the hippocampus, primarily reaching it from the entorhinal cortex and nucleus reuniens.
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Biagioni AF, de Oliveira RC, de Oliveira R, da Silva JA, dos Anjos-Garcia T, Roncon CM, Corrado AP, Zangrossi H, Coimbra NC. 5-Hydroxytryptamine 1A receptors in the dorsomedial hypothalamus connected to dorsal raphe nucleus inputs modulate defensive behaviours and mediate innate fear-induced antinociception. Eur Neuropsychopharmacol 2016; 26:532-45. [PMID: 26749090 DOI: 10.1016/j.euroneuro.2015.12.032] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 12/09/2015] [Accepted: 12/14/2015] [Indexed: 02/04/2023]
Abstract
The dorsal raphe nucleus (DRN) is an important brainstem source of 5-hydroxytryptamine (5-HT), and 5-HT plays a key role in the regulation of panic attacks. The aim of the present study was to determine whether 5-HT1A receptor-containing neurons in the medial hypothalamus (MH) receive neural projections from DRN and to then determine the role of this neural substrate in defensive responses. The neurotracer biotinylated dextran amine (BDA) was iontophoretically microinjected into the DRN, and immunohistochemical approaches were then used to identify 5HT1A receptor-labelled neurons in the MH. Moreover, the effects of pre-treatment of the dorsomedial hypothalamus (DMH) with 8-OH-DPAT and WAY-100635, a 5-HT1A receptor agonist and antagonist, respectively, followed by local microinjections of bicuculline, a GABAA receptor antagonist, were investigated. We found that there are many projections from the DRN to the perifornical lateral hypothalamus (PeFLH) but also to DMH and ventromedial (VMH) nuclei, reaching 5HT1A receptor-labelled perikarya. DMH GABAA receptor blockade elicited defensive responses that were followed by antinociception. DMH treatment with 8-OH-DPAT decreased escape responses, which strongly suggests that the 5-HT1A receptor modulates the defensive responses. However, DMH treatment with WAY-100635 failed to alter bicuculline-induced defensive responses, suggesting that 5-HT exerts a phasic influence on 5-HT1A DMH neurons. The activation of the inhibitory 5-HT1A receptor had no effect on antinociception. However, blockade of the 5-HT1A receptor decreased fear-induced antinociception. The present data suggest that the ascending pathways from the DRN to the DMH modulate panic-like defensive behaviours and mediate antinociceptive phenomenon by recruiting 5-HT1A receptor in the MH.
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Affiliation(s)
- Audrey Franceschi Biagioni
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil
| | - Rithiele Cristina de Oliveira
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil
| | - Ricardo de Oliveira
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil; Mato Grosso Federal University Medical School (UFMT), Av. Alexandre Ferronato, 1200, Reserva 35, Setor Industrial, 78550-000 Sinop, Mato Grosso, Brazil
| | - Juliana Almeida da Silva
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil
| | - Tayllon dos Anjos-Garcia
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil
| | - Camila Marroni Roncon
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil
| | - Alexandre Pinto Corrado
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Hélio Zangrossi
- Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil; NAP-USP-Neurobiology of Emotions Research Centre (NuPNE), Ribeirão Preto Medical School of the University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Laboratory of Neuropsychopharmacology, Department of Pharmacology, Ribeirão Preto Medical School of the University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil
| | - Norberto Cysne Coimbra
- Laboratory of Neuroanatomy and Neuropsychobiology, Department of Pharmacology, Ribeirão Preto School of Medicine of the University of São Paulo (FMRP-USP), Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil; Behavioural Neurosciences Institute (INeC), Av. do Café, 2450, Monte Alegre, Ribeirão Preto, São Paulo 14050-220, Brazil; NAP-USP-Neurobiology of Emotions Research Centre (NuPNE), Ribeirão Preto Medical School of the University of São Paulo, Av. Bandeirantes, 3900, Ribeirão Preto, São Paulo 14049-900, Brazil.
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Wirtshafter D, Stratford TR. Chemogenetic inhibition of cells in the paramedian midbrain tegmentum increases locomotor activity in rats. Brain Res 2015; 1632:98-106. [PMID: 26707405 DOI: 10.1016/j.brainres.2015.12.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 11/21/2015] [Accepted: 12/09/2015] [Indexed: 11/17/2022]
Abstract
Pronounced hyperactivity can be produced by lesions or pharmacological inhibition of cells in the median raphe nucleus (MR) located in the paramedian midbrain tegmentum. In the current study we examined whether a similar effect can be seen after chemogenetic inhibition of cells in this region using the DREADD (Designer Receptors Exclusively Activated by Designer Drugs) approach. We found that the DREADD ligand clozapine-N-oxide (CNO) increased locomotor activity in animals expressing the inhibitory DREADD hM4Di, but not those injected with a control virus in the MR. The effect was of rapid onset and short duration and persisted for at least four months after virus injections. Histological examination of the brains indicated that labeled fibers followed the known projection patterns of the MR to a variety of forebrain and midbrain structures. These findings confirm the role of the MR region in the control of locomotion and suggest that the DREADD technique may be a useful approach to the study of the functional architecture of this complex area. Methodological and interpretive aspects of DREADD studies are discussed.
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Affiliation(s)
- David Wirtshafter
- Laboratory of Integrative Neuroscience, Department of Psychology (m/c 285), University of Illinois at Chicago, 1007 West Harrison Street, Chicago, IL 60607-7137, USA.
| | - Thomas R Stratford
- Laboratory of Integrative Neuroscience, Department of Psychology (m/c 285), University of Illinois at Chicago, 1007 West Harrison Street, Chicago, IL 60607-7137, USA
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26
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Hernández-Pérez JJ, Gutiérrez-Guzmán BE, López-Vázquez MÁ, Olvera-Cortés ME. Supramammillary serotonin reduction alters place learning and concomitant hippocampal, septal, and supramammillar theta activity in a Morris water maze. Front Pharmacol 2015; 6:250. [PMID: 26578960 PMCID: PMC4625187 DOI: 10.3389/fphar.2015.00250] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/14/2015] [Indexed: 11/29/2022] Open
Abstract
Hippocampal theta activity is related to spatial information processing, and high-frequency theta activity, in particular, has been linked to efficient spatial memory performance. Theta activity is regulated by the synchronizing ascending system (SAS), which includes mesencephalic and diencephalic relays. The supramamillary nucleus (SUMn) is located between the reticularis pontis oralis and the medial septum (MS), in close relation with the posterior hypothalamic nucleus (PHn), all of which are part of this ascending system. It has been proposed that the SUMn plays a role in the modulation of hippocampal theta-frequency; this could occur through direct connections between the SUMn and the hippocampus or through the influence of the SUMn on the MS. Serotonergic raphe neurons prominently innervate the hippocampus and several components of the SAS, including the SUMn. Serotonin desynchronizes hippocampal theta activity, and it has been proposed that serotonin may regulate learning through the modulation of hippocampal synchrony. In agreement with this hypothesis, serotonin depletion in the SUMn/PHn results in deficient spatial learning and alterations in CA1 theta activity-related learning in a Morris water maze. Because it has been reported that SUMn inactivation with lidocaine impairs the consolidation of reference memory, we asked whether changes in hippocampal theta activity related to learning would occur through serotonin depletion in the SUMn, together with deficiencies in memory. We infused 5,7-DHT bilaterally into the SUMn in rats and evaluated place learning in the standard Morris water maze task. Hippocampal (CA1 and dentate gyrus), septal and SUMn EEG were recorded during training of the test. The EEG power in each region and the coherence between the different regions were evaluated. Serotonin depletion in the SUMn induced deficient spatial learning and altered the expression of hippocampal high-frequency theta activity. These results provide evidence in support of a role for serotonin as a modulator of hippocampal learning, acting through changes in the synchronicity evoked in several relays of the SAS.
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Affiliation(s)
- J. Jesús Hernández-Pérez
- Laboratorio de Neurofisiología Experimental, División de Neurociencias, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro SocialMorelia, México
| | - Blanca E. Gutiérrez-Guzmán
- Laboratorio de Neurofisiología Experimental, División de Neurociencias, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro SocialMorelia, México
| | - Miguel Á. López-Vázquez
- Laboratorio de Neuroplasticidad de los Procesos Cognitivos, División de Neurociencias, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro SocialMorelia, México
- Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de HidalgoMorelia, México
| | - María E. Olvera-Cortés
- Laboratorio de Neurofisiología Experimental, División de Neurociencias, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro SocialMorelia, México
- *Correspondence: María E. Olvera-Cortés
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Bland BH, Bland CE, MacIver MB. Median raphe stimulation-induced motor inhibition concurrent with suppression of type 1 and type 2 hippocampal theta. Hippocampus 2015; 26:289-300. [PMID: 26314691 DOI: 10.1002/hipo.22521] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 08/24/2015] [Accepted: 08/24/2015] [Indexed: 11/10/2022]
Abstract
This study investigated behavioral, anatomical and electrophysiological effects produced by electrical stimulation of posterior hypothalamic (PH) or median raphe (MR) nuclei, independently and during combined stimulation of both PH and MR. These three stimulation conditions were applied during spontaneous behavior in an open field and during PH stimulation-induced wheel running, while simultaneously recording hippocampal (HPC) field activity. An additional objective was to determine the effects of MR stimulation on Type 1 movement related theta and Type 2 sensory processing related theta. To achieve the latter, when behavioral studies were completed we studied the same rats under urethane anesthesia and then during urethane anesthesia with the addition of atropine sulfate (ATSO4). Here we demonstrated that electrical stimulation of a localized region of the MR nucleus resulted in a profound inhibition of both spontaneously occurring theta related motor behaviors and the theta related motor behaviors induced by electrical stimulation of the PH nucleus. Furthermore, this motor inhibition occurred concurrently with strong suppression of hippocampal theta field oscillations in the freely moving rat, a condition where the theta recorded is Type 2 sensory processing theta occurring coincidently with Type 1 movement related theta (Bland, 1986). Our results indicate that motor inhibition resulted from stimulation of neurons located in the mid central region of the MR, while stimulation in adjacent regions produced variable responses, including movements and theta activity. The present study provided evidence that the pharmacological basis of the suppression of Type 2 sensory processing HPC theta was cholinergic. However, MR inhibition of PH-induced wheel running was not affected by cholinergic blockade, which blocks Type 2 theta, indicating that MR stimulation-induced motor inhibition also requires the suppression of Type 1 theta.
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Affiliation(s)
- Brian H Bland
- Department of Psychology, Behavioral Neuroscience Research Group, the University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, Faculty of Medicine, the University of Calgary, Calgary, Alberta, Canada
| | - Cheryl E Bland
- Department of Psychology, Behavioral Neuroscience Research Group, the University of Calgary, Calgary, Alberta, Canada
| | - M Bruce MacIver
- Neuropharmacology Laboratory, Stanford School of Medicine, Stanford, California
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28
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Kirouac GJ. Placing the paraventricular nucleus of the thalamus within the brain circuits that control behavior. Neurosci Biobehav Rev 2015; 56:315-29. [DOI: 10.1016/j.neubiorev.2015.08.005] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 07/29/2015] [Accepted: 08/04/2015] [Indexed: 11/16/2022]
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29
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Deusser J, Schmidt S, Ettle B, Plötz S, Huber S, Müller CP, Masliah E, Winkler J, Kohl Z. Serotonergic dysfunction in the A53T alpha-synuclein mouse model of Parkinson's disease. J Neurochem 2015. [PMID: 26201615 DOI: 10.1111/jnc.13253] [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: 12/31/2022]
Abstract
Parkinson's disease, neuropathologically defined by the aggregation of α-synuclein, is characterized by neuropsychiatric symptoms such as depression and anxiety preceding the onset of motor symptoms. A loss of serotonergic neurons or their projections into the hippocampus and alterations in serotonin release may be linked to these symptoms. Here, we investigate the effect of human A53T α-synuclein on serotonergic neurons using 12-months-old transgenic mice. We detected human α-synuclein in the perikarya of brainstem median and dorsal raphe neurons as well as in serotonergic fibers in the hippocampus. Despite intracellular α-synuclein accumulation there was no loss of serotonergic neurons in dorsal and median raphe nuclei of A53T α-synuclein mice. However, serotonin levels were significantly reduced in the brainstem. In addition, serotonergic fiber density in the dorsal dentate gyrus was significantly less dense in transgenic mice. Interestingly, we detected a significantly compromised increase in doublecortin+ neuroblasts after chronic treatment with fluoxetine at the site of reduced serotonergic innervation, the infrapyramidal blade of the dorsal dentate gyrus in A53T α-synuclein mice. This suggests that α-synuclein affects serotonergic projections in a spatially distinct pattern within the hippocampus thereby influencing the response to antidepressant treatment.
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Affiliation(s)
- Janina Deusser
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Stefanie Schmidt
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Benjamin Ettle
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Sonja Plötz
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Sabine Huber
- Section of Addiction Medicine, Department of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Christian P Müller
- Section of Addiction Medicine, Department of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Eliezer Masliah
- Department of Neurosciences and Pathology, University of California San Diego, La Jolla, California, USA
| | - Jürgen Winkler
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Zacharias Kohl
- Department of Molecular Neurology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
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Vertes RP, Linley SB, Hoover WB. Limbic circuitry of the midline thalamus. Neurosci Biobehav Rev 2015; 54:89-107. [PMID: 25616182 PMCID: PMC4976455 DOI: 10.1016/j.neubiorev.2015.01.014] [Citation(s) in RCA: 241] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 12/19/2014] [Accepted: 01/12/2015] [Indexed: 01/01/2023]
Abstract
The thalamus was subdivided into three major groups: sensorimotor nuclei (or principal/relay nuclei), limbic nuclei and nuclei bridging these two domains. Limbic nuclei of thalamus (or 'limbic thalamus') consist of the anterior nuclei, midline nuclei, medial division of the mediodorsal nucleus (MDm) and central medial nucleus (CM) of the intralaminar complex. The midline nuclei include the paraventricular (PV) and paratenial (PT) nuclei, dorsally, and the reuniens (RE) and rhomboid (RH) nuclei, ventrally. The 'limbic' thalamic nuclei predominantly connect with limbic-related structures and serve a direct role in limbic-associated functions. Regarding the midline nuclei, RE/RH mainly target limbic cortical structures, particularly the hippocampus and the medial prefrontal cortex. Accordingly, RE/RH participate in functions involving interactions of the HF and mPFC. By contrast, PV/PT mainly project to limbic subcortical structures, particularly the amygdala and nucleus accumbens, and hence are critically involved in affective behaviors such as stress/anxiety, feeding behavior, and drug seeking activities. The anatomical/functional characteristics of MDm and CM are very similar to those of the midline nuclei and hence the collection of nuclei extending dorsoventrally along the midline/paramidline of the thalamus constitute the core of the 'limbic thalamus'.
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Affiliation(s)
- Robert P Vertes
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, United States.
| | - Stephanie B Linley
- Center for Complex Systems and Brain Sciences, Florida Atlantic University, Boca Raton, FL 33431, United States
| | - Walter B Hoover
- Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, United States
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31
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Ma S, Gundlach AL. Ascending control of arousal and motivation: role of nucleus incertus and its peptide neuromodulators in behavioural responses to stress. J Neuroendocrinol 2015; 27:457-67. [PMID: 25612218 DOI: 10.1111/jne.12259] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 01/12/2015] [Accepted: 01/15/2015] [Indexed: 02/06/2023]
Abstract
Arousal is a process that involves the activation of ascending neural pathways originating in the rostral pons that project to the forebrain through the midbrain reticular formation to promote the activation of key cortical, thalamic, hypothalamic and limbic centres. Established modulators of arousal include the cholinergic, serotonergic, noradrenergic and dopaminergic networks originating in the pons and midbrain. Recent data indicate that a population of largely GABAergic projection neurones located in the nucleus incertus (NI) are also involved in arousal and motivational processes. The NI has prominent efferent connections with distinct hypothalamic, amygdalar and thalamic nuclei, in addition to dense projections to key brain regions associated with the generation and pacing of hippocampal activity. The NI receives strong inputs from the prefrontal cortex, lateral habenula and the interpeduncular and median raphe nuclei, suggesting it is highly integrated in circuits regulating higher cognitive behaviours (hippocampal theta rhythm) and emotion. Anatomical and functional studies have revealed that the NI is a rich source of multiple peptide neuromodulators, including relaxin-3, and may mediate extra-hypothalamic effects of the stress hormone corticotrophin-releasing factor, as well as other key modulators such as orexins and oxytocin. This review provides an overview of earlier studies and highlights more recent research that implicates this neural network in the integration of arousal and motivated behaviours and has begun to identify the associated mechanisms. Future research that should help to better clarify the connectivity and function of the NI in major experimental species and humans is also discussed.
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Affiliation(s)
- S Ma
- Neuropeptides Division, The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
| | - A L Gundlach
- Neuropeptides Division, The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia
- Department of Anatomy and Neuroscience, The University of Melbourne, Melbourne, VIC, Australia
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32
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Szőnyi A, Mayer MI, Cserép C, Takács VT, Watanabe M, Freund TF, Nyiri G. The ascending median raphe projections are mainly glutamatergic in the mouse forebrain. Brain Struct Funct 2014; 221:735-51. [PMID: 25381463 DOI: 10.1007/s00429-014-0935-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/28/2014] [Indexed: 12/26/2022]
Abstract
The median raphe region (MRR) is thought to be serotonergic and plays an important role in the regulation of many cognitive functions. In the hippocampus (HIPP), the MRR exerts a fast excitatory control, partially through glutamatergic transmission, on a subpopulation of GABAergic interneurons that are key regulators of local network activity. However, not all receptors of this connection in the HIPP and in synapses established by MRR in other brain areas are known. Using combined anterograde tracing and immunogold methods, we show that the GluN2A subunit of the NMDA receptor is present in the synapses established by MRR not only in the HIPP, but also in the medial septum (MS) and in the medial prefrontal cortex (mPFC) of the mouse. We estimated similar amounts of NMDA receptors in these synapses established by the MRR and in local adjacent excitatory synapses. Using retrograde tracing and confocal laser scanning microscopy, we found that the majority of the projecting cells of the mouse MRR contain the vesicular glutamate transporter type 3 (vGluT3). Furthermore, using double retrograde tracing, we found that single cells of the MRR can innervate the HIPP and mPFC or the MS and mPFC simultaneously, and these double-projecting cells are also predominantly vGluT3-positive. Our results indicate that the majority of the output of the MRR is glutamatergic and acts through NMDA receptor-containing synapses. This suggests that key forebrain areas receive precisely targeted excitatory input from the MRR, which is able to synchronously modify activity in those regions via individual MRR cells with dual projections.
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Affiliation(s)
- András Szőnyi
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, 1085, Hungary
| | - Márton I Mayer
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Csaba Cserép
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Virág T Takács
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo, 060-8638, Japan
| | - Tamás F Freund
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary
| | - Gábor Nyiri
- Laboratory of Cerebral Cortex Research, Institute of Experimental Medicine Hungarian Academy of Sciences, Budapest, 1083, Hungary.
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33
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de Medeiros Silva A, de Santana MAD, de Góis Morais PLA, de Sousa TB, Januário Engelberth RCG, de Souza Lucena EE, Campêlo CLDC, Sousa Cavalcante J, Cavalcante JC, de Oliveira Costa MSM, Nascimento ESD. Serotonergic fibers distribution in the midline and intralaminar thalamic nuclei in the rock cavy (Kerodon rupestris). Brain Res 2014; 1586:99-108. [DOI: 10.1016/j.brainres.2014.08.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/14/2014] [Accepted: 08/16/2014] [Indexed: 12/19/2022]
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34
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Jang SH, Lim HW, Yeo SS. The neural connectivity of the intralaminar thalamic nuclei in the human brain: A diffusion tensor tractography study. Neurosci Lett 2014; 579:140-4. [DOI: 10.1016/j.neulet.2014.07.024] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 06/19/2014] [Accepted: 07/11/2014] [Indexed: 11/27/2022]
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35
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Leung LS, Luo T, Ma J, Herrick I. Brain areas that influence general anesthesia. Prog Neurobiol 2014; 122:24-44. [PMID: 25172271 DOI: 10.1016/j.pneurobio.2014.08.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 08/03/2014] [Accepted: 08/19/2014] [Indexed: 10/24/2022]
Abstract
This document reviews the literature on local brain manipulation of general anesthesia in animals, focusing on behavioral and electrographic effects related to hypnosis or loss of consciousness. Local inactivation or lesion of wake-active areas, such as locus coeruleus, dorsal raphe, pedunculopontine tegmental nucleus, perifornical area, tuberomammillary nucleus, ventral tegmental area and basal forebrain, enhanced general anesthesia. Anesthesia enhancement was shown as a delayed emergence (recovery of righting reflex) from anesthesia or a decrease in the minimal alveolar concentration that induced loss of righting. Local activation of various wake-active areas, including pontis oralis and centromedial thalamus, promoted behavioral or electrographic arousal during maintained anesthesia and facilitated emergence. Lesion of the sleep-active ventrolateral preoptic area resulted in increased wakefulness and decreased isoflurane sensitivity, but only for 6 days after lesion. Inactivation of any structure within limbic circuits involving the medial septum, hippocampus, nucleus accumbens, ventral pallidum, and ventral tegmental area, amygdala, entorhinal and piriform cortex delayed emergence from anesthesia, and often reduced anesthetic-induced behavioral excitation. In summary, the concept that anesthesia works on the sleep-wake system has received strong support from studies that inactivated/lesioned or activated wake-active areas, and weak support from studies that lesioned sleep-active areas. In addition to the conventional wake-sleep areas, limbic structures such as the medial septum, hippocampus and prefrontal cortex are also involved in the behavioral response to general anesthesia. We suggest that hypnosis during general anesthesia may result from disrupting the wake-active neuronal activities in multiple areas and suppressing an atropine-resistant cortical activation associated with movements.
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Affiliation(s)
- L Stan Leung
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada N6A 5C1.
| | - Tao Luo
- Department of Anesthesiology, Peking University, Shenzhen Hospital, China
| | - Jingyi Ma
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada N6A 5C1
| | - Ian Herrick
- Department of Anaesthesiology and Perioperative Medicine, The University of Western Ontario, London, Ontario, Canada N6A 5C1
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López-Vázquez MÁ, López-Loeza E, Lajud Ávila N, Gutiérrez-Guzmán BE, Hernández-Pérez JJ, Reyes YE, Olvera-Cortés ME. Septal serotonin depletion in rats facilitates working memory in the radial arm maze and increases hippocampal high-frequency theta activity. Eur J Pharmacol 2014; 734:105-13. [PMID: 24742376 DOI: 10.1016/j.ejphar.2014.04.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Revised: 04/01/2014] [Accepted: 04/03/2014] [Indexed: 11/27/2022]
Abstract
Hippocampal theta activity, which is strongly modulated by the septal medial/Broca׳s diagonal band neurons, has been linked to information processing of the hippocampus. Serotonin from the medial raphe nuclei desynchronises hippocampal theta activity, whereas inactivation or a lesion of this nucleus induces continuous and persistent theta activity in the hippocampus. Hippocampal serotonin depletion produces an increased expression of high-frequency theta activity concurrent with the facilitation of place learning in the Morris maze. The medial septum-diagonal band of Broca complex (MS/DBB) has been proposed as a key structure in the serotonin modulation of theta activity. We addressed whether serotonin depletion of the MS/DBB induces changes in the characteristics of hippocampal theta activity and whether the depletion is associated with learning in a working memory spatial task in the radial arm maze. Sprague Dawley rats were depleted of 5HT with the infusion of 5,7-dihydroxytriptamine (5,7-DHT) in MS/DBB and were subsequently trained in the standard test (win-shift) in the radial arm, while the CA1 EEG activity was simultaneously recorded through telemetry. The MS/DBB serotonin depletion induced a low level of expression of low-frequency (4.5-6.5Hz) and a higher expression of high-frequency (6.5-9.5Hz) theta activity concomitant to a minor number of errors committed by rats on the working memory test. Thus, the depletion of serotonin in the MS/DBB caused a facilitator effect on working memory and a predominance of high-frequency theta activity.
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Affiliation(s)
- Miguel Ángel López-Vázquez
- Laboratorio de Neuroplasticidad de los Procesos Cognitivos, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, Mexico; Laboratorio de Biofísica, Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, Mexico
| | - Elisa López-Loeza
- Laboratorio de Biofísica, Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo, Mexico
| | - Naima Lajud Ávila
- Laboratorio de Neuroendocrinología, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, Mexico
| | - Blanca Erika Gutiérrez-Guzmán
- Laboratorio de Neurofisiología Experimental, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, Camino de la arboleda 300, Exhacienda de san José de la Huerta, Morelia, Mich C.P. 58341, Mexico
| | - J Jesús Hernández-Pérez
- Laboratorio de Neurofisiología Experimental, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, Camino de la arboleda 300, Exhacienda de san José de la Huerta, Morelia, Mich C.P. 58341, Mexico
| | - Yoana Estrada Reyes
- Laboratorio de Neuroplasticidad de los Procesos Cognitivos, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, Mexico
| | - María Esther Olvera-Cortés
- Laboratorio de Neurofisiología Experimental, Centro de Investigación Biomédica de Michoacán, Instituto Mexicano del Seguro Social, Camino de la arboleda 300, Exhacienda de san José de la Huerta, Morelia, Mich C.P. 58341, Mexico
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Differential trigeminovascular nociceptive responses in the thalamus in the familial hemiplegic migraine 1 knock-in mouse: A Fos protein study. Neurobiol Dis 2014; 64:1-7. [DOI: 10.1016/j.nbd.2013.12.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 11/15/2013] [Accepted: 12/08/2013] [Indexed: 11/16/2022] Open
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Smith Y, Galvan A, Ellender TJ, Doig N, Villalba RM, Huerta-Ocampo I, Wichmann T, Bolam JP. The thalamostriatal system in normal and diseased states. Front Syst Neurosci 2014; 8:5. [PMID: 24523677 PMCID: PMC3906602 DOI: 10.3389/fnsys.2014.00005] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 01/11/2014] [Indexed: 11/13/2022] Open
Abstract
Because of our limited knowledge of the functional role of the thalamostriatal system, this massive network is often ignored in models of the pathophysiology of brain disorders of basal ganglia origin, such as Parkinson's disease (PD). However, over the past decade, significant advances have led to a deeper understanding of the anatomical, electrophysiological, behavioral and pathological aspects of the thalamostriatal system. The cloning of the vesicular glutamate transporters 1 and 2 (vGluT1 and vGluT2) has provided powerful tools to differentiate thalamostriatal from corticostriatal glutamatergic terminals, allowing us to carry out comparative studies of the synaptology and plasticity of these two systems in normal and pathological conditions. Findings from these studies have led to the recognition of two thalamostriatal systems, based on their differential origin from the caudal intralaminar nuclear group, the center median/parafascicular (CM/Pf) complex, or other thalamic nuclei. The recent use of optogenetic methods supports this model of the organization of the thalamostriatal systems, showing differences in functionality and glutamate receptor localization at thalamostriatal synapses from Pf and other thalamic nuclei. At the functional level, evidence largely gathered from thalamic recordings in awake monkeys strongly suggests that the thalamostriatal system from the CM/Pf is involved in regulating alertness and switching behaviors. Importantly, there is evidence that the caudal intralaminar nuclei and their axonal projections to the striatum partly degenerate in PD and that CM/Pf deep brain stimulation (DBS) may be therapeutically useful in several movement disorders.
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Affiliation(s)
- Yoland Smith
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; Department of Neurology, Emory University Atlanta, GA, USA ; Udall Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA
| | - Adriana Galvan
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; Department of Neurology, Emory University Atlanta, GA, USA ; Udall Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA
| | - Tommas J Ellender
- Department of Pharmacology, MRC Anatomical Neuropharmacology Unit Oxford, UK
| | - Natalie Doig
- Department of Pharmacology, MRC Anatomical Neuropharmacology Unit Oxford, UK
| | - Rosa M Villalba
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; Udall Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA
| | | | - Thomas Wichmann
- Yerkes National Primate Research Center, Emory University Atlanta, GA, USA ; Department of Neurology, Emory University Atlanta, GA, USA ; Udall Center of Excellence for Parkinson's Disease, Emory University Atlanta, GA, USA
| | - J Paul Bolam
- Department of Pharmacology, MRC Anatomical Neuropharmacology Unit Oxford, UK
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Ohta K, Miki T, Warita K, Suzuki S, Kusaka T, Yakura T, Liu J, Tamai M, Takeuchi Y. Prolonged maternal separation disturbs the serotonergic system during early brain development. Int J Dev Neurosci 2013; 33:15-21. [DOI: 10.1016/j.ijdevneu.2013.10.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 10/18/2013] [Accepted: 10/23/2013] [Indexed: 12/14/2022] Open
Affiliation(s)
- Ken‐ichi Ohta
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
| | - Takanori Miki
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
| | - Katsuhiko Warita
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
- Department of PathologyDivision of Molecular DiagnosticsUniversity of Pittsburgh School of MedicinePittsburghPAUSA
| | - Shingo Suzuki
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
| | - Takashi Kusaka
- Department of PediatricsFaculty of MedicineKagawa UniversityKagawaJapan
| | - Tomiko Yakura
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
| | - Jun‐Qian Liu
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
| | - Motoki Tamai
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
| | - Yoshiki Takeuchi
- Department of Anatomy and NeurobiologyFaculty of MedicineKagawa UniversityKagawaJapan
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Celio MR, Babalian A, Ha QH, Eichenberger S, Clément L, Marti C, Saper CB. Efferent connections of the parvalbumin-positive (PV1) nucleus in the lateral hypothalamus of rodents. J Comp Neurol 2013; 521:3133-53. [PMID: 23787784 PMCID: PMC3772778 DOI: 10.1002/cne.23344] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 03/28/2013] [Accepted: 04/05/2013] [Indexed: 11/07/2022]
Abstract
A solitary cluster of parvalbumin-positive neurons--the PV1 nucleus--has been observed in the lateral hypothalamus of rodents. In the present study, we mapped the efferent connections of the PV1 nucleus using nonspecific antero- and retrograde tracers in rats, and chemoselective, Cre-dependent viral constructs in parvalbumin-Cre mice. In both species, the PV1 nucleus was found to project mainly to the periaqueductal grey matter (PAG), predominantly ipsilaterally. Indirectly in rats and directly in mice, a discrete, longitudinally oriented cylindrical column of terminal fields (PV1-CTF) was identified ventrolateral to the aqueduct on the edge of the PAG. The PV1-CTF is particularly dense in the rostral portion, which is located in the supraoculomotor nucleus (Su3). It is spatially interrupted over a short stretch at the level of the trochlear nucleus and abuts caudally on a second parvalbumin-positive (PV2) nucleus. The rostral and the caudal portions of the PV1-CTF consist of axonal endings, which stem from neurons scattered throughout the PV1 nucleus. Topographically, the longitudinal orientation of the PV1-CTF accords with that of the likewise longitudinally oriented functional modules of the PAG, but overlaps none of them. Minor terminal fields were identified in a crescentic column of the lateral PAG, as well as in the Edinger-Westphal, the lateral habenular, and the laterodorsal tegmental nuclei. So far, no obvious functions have been attributed to this small, circumscribed column ventrolateral to the aqueduct, the prime target of the PV1 nucleus.
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Affiliation(s)
- Marco R. Celio
- Anatomy Unit, Department of Medicine and “Program
in Neuroscience”, University of Fribourg, CH-1700 Fribourg
- Department of Neurology and “Program in
Neuroscience”, Harvard Medical School, Beth Israel Deaconess Medical Center,
330 Brookline Avenue, Boston, MA 02215, USA
| | - Alexander Babalian
- Anatomy Unit, Department of Medicine and “Program
in Neuroscience”, University of Fribourg, CH-1700 Fribourg
| | - Quan Hue Ha
- Department of Neurology and “Program in
Neuroscience”, Harvard Medical School, Beth Israel Deaconess Medical Center,
330 Brookline Avenue, Boston, MA 02215, USA
| | - Simone Eichenberger
- Anatomy Unit, Department of Medicine and “Program
in Neuroscience”, University of Fribourg, CH-1700 Fribourg
| | - Laurence Clément
- Anatomy Unit, Department of Medicine and “Program
in Neuroscience”, University of Fribourg, CH-1700 Fribourg
| | - Christiane Marti
- Anatomy Unit, Department of Medicine and “Program
in Neuroscience”, University of Fribourg, CH-1700 Fribourg
| | - Clifford B. Saper
- Department of Neurology and “Program in
Neuroscience”, Harvard Medical School, Beth Israel Deaconess Medical Center,
330 Brookline Avenue, Boston, MA 02215, USA
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41
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León-Domínguez U, Vela-Bueno A, Froufé-Torres M, León-Carrión J. A chronometric functional sub-network in the thalamo-cortical system regulates the flow of neural information necessary for conscious cognitive processes. Neuropsychologia 2013; 51:1336-49. [DOI: 10.1016/j.neuropsychologia.2013.03.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 03/13/2013] [Accepted: 03/21/2013] [Indexed: 01/28/2023]
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McNab JA, Edlow BL, Witzel T, Huang SY, Bhat H, Heberlein K, Feiweier T, Liu K, Keil B, Cohen-Adad J, Tisdall MD, Folkerth RD, Kinney HC, Wald LL. The Human Connectome Project and beyond: initial applications of 300 mT/m gradients. Neuroimage 2013; 80:234-45. [PMID: 23711537 DOI: 10.1016/j.neuroimage.2013.05.074] [Citation(s) in RCA: 255] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Revised: 05/07/2013] [Accepted: 05/13/2013] [Indexed: 01/01/2023] Open
Abstract
The engineering of a 3 T human MRI scanner equipped with 300 mT/m gradients - the strongest gradients ever built for an in vivo human MRI scanner - was a major component of the NIH Blueprint Human Connectome Project (HCP). This effort was motivated by the HCP's goal of mapping, as completely as possible, the macroscopic structural connections of the in vivo healthy, adult human brain using diffusion tractography. Yet, the 300 mT/m gradient system is well suited to many additional types of diffusion measurements. Here, we present three initial applications of the 300 mT/m gradients that fall outside the immediate scope of the HCP. These include: 1) diffusion tractography to study the anatomy of consciousness and the mechanisms of brain recovery following traumatic coma; 2) q-space measurements of axon diameter distributions in the in vivo human brain and 3) postmortem diffusion tractography as an adjunct to standard histopathological analysis. We show that the improved sensitivity and diffusion-resolution provided by the gradients are rapidly enabling human applications of techniques that were previously possible only for in vitro and animal models on small-bore scanners, thereby creating novel opportunities to map the microstructure of the human brain in health and disease.
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Affiliation(s)
- Jennifer A McNab
- Department of Radiology, Stanford University, RM Lucas Center for Imaging, Stanford, CA, USA.
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Continuously tracing brain-wide long-distance axonal projections in mice at a one-micron voxel resolution. Neuroimage 2013; 74:87-98. [PMID: 23416252 DOI: 10.1016/j.neuroimage.2013.02.005] [Citation(s) in RCA: 143] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Revised: 02/01/2013] [Accepted: 02/05/2013] [Indexed: 11/21/2022] Open
Abstract
Revealing neural circuit mechanisms is critical for understanding brain functions. Significant progress in dissecting neural connections has been made using optical imaging with fluorescence labels, especially in dissecting local connections. However, acquiring and tracing brain-wide, long-distance neural circuits at the neurite level remains a substantial challenge. Here, we describe a whole-brain approach to systematically obtaining continuous neuronal pathways in a fluorescent protein transgenic mouse at a one-micron voxel resolution. This goal is achieved by combining a novel resin-embedding method for maintaining fluorescence, an automated fluorescence micro-optical sectioning tomography system for long-term stable imaging, and a digital reconstruction-registration-annotation pipeline for tracing the axonal pathways in the mouse brain. With the unprecedented ability to image a whole mouse brain at a one-micron voxel resolution, the long-distance pathways were traced minutely and without interruption for the first time. With advancing labeling techniques, our method is believed to open an avenue to exploring both local and long-distance neural circuits that are related to brain functions and brain diseases down to the neurite level.
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Linley SB, Hoover WB, Vertes RP. Pattern of distribution of serotonergic fibers to the orbitomedial and insular cortex in the rat. J Chem Neuroanat 2013; 48-49:29-45. [PMID: 23337940 DOI: 10.1016/j.jchemneu.2012.12.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Revised: 12/13/2012] [Accepted: 12/14/2012] [Indexed: 01/23/2023]
Abstract
As is well recognized, serotonergic (5-HT) fibers distribute widely throughout the brain, including the cerebral cortex. Although some early reports described the 5-HT innervation of the prefrontal cortex (PFC) in rats, the focus was on sensorimotor regions and not on the 'limbic' PFC - or on the medial, orbital and insular cortices. In addition, no reports have described the distribution of 5-HT fibers to PFC in rats using antisera to the serotonin transporter (SERT). Using immunostaining for SERT, we examined the pattern of distribution of 5-HT fibers to the medial, orbital and insular cortices in the rat. We show that 5-HT fibers distribute massively throughout all divisions of the PFC, with distinct laminar variations. Specifically, 5-HT fibers were densely concentrated in superficial (layer 1) and deep (layers 5/6) of the PFC but less heavily so in intermediate layers (layers 2/3). This pattern was most pronounced in the orbital cortex, particularly in the ventral and ventrolateral orbital cortices. With the emergence of granular divisions of the insular cortex, the granular cell layer (layer 4) was readily identifiable by a dense band of labeling confined to it, separating layer 4 from less heavily labeled superficial and deep layers. The pattern of 5-HT innervation of medial, orbital and insular cortices significantly differed from that of sensorimotor regions of the PFC. Serotonergic labeling was much denser overall in limbic compared to non-limbic regions of the PFC, as was striking demonstrated by the generally weaker labeling in layers 1-3 of the primary sensory and motor cortices. The massive serotonergic innervation of the medial, orbital and insular divisions of the PFC likely contributes substantially to well established serotonergic effects on affective and cognitive functions, including a key role in many neurological and psychiatric diseases.
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Affiliation(s)
- Stephanie B Linley
- Department of Psychology, Florida Atlantic University, Boca Raton, FL 33431, United States
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45
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Gonçalves L, Sego C, Metzger M. Differential projections from the lateral habenula to the rostromedial tegmental nucleus and ventral tegmental area in the rat. J Comp Neurol 2012; 520:1278-300. [PMID: 22020635 DOI: 10.1002/cne.22787] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The mesopontine rostromedial tegmental nucleus (RMTg) is a mostly γ-aminobutyric acid (GABA)ergic structure believed to be a node for signaling aversive events to dopamine (DA) neurons in the ventral tegmental area (VTA). The RMTg receives glutamatergic inputs from the lateral habenula (LHb) and sends substantial GABAergic projections to the VTA, which also receives direct projections from the LHb. To further specify the topography of LHb projections to the RMTg and VTA, small focal injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin were aimed at different subdivisions of the LHb. The subnuclear origin of LHb inputs to the VTA and RMTg was then confirmed by injections of the retrograde tracer cholera toxin subunit b into the VTA or RMTg. Furthermore, we compared the topographic position of retrogradely labeled neurons in the RMTg resulting from VTA injections with that of anterogradely labeled axons emerging from the LHb. As revealed by anterograde and retrograde tracing, LHb projections were organized in a strikingly topographic manner, with inputs to the RMTg mostly arising from the lateral division of the LHb (LHbL), whereas inputs to the VTA mainly emerged from the medial division of the LHb (LHbM). In the RMTg, profusely branched LHb axons were found in close register with VTA projecting neurons and were frequently apposed to the latter. Overall, our findings demonstrate that LHb inputs to the RMTg and VTA arise from different divisions of the LHb and provide direct evidence for a disynaptic pathway that links the LHbL to the VTA via the RMTg.
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Affiliation(s)
- Luciano Gonçalves
- Department of Physiology & Biophysics, Institute of Biomedical Sciences, University of São Paulo, 05508-900 São Paulo, Brazil
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Development of the serotonergic cells in murine raphe nuclei and their relations with rhombomeric domains. Brain Struct Funct 2012; 218:1229-77. [PMID: 23052546 PMCID: PMC3748323 DOI: 10.1007/s00429-012-0456-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 09/08/2012] [Indexed: 12/18/2022]
Abstract
The raphe nuclei represent the origin of central serotonergic projections. The literature distinguishes seven nuclei grouped into rostral and caudal clusters relative to the pons. The boundaries of these nuclei have not been defined precisely enough, particularly with regard to developmental units, notably hindbrain rhombomeres. We hold that a developmental point of view considering rhombomeres may explain observed differences in connectivity and function. There are twelve rhombomeres characterized by particular genetic profiles, and each develops between one and four distinct serotonergic populations. We have studied the distribution of the conventional seven raphe nuclei among these twelve units. To this aim, we correlated 5-HT-immunoreacted neurons with rhombomeric boundary landmarks in sagittal mouse brain sections at different developmental stages. Furthermore, we performed a partial genoarchitectonic analysis of the developing raphe nuclei, mapping all known serotonergic differentiation markers, and compared these results, jointly with others found in the literature, with our map of serotonin-containing populations, in order to examine regional variations in correspondence. Examples of regionally selective gene patterns were identified. As a result, we produced a rhombomeric classification of some 45 serotonergic populations, and suggested a corresponding modified terminology. Only a minor rostral part of the dorsal raphe nucleus lies in the midbrain. Some serotonergic neurons were found in rhombomere 4, contrary to the conventional assumption that it lacks such neurons. We expect that our reclassification of raphe nuclei may be useful for causal analysis of their differential molecular specification, as well as for studies of differential connectivity and function.
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Projections of the central medial nucleus of the thalamus in the rat: Node in cortical, striatal and limbic forebrain circuitry. Neuroscience 2012; 219:120-36. [DOI: 10.1016/j.neuroscience.2012.04.067] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 04/17/2012] [Accepted: 04/29/2012] [Indexed: 12/30/2022]
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48
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Neuroanatomic connectivity of the human ascending arousal system critical to consciousness and its disorders. J Neuropathol Exp Neurol 2012; 71:531-46. [PMID: 22592840 DOI: 10.1097/nen.0b013e3182588293] [Citation(s) in RCA: 290] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The ascending reticular activating system (ARAS) mediates arousal, an essential component of human consciousness. Lesions of the ARAS cause coma, the most severe disorder of consciousness. Because of current methodological limitations, including of postmortem tissue analysis, the neuroanatomic connectivity of the human ARAS is poorly understood. We applied the advanced imaging technique of high angular resolution diffusion imaging (HARDI) to elucidate the structural connectivity of the ARAS in 3 adult human brains, 2 of which were imaged postmortem. High angular resolution diffusion imaging tractography identified the ARAS connectivity previously described in animals and also revealed novel human pathways connecting the brainstem to the thalamus, the hypothalamus, and the basal forebrain. Each pathway contained different distributions of fiber tracts from known neurotransmitter-specific ARAS nuclei in the brainstem. The histologically guided tractography findings reported here provide initial evidence for human-specific pathways of the ARAS. The unique composition of neurotransmitter-specific fiber tracts within each ARAS pathway suggests structural specializations that subserve the different functional characteristics of human arousal. This ARAS connectivity analysis provides proof of principle that HARDI tractography may affect the study of human consciousness and its disorders, including in neuropathologic studies of patients dying in coma and the persistent vegetative state.
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49
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Origins of arousal: roles for medullary reticular neurons. Trends Neurosci 2012; 35:468-76. [PMID: 22626543 DOI: 10.1016/j.tins.2012.04.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 04/18/2012] [Accepted: 04/23/2012] [Indexed: 01/12/2023]
Abstract
The existence of a primitive CNS function involved in the activation of all vertebrate behaviors, generalized arousal (GA), has been proposed. Here, we provide an overview of the neuroanatomical, neurophysiological and molecular properties of reticular neurons within the nucleus gigantocellularis (NGC) of the mammalian medulla, and propose that the properties of these neurons equip them to contribute powerfully to GA. We also explore the hypothesis that these neurons may have evolved from the Mauthner cell in the medulla of teleost fish, although NGC neurons have a wider range of action far beyond the specific escape network served by Mauthner cells. Understanding the neuronal circuits that control and regulate GA is central to understanding how motivated behaviors such as hunger, thirst and sexual behaviors arise.
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Comoli E, Das Neves Favaro P, Vautrelle N, Leriche M, Overton PG, Redgrave P. Segregated anatomical input to sub-regions of the rodent superior colliculus associated with approach and defense. Front Neuroanat 2012; 6:9. [PMID: 22514521 PMCID: PMC3324116 DOI: 10.3389/fnana.2012.00009] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 03/12/2012] [Indexed: 11/26/2022] Open
Abstract
The superior colliculus (SC) is responsible for sensorimotor transformations required to direct gaze toward or away from unexpected, biologically salient events. Significant changes in the external world are signaled to SC through primary multisensory afferents, spatially organized according to a retinotopic topography. For animals, where an unexpected event could indicate the presence of either predator or prey, early decisions to approach or avoid are particularly important. Rodents’ ecology dictates predators are most often detected initially as movements in upper visual field (mapped in medial SC), while appetitive stimuli are normally found in lower visual field (mapped in lateral SC). Our purpose was to exploit this functional segregation to reveal neural sites that can bias or modulate initial approach or avoidance responses. Small injections of Fluoro-Gold were made into medial or lateral sub-regions of intermediate and deep layers of SC (SCm/SCl). A remarkable segregation of input to these two functionally defined areas was found. (i) There were structures that projected only to SCm (e.g., specific cortical areas, lateral geniculate and suprageniculate thalamic nuclei, ventromedial and premammillary hypothalamic nuclei, and several brainstem areas) or SCl (e.g., primary somatosensory cortex representing upper body parts and vibrissae and parvicellular reticular nucleus in the brainstem). (ii) Other structures projected to both SCm and SCl but from topographically segregated populations of neurons (e.g., zona incerta and substantia nigra pars reticulata). (iii) There were a few brainstem areas in which retrogradely labeled neurons were spatially overlapping (e.g., pedunculopontine nucleus and locus coeruleus). These results indicate significantly more structures across the rat neuraxis are in a position to modulate defense responses evoked from SCm, and that neural mechanisms modulating SC-mediated defense or appetitive behavior are almost entirely segregated.
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Affiliation(s)
- Eliane Comoli
- Laboratory of Functional Neuroanatomy, Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo Ribeirão Preto, Brazil
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