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Ribeiro A, Gabriel R, Garcia B, Cuccio C, Aqeel W, Moreno A, Landeen C, Hurley A, Kavey N, Pfaff D. Temporal relations between peripheral and central arousals in good and poor sleepers. Proc Natl Acad Sci U S A 2022; 119:e2201143119. [PMID: 35696573 PMCID: PMC9231500 DOI: 10.1073/pnas.2201143119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/12/2022] [Indexed: 12/15/2022] Open
Abstract
Good sleepers and patients with insomnia symptoms (poor sleepers) were tracked with two measures of arousal; conventional polysomnography (PSG) for electroencephalogram (EEG) assessed cortical arousals, and a peripheral arterial tonometry device was used for the detection of peripheral nervous system (PNS) arousals associated with vasoconstrictions. The relationship between central (cortical) and peripheral (autonomic) arousals was examined by evaluating their close temporal dynamics. Cortical arousals almost invariably were preceded and followed by peripheral activations, while large peripheral autonomic arousals were followed by cortical arousals only half of the time. The temporal contiguity of these two types of arousals was altered in poor sleepers, and poor sleepers displayed a higher number of cortical and peripheral arousals compared with good sleepers. Given the difference in the number of peripheral autonomic arousals between good and poor sleepers, an evaluation of such arousals could become a means of physiologically distinguishing poor sleepers.
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Affiliation(s)
- Ana Ribeiro
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY 10065
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - Rachel Gabriel
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - Bernardo Garcia
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - Casey Cuccio
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - William Aqeel
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - Alejandro Moreno
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - Colby Landeen
- Division of Natural Sciences, College of Mount Saint Vincent, New York, NY 10471
| | - Arlene Hurley
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY 10065
| | - Neil Kavey
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY 10065
- Department of Psychiatry, Columbia University, New York, NY 10032
| | - Donald Pfaff
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY 10065
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2
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Ding T, Magarinos AM, Kow LM, Milner TA, Pfaff DW. Kv2.1 expression in giant reticular neurons of the postnatal mouse brain. J Chem Neuroanat 2021; 117:102005. [PMID: 34280489 PMCID: PMC8464498 DOI: 10.1016/j.jchemneu.2021.102005] [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: 04/24/2021] [Revised: 06/03/2021] [Accepted: 07/15/2021] [Indexed: 10/20/2022]
Abstract
Previous experiments charted the development of behavioral arousal in postnatal mice. From Postnatal Day 3 (P3) to Postnatal Day 6 (P6) mice (a) become significantly more active, "arousable"; and (b) in large reticular neurons, nucleus gigantocellularis (NGC), patch clamp recordings reveal a significantly increased ability to fire high frequency trains of action potentials as are associated with elevated cortical arousal. These action potential trains depend on delayed rectifiers such as Kv2.1. Here we report tracking the development of expression of a delayed rectifier, Kv2.1 in NGC neurons crucial for initiating CNS arousal. In tissue sections, light microscope immunohistochemistry revealed that expression of Kv2.1 in NGC neurons is greater at day P6 than at P3. Electron microscope immunohistochemistry revealed Kv2.1 labeling on the plasmalemmal surface of soma and dendrites, greater on P6 than P3. In brainstem reticular neuron cell culture, Kv2.1 immunocytochemistry increased monotonically from Days-In-Vitro 3-10, paralleling the ability of such neurons to fire action potential trains. The increase of Kv2.1 expression from P3 to P6, perhaps in conjunction with other delayed rectifier currents, could permit the ability to fire action potential trains in NGC neurons. Further work with genetically identified NGC neurons is indicated.
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Affiliation(s)
- Ting Ding
- Laboratory of Neurobiology and Behavior, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, United States; Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetrical and Gynecological Diseases, Tongji Medical College, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, 430030, China.
| | - Ana Maria Magarinos
- Laboratory of Neurobiology and Behavior, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, United States.
| | - Lee-Ming Kow
- Laboratory of Neurobiology and Behavior, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, United States.
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, 407 East 61st Street, New York, NY, 10065, United States; Harold and Milliken Hatch Laboratory of Neuroendocrinology, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, United States.
| | - Donald W Pfaff
- Laboratory of Neurobiology and Behavior, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, United States.
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3
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Potassium channels and the development of arousal-relevant action potential trains in primary hindbrain neurons. Brain Res 2021; 1768:147574. [PMID: 34274325 DOI: 10.1016/j.brainres.2021.147574] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/17/2021] [Accepted: 06/26/2021] [Indexed: 02/06/2023]
Abstract
Neurons in nucleus gigantocellularis (NGC) have been shown by many lines of evidence to be important for regulating generalized CNS arousal. Our previous study on mouse pups suggested that the development of NGC neurons' capability to fire action potential (AP) trains may both lead to the development of behavioral arousal and may itself depend on an increase in delayed rectifier currents. Here with whole-cell patch clamp we studied delayed rectifier currents in two stages. First, primary cultured neurons isolated from E12.5 embryonic hindbrain (HB), a dissection which contains all of NGC, were used to take advantage of studying neurons in vitro over using neurons in situ or in brain slices. HB neurons were tested with Guangxitoxin-1E and Resveratrol, two inhibitors of Kv2 channels which mediate the main bulk of delayed rectifier currents. Both inhibitors depressed delayed rectifier currents, but differentially: Resveratrol, but not Guangxitoxin-1E, reduced or abolished action potentials in AP trains. Since Resveratrol affects the Kv2.2 subtype, the development of the delayed rectifier mediated through Kv2.2 channels may lead to the development of HB neurons' capability to generate AP trains. Stage Two in this work found that electrophysiological properties of the primary HB neurons recorded are essentially the same as those of NGC neurons. Thus, from the two stages combined, we propose that currents mediated through Kv2.2 are crucial for generating AP trains which, in turn, lead to the development of mouse pup behavioral arousal.
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4
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Mueller SG, Muller AM. Brainstem Dysfunction in Healthy Aging. Neuroimage 2021; 238:118241. [PMID: 34116149 DOI: 10.1016/j.neuroimage.2021.118241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 04/29/2021] [Accepted: 06/04/2021] [Indexed: 11/16/2022] Open
Abstract
The brainstem controls sub-cortical and cortical activity and influences the processing of incoming information. The goal of this study was to characterize age related alterations of brainstem-brain interactions during different brain states detected by dynamic analysis of task-free fMRI. 79 young (20-40 years) and 51 older adults (55-80 years) were studied. Internal brainstem structures were segmented using a new multi-contrast segmentation approach. Brain and brainstem gray matter segmentations were warped onto a population template. The ICV-corrected Jacobian determinants were converted into z-score maps and the means from 420 cortical/subcortical/brainstem rois extracted. The fMRI was preprocessed in SPM12/Conn18 and the BOLD signal from 420 cortical/subcortical/brainstem rois extracted. A dynamic task-free analysis approach based on hierarchical cluster analysis was used to identify 15 brain states that were characterized using graph analysis (strength, diversity, modularity). Kruskal-Wallis tests and Spearman correlations were used for statistical analysis. One brain state (cluster 21) occurred more often in older adults (p=0.008). It was characterized by a lower mean modular strength and brainstem-cortical strength in older adults compared to younger adults. Global age related gray matter differences were positively correlated with brain state 21's modular strength. Furthermore, brain state 21 duration was negatively correlated with working memory (r = -0.28, p=0.002). The findings suggest an age related weakening of the within and between network synchronization at the brainstem level during brain state 21 in older adults that negatively affects cortical and subcortical synchronization and working memory performance.
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Affiliation(s)
- S G Mueller
- Dept. of Radiology, University of California, San Francisco, CA.
| | - A M Muller
- Dept. of Radiology, University of California, San Francisco, CA.
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5
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Kiiski H, Bennett M, Rueda-Delgado LM, Farina FR, Knight R, Boyle R, Roddy D, Grogan K, Bramham J, Kelly C, Whelan R. EEG spectral power, but not theta/beta ratio, is a neuromarker for adult ADHD. Eur J Neurosci 2020; 51:2095-2109. [PMID: 31834950 DOI: 10.1111/ejn.14645] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 12/05/2019] [Indexed: 12/14/2022]
Abstract
Adults with attention-deficit/hyperactivity disorder (ADHD) have been described as having altered resting-state electroencephalographic (EEG) spectral power and theta/beta ratio (TBR). However, a recent review (Pulini et al. 2018) identified methodological errors in neuroimaging, including EEG, ADHD classification studies. Therefore, the specific EEG neuromarkers of adult ADHD remain to be identified, as do the EEG characteristics that mediate between genes and behaviour (mediational endophenotypes). Resting-state eyes-open and eyes-closed EEG was measured from 38 adults with ADHD, 45 first-degree relatives of people with ADHD and 51 unrelated controls. A machine learning classification analysis using penalized logistic regression (Elastic Net) examined if EEG spectral power (1-45 Hz) and TBR could classify participants into ADHD, first-degree relatives and/or control groups. Random-label permutation was used to quantify any bias in the analysis. Eyes-open absolute and relative EEG power distinguished ADHD from control participants (area under receiver operating characteristic = 0.71-0.77). The best predictors of ADHD status were increased power in delta, theta and low-alpha over centro-parietal regions, and in frontal low-beta and parietal mid-beta. TBR did not successfully classify ADHD status. Elevated eyes-open power in delta, theta, low-alpha and low-beta distinguished first-degree relatives from controls (area under receiver operating characteristic = 0.68-0.72), suggesting that these features may be a mediational endophenotype for adult ADHD. Resting-state EEG spectral power may be a neuromarker and mediational endophenotype of adult ADHD. These results did not support TBR as a diagnostic neuromarker for ADHD. It is possible that TBR is a characteristic of childhood ADHD.
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Affiliation(s)
- Hanni Kiiski
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Marc Bennett
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,Medical Research Council- Cognition and Brain Sciences Unit, University of Cambridge, UK
| | | | - Francesca R Farina
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Rachel Knight
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Rory Boyle
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Darren Roddy
- Department of Psychiatry, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,Department of Physiology, School of Medicine, University College Dublin, Dublin, Ireland
| | - Katie Grogan
- UCD School of Psychology, University College Dublin, Dublin, Ireland
| | - Jessica Bramham
- UCD School of Psychology, University College Dublin, Dublin, Ireland
| | - Clare Kelly
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Robert Whelan
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland.,Global Brain Health Institute, Trinity College Dublin, Dublin, Ireland
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6
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Glover IS, Baker SN. Multimodal stimuli modulate rapid visual responses during reaching. J Neurophysiol 2019; 122:1894-1908. [DOI: 10.1152/jn.00158.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The reticulospinal tract plays an important role in primate upper limb function, but methods for assessing its activity are limited. One promising approach is to measure rapid visual responses (RVRs) in arm muscle activity during a visually cued reaching task; these may arise from a tecto-reticulospinal pathway. We investigated whether changes in reticulospinal excitability can be assessed noninvasively using RVRs, by pairing the visual stimuli of the reaching task with electrical stimulation of the median nerve, galvanic vestibular stimulation, or loud sounds, all of which are known to activate the reticular formation. Surface electromyogram (EMG) recordings were made from the right deltoid of healthy human subjects as they performed fast reaching movements toward visual targets. Stimuli were delivered up to 200 ms before target appearance, and RVR was quantified as the EMG amplitude in a window 75–125 ms after visual target onset. Median nerve, vestibular, and auditory stimuli all consistently facilitated the RVRs, as well as reducing the latency of responses. We propose that this facilitation reflects modulation of tecto-reticulospinal excitability, which is consistent with the idea that the amplitude of RVRs can be used to assess changes in brain stem excitability noninvasively in humans. NEW & NOTEWORTHY Short-latency responses in arm muscles evoked during a visually driven reaching task have previously been proposed to be tecto-reticulospinal in origin. We demonstrate that these responses can be facilitated by pairing the appearance of a visual target with stimuli that activate the reticular formation: median nerve, vestibular, and auditory stimuli. We propose that this reflects noninvasive measurement and modulation of reticulospinal excitability.
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Affiliation(s)
- Isabel S. Glover
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Stuart N. Baker
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
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7
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Laurens J, Angelaki DE. The Brain Compass: A Perspective on How Self-Motion Updates the Head Direction Cell Attractor. Neuron 2019; 97:275-289. [PMID: 29346751 DOI: 10.1016/j.neuron.2017.12.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 11/19/2017] [Accepted: 12/13/2017] [Indexed: 12/17/2022]
Abstract
Head direction cells form an internal compass signaling head azimuth orientation even without visual landmarks. This property is generated by a neuronal ring attractor that is updated using rotation velocity cues. The properties and origin of this velocity drive remain, however, unknown. We propose a quantitative framework whereby this drive represents a multisensory self-motion estimate computed through an internal model that uses sensory prediction errors of vestibular, visual, and somatosensory cues to improve on-line motor drive. We show how restraint-dependent strength of recurrent connections within the attractor can explain differences in head direction cell firing between free foraging and restrained passive rotation. We also summarize recent findings on how gravity influences azimuth coding, indicating that the velocity drive is not purely egocentric. Finally, we show that the internal compass may be three-dimensional and hypothesize that the additional vertical degrees of freedom use global allocentric gravity cues.
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Affiliation(s)
- Jean Laurens
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Dora E Angelaki
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
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8
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Molecular profiling of reticular gigantocellularis neurons indicates that eNOS modulates environmentally dependent levels of arousal. Proc Natl Acad Sci U S A 2018; 115:E6900-E6909. [PMID: 29967172 DOI: 10.1073/pnas.1806123115] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Neurons of the medullary reticular nucleus gigantocellularis (NGC) and their targets have recently been a focus of research on mechanisms supporting generalized CNS arousal (GA) required for proper cognitive functions. Using the retro-TRAP method, we characterized transcripts enriched in NGC neurons which have projections to the thalamus. The unique expression and activation of the endothelial nitric oxide (eNOS) signaling pathway in these cells and their intimate connections with blood vessels indicate that these neurons exert direct neurovascular coupling. Production of nitric oxide (NO) within eNOS-positive NGC neurons increases after environmental perturbations, indicating a role for eNOS/NO in modulating environmentally appropriate levels of GA. Inhibition of NO production causes dysregulated behavioral arousal after exposure to environmental perturbation. Further, our findings suggest interpretations for associations between psychiatric disorders and mutations in the eNOS locus.
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9
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Magariños AM, Pedron S, Creixell M, Kilinc M, Tabansky I, Pfaff DW, Harley BAC. The Feasibility of Encapsulated Embryonic Medullary Reticular Cells to Grow and Differentiate Into Neurons in Functionalized Gelatin-Based Hydrogels. FRONTIERS IN MATERIALS 2018; 5:40. [PMID: 30687706 PMCID: PMC6345411 DOI: 10.3389/fmats.2018.00040] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The study of the behavior of embryonic neurons in controlled in vitro conditions require methodologies that take advantage of advanced tissue engineering approaches to replicate elements of the developing brain extracellular matrix. We report here a series of experiments that explore the potential of photo-polymerized gelatin hydrogels to culture primary embryonic neurons. We employed large medullary reticular neurons whose activity is essential for brain arousal as well as a library of gelatin hydrogels that span a range of mechanical properties, inclusion of brain-mimetic hyaluronic acid, and adhesion peptides. These hydrogel platforms showed inherent capabilities to sustain neuronal viability and were permissive for neuronal differentiation, resulting in the development of neurite outgrowth under specific conditions. The maturation of embryonic medullary reticular cells took place in the absence of growth factors or other exogenous bioactive molecules. Immunocytochemistry labeling of neuron-specific tubulin confirmed the initiation of neural differentiation. Thus, this methodology provides an important validation for future studies of nerve cell growth and maintenance.
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Affiliation(s)
- Ana M. Magariños
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States
| | - Sara Pedron
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Marc Creixell
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States
| | - Murat Kilinc
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States
| | - Inna Tabansky
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States
| | - Donald W. Pfaff
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY, United States
| | - Brendan A. C. Harley
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States
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10
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Melo M, Gusso GDF, Levites M, Amaro E, Massad E, Lotufo PA, Zeidman P, Price CJ, Friston KJ. How doctors diagnose diseases and prescribe treatments: an fMRI study of diagnostic salience. Sci Rep 2017; 7:1304. [PMID: 28465538 PMCID: PMC5430984 DOI: 10.1038/s41598-017-01482-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 03/31/2017] [Indexed: 11/16/2022] Open
Abstract
Understanding the brain mechanisms involved in diagnostic reasoning may contribute to the development of methods that reduce errors in medical practice. In this study we identified similar brain systems for diagnosing diseases, prescribing treatments, and naming animals and objects using written information as stimuli. Employing time resolved modeling of blood oxygen level dependent (BOLD) responses enabled time resolved (400 milliseconds epochs) analyses. With this approach it was possible to study neural processes during successive stages of decision making. Our results showed that highly diagnostic information, reducing uncertainty about the diagnosis, decreased monitoring activity in the frontoparietal attentional network and may contribute to premature diagnostic closure, an important cause of diagnostic errors. We observed an unexpected and remarkable switch of BOLD activity within a right lateralized set of brain regions related to awareness and auditory monitoring at the point of responding. We propose that this neurophysiological response is the neural substrate of awareness of one’s own (verbal) response. Our results highlight the intimate relation between attentional mechanisms, uncertainty, and decision making and may assist the advance of approaches to prevent premature diagnostic closure.
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Affiliation(s)
- Marcio Melo
- Laboratory of Medical Investigations, LIM-01, Faculty of Medicine of the University of São Paulo, Av. Dr. Arnaldo 455, São Paulo, 01246-904, Brazil. .,Albert Einstein Israelite Hospital, IIEP, Av. Albert Einstein 627, São Paulo, 05652-900, Brazil.
| | - Gustavo D F Gusso
- Department of Internal Medicine, Faculty of Medicine of the University of São Paulo, Av. Dr. Eneas de Carvalho Aguiar 155, São Paulo, 05403-000, Brazil
| | - Marcelo Levites
- Department of Internal Medicine, Faculty of Medicine of the University of São Paulo, Av. Dr. Eneas de Carvalho Aguiar 155, São Paulo, 05403-000, Brazil
| | - Edson Amaro
- Albert Einstein Israelite Hospital, IIEP, Av. Albert Einstein 627, São Paulo, 05652-900, Brazil.,Department of Radiology, Faculty of Medicine of the University of São Paulo, Travessa da R. Dr. Ovídio Pires de Campos 75, São Paulo, 05403-010, Brazil
| | - Eduardo Massad
- Laboratory of Medical Investigations, LIM-01, Faculty of Medicine of the University of São Paulo, Av. Dr. Arnaldo 455, São Paulo, 01246-904, Brazil.,College of Life and Natural Sciences, University of Derby, Kedleston Road, Derby, KE22 1GB, United Kingdom
| | - Paulo A Lotufo
- Department of Internal Medicine, Faculty of Medicine of the University of São Paulo, Av. Dr. Eneas de Carvalho Aguiar 155, São Paulo, 05403-000, Brazil
| | - Peter Zeidman
- Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London, WC1N 3BG, United Kingdom
| | - Cathy J Price
- Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London, WC1N 3BG, United Kingdom
| | - Karl J Friston
- Wellcome Trust Centre for Neuroimaging, University College London, 12 Queen Square, London, WC1N 3BG, United Kingdom
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11
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Chen MC, Vetrivelan R, Guo CN, Chang C, Fuller PM, Lu J. Ventral medullary control of rapid eye movement sleep and atonia. Exp Neurol 2017; 290:53-62. [PMID: 28077261 DOI: 10.1016/j.expneurol.2017.01.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 12/24/2016] [Accepted: 01/04/2017] [Indexed: 11/27/2022]
Abstract
Discrete populations of neurons at multiple levels of the brainstem control rapid eye movement (REM) sleep and the accompanying loss of postural muscle tone, or atonia. The specific contributions of these brainstem cell populations to REM sleep control remains incompletely understood. Here we show in rats that viral vector-based lesions of the ventromedial medulla at a level rostral to the inferior olive (pSOM) produced violent myoclonic twitches and abnormal electromyographic spikes, but not complete loss of tonic atonia, during REM sleep. Motor tone during non-REM (NREM) sleep was unaffected in these same animals. Acute chemogenetic activation of pSOM neurons in rats robustly and selectively suppressed REM sleep but not NREM sleep. Similar lesions targeting the more rostral ventromedial medulla (RVM) did not affect sleep or atonia, while chemogenetic stimulation of the RVM produced wakefulness and reduced sleep. Finally, selective activation of vesicular GABA transporter (VGAT) pSOM neurons in mice produced complete suppression of REM sleep whereas their loss increased EMG spikes during REM sleep. These results reveal a key contribution of the pSOM and specifically the VGAT+ neurons in this region in REM sleep and motor control.
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Affiliation(s)
- Michael C Chen
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA 02115, USA
| | - Ramalingam Vetrivelan
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA 02115, USA
| | - Chun-Ni Guo
- Department of Neurology, Shanghai First People's Hospital Shanghai Jiaotong University, Shanghai, China
| | - Catie Chang
- Advanced Magnetic Resonance Imaging Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Patrick M Fuller
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA 02115, USA
| | - Jun Lu
- Beth Israel Deaconess Medical Center and Harvard Medical School, Department of Neurology, Division of Sleep Medicine, Boston, MA 02115, USA.
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12
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Liu X, Pfaff DW, Calderon DP, Tabansky I, Wang X, Wang Y, Kow LM. Development of Electrophysiological Properties of Nucleus Gigantocellularis Neurons Correlated with Increased CNS Arousal. Dev Neurosci 2016; 38:295-310. [PMID: 27788521 DOI: 10.1159/000449035] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/09/2016] [Indexed: 01/28/2023] Open
Abstract
Many types of data have suggested that neurons in the nucleus gigantocellularis (NGC) in the medullary reticular formation are critically important for CNS arousal and behavioral responsiveness. To extend this topic to a developmental framework, whole-cell patch-recorded characteristics of NGC neurons in brainstem slices and measures of arousal-dependent locomotion of postnatal day 3 (P3) to P6 mouse pups were measured and compared. These neuronal characteristics developed in an orderly, statistically significant monotonic manner over the course of P3-P6: (1) proportion of neurons capable of firing action potential (AP) trains, (2) AP amplitude, (3) AP threshold, (4) amplitude of inward and outward currents, (5) amplitude of negative peak currents, and (6) steady state currents (in I-V plot). These measurements reflect the maturation of sodium and certain potassium channels. Similarly, all measures of locomotion, latency to first movement, total locomotion duration, net locomotion distance, and total quiescence time also developed monotonically over P3-P6. Most importantly, electrophysiological and behavioral measures were significantly correlated. Interestingly, the behavioral measures were not correlated with frequency of excitatory postsynaptic currents or the proportion of neurons showing these currents, responses to a battery of neurotransmitter agents, or rapid activating potassium currents (including IA). Considering the results here in the context of a large body of literature on NGC, we hypothesize that the developmental increase in NGC neuronal excitability participates in causing the increased behavioral responsivity during the postnatal period from P3 to P6.
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Affiliation(s)
- Xu Liu
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, N.Y., USA
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13
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Calderon DP, Kilinc M, Maritan A, Banavar JR, Pfaff D. Generalized CNS arousal: An elementary force within the vertebrate nervous system. Neurosci Biobehav Rev 2016; 68:167-176. [PMID: 27216213 PMCID: PMC5003634 DOI: 10.1016/j.neubiorev.2016.05.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/19/2016] [Accepted: 05/19/2016] [Indexed: 01/13/2023]
Abstract
Why do animals and humans do anything at all? Arousal is the most powerful and essential function of the brain, a continuous function that accounts for the ability of animals and humans to respond to stimuli in the environment by producing muscular responses. Following decades of psychological, neurophysiological and molecular investigations, generalized CNS arousal can now be analyzed using approaches usually applied to physical systems. The concept of "criticality" is a state that illustrates an advantage for arousal systems poised near a phase transition. This property provides speed and sensitivity and facilitates the transition of the system into different brain states, especially as the brain crosses a phase transition from less aroused to more aroused states. In summary, concepts derived from applied mathematics of physical systems will now find their application in this area of neuroscience, the neurobiology of CNS arousal.
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Affiliation(s)
- D P Calderon
- Laboratory for Neurobiology and Behavior, the Rockefeller University, New York, NY 10065, United States; Department of Anaesthesiology, Weill Cornell Medical College, New York, NY 10021, United States.
| | - M Kilinc
- Laboratory for Neurobiology and Behavior, the Rockefeller University, New York, NY 10065, United States
| | - A Maritan
- Department of Physics, University of Padova, Istituto Nazionale di Fisica Nucleare and Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, 35131 Padova, Italy
| | - J R Banavar
- Department of Physics, University of Maryland, College Park, MD 20742, United States
| | - D Pfaff
- Laboratory for Neurobiology and Behavior, the Rockefeller University, New York, NY 10065, United States
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14
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Liang H, Wang S, Francis R, Whan R, Watson C, Paxinos G. Distribution of raphespinal fibers in the mouse spinal cord. Mol Pain 2015; 11:42. [PMID: 26173454 PMCID: PMC4502924 DOI: 10.1186/s12990-015-0046-x] [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: 04/18/2015] [Accepted: 07/03/2015] [Indexed: 12/13/2022] Open
Abstract
Background Serotonergic raphespinal neurons and their fibers have been mapped in large mammals, but the non-serotonergic ones have not been studied, especially in the mouse. The present study aimed to investigate the termination pattern of fibers arising from the hindbrain raphe and reticular nuclei which also have serotonergic neurons by injecting the anterograde tracer BDA into them. Results We found that raphespinal fibers terminate in both the dorsal and ventral horns in addition to lamina 10. There is a shift of the fibers in the ventral horn towards the dorsal and lateral part of the gray matter. Considerable variation in the termination pattern also exists between raphe nuclei with raphe magnus having more fibers terminating in the dorsal horn. Fibers from the adjacent gigantocellular reticular nucleus show similar termination pattern as those from the raphe nuclei with slight difference. Immunofluorescence staining showed that raphespinal fibers were heterogeneous and serotoninergic fibers were present in all laminae but mainly in laminae 1, 2, medial lamina 8, laminae 9 and 10. Surprisingly, immunofluorescence staining on clarified spinal cord tissue revealed that serotoninergic fibers formed bundles regularly in a short distance along the rostrocaudal axis in the medial part of the ventral horn and they extended towards the lateral motor neuron column area. Conclusion Serotonergic and non-serotonergic fibers arising from the hindbrain raphe and reticular nuclei had similar termination pattern in the mouse spinal cord with subtle difference. The present study provides anatomical foundation for the multiple roles raphe and adjacent reticular nuclei play. Electronic supplementary material The online version of this article (doi:10.1186/s12990-015-0046-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Huazheng Liang
- Neuroscience Research Australia, 139 Barker Street, Randwick, NSW, 2031, Australia. .,School of Medical Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia.
| | - Shaoshi Wang
- Department of Neurology, Branch of Shanghai First People's Hospital, Shanghai, 200081, China.
| | - Richard Francis
- Biomedical Imaging Facility, The University of New South Wales, Sydney, NSW, 2052, Australia.
| | - Renee Whan
- Biomedical Imaging Facility, The University of New South Wales, Sydney, NSW, 2052, Australia.
| | - Charles Watson
- Health Sciences Dean Research, Faculty of Health Sciences, Curtin University, Shenton Park Campus, Perth, WA, 6102, Australia.
| | - George Paxinos
- Neuroscience Research Australia, 139 Barker Street, Randwick, NSW, 2031, Australia. .,School of Medical Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia.
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15
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Bellesi M, Riedner BA, Garcia-Molina GN, Cirelli C, Tononi G. Enhancement of sleep slow waves: underlying mechanisms and practical consequences. Front Syst Neurosci 2014; 8:208. [PMID: 25389394 PMCID: PMC4211398 DOI: 10.3389/fnsys.2014.00208] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 10/02/2014] [Indexed: 02/06/2023] Open
Abstract
Even modest sleep restriction, especially the loss of sleep slow wave activity (SWA), is invariably associated with slower electroencephalogram (EEG) activity during wake, the occurrence of local sleep in an otherwise awake brain, and impaired performance due to cognitive and memory deficits. Recent studies not only confirm the beneficial role of sleep in memory consolidation, but also point to a specific role for sleep slow waves. Thus, the implementation of methods to enhance sleep slow waves without unwanted arousals or lightening of sleep could have significant practical implications. Here we first review the evidence that it is possible to enhance sleep slow waves in humans using transcranial direct-current stimulation (tDCS) and transcranial magnetic stimulation. Since these methods are currently impractical and their safety is questionable, especially for chronic long-term exposure, we then discuss novel data suggesting that it is possible to enhance slow waves using sensory stimuli. We consider the physiology of the K-complex (KC), a peripheral evoked slow wave, and show that, among different sensory modalities, acoustic stimulation is the most effective in increasing the magnitude of slow waves, likely through the activation of non-lemniscal ascending pathways to the thalamo-cortical system. In addition, we discuss how intensity and frequency of the acoustic stimuli, as well as exact timing and pattern of stimulation, affect sleep enhancement. Finally, we discuss automated algorithms that read the EEG and, in real-time, adjust the stimulation parameters in a closed-loop manner to obtain an increase in sleep slow waves and avoid undesirable arousals. In conclusion, while discussing the mechanisms that underlie the generation of sleep slow waves, we review the converging evidence showing that acoustic stimulation is safe and represents an ideal tool for slow wave sleep (SWS) enhancement.
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Affiliation(s)
- Michele Bellesi
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
| | - Brady A. Riedner
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
| | - Gary N. Garcia-Molina
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
- Clinical Sites Research Program, Philips Group InnovationBriarcliff, NY, USA
| | - Chiara Cirelli
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
| | - Giulio Tononi
- Department of Psychiatry, University of Wisconsin-MadisonMadison, WI, USA
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16
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Nickel F, Ott S, Möhringer S, Saake M, Dörfler A, Seifert F, Maihöfner C. Brain correlates of short-term habituation to repetitive electrical noxious stimulation. Eur J Pain 2013; 18:56-66. [DOI: 10.1002/j.1532-2149.2013.00339.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2013] [Indexed: 01/06/2023]
Affiliation(s)
- F.T. Nickel
- Department of Neurology; University of Erlangen-Nuremberg; Erlangen Germany
| | - S. Ott
- Department of Neurology; University of Erlangen-Nuremberg; Erlangen Germany
| | - S. Möhringer
- Department of Neurology; University of Erlangen-Nuremberg; Erlangen Germany
| | - M. Saake
- Department of Neuroradiology; University of Erlangen-Nuremberg; Erlangen Germany
| | - A. Dörfler
- Department of Neuroradiology; University of Erlangen-Nuremberg; Erlangen Germany
| | - F. Seifert
- Department of Neurology; University of Erlangen-Nuremberg; Erlangen Germany
| | - C. Maihöfner
- Department of Neurology; University of Erlangen-Nuremberg; Erlangen Germany
- Institute of Physiology and Experimental Pathophysiology; University of Erlangen-Nuremberg; Erlangen Germany
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17
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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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18
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Jankowska E, Nilsson E, Hammar I. Processing information related to centrally initiated locomotor and voluntary movements by feline spinocerebellar neurones. J Physiol 2011; 589:5709-25. [PMID: 21930605 DOI: 10.1113/jphysiol.2011.213678] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Feed-back information on centrally initiated movements is processed at both supraspinal and spinal levels and is forwarded by a variety of neurones. The aim of the present study was to examine how descending commands relayed by reticulospinal neurones are monitored by a population of spinocerebellar tract neurones. Our main question was whether a spinal border (SB) subpopulation of ventral spinocerebellar tract (VSCT) neurones monitor actions of reticulospinal neurones with input from the mesencephalic locomotor region (MLR) as well as from pyramidal tract (PT) neurones. In the majority of intracellularly recorded SB neurons, stimuli applied in the MLR and in the medullary pyramids evoked EPSPs in parallel with EPSPs evoked by stimulation of axons of reticulospinal neurones in the medial longitudinal fascicle (MLF). In extracellularly recorded neurones short trains of stimuli applied in the ipsilateral and contralateral pyramids potently facilitated discharges evoked from the MLF, as well as EPSPs recorded intracellularly. In both cases the facilitation involved the disynaptic but not the monosynaptic actions. These results indicate that reticulospinal neurones activating SB neurones (or more generally VSCT neurones) are co-excited by axon-collaterals of other reticulospinal neurones and by fibres stimulated within the MLR and PTs. The study leads to the conclusion that these spinocerebellar neurones monitor descending commands for centrally initiated voluntary as well as locomotor movements relayed by reticulospinal neurones. Thereby they may provide the cerebellum with feed-back information on the likely outcome of these commands and any corrections needed to avoid errors in the issuing movements.
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Affiliation(s)
- E Jankowska
- Department Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 405 30 Göteborg, Sweden.
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19
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Quinkert AW, Vimal V, Weil ZM, Reeke GN, Schiff ND, Banavar JR, Pfaff DW. Quantitative descriptions of generalized arousal, an elementary function of the vertebrate brain. Proc Natl Acad Sci U S A 2011; 108 Suppl 3:15617-23. [PMID: 21555568 PMCID: PMC3176607 DOI: 10.1073/pnas.1101894108] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We review a concept of the most primitive, fundamental function of the vertebrate CNS, generalized arousal (GA). Three independent lines of evidence indicate the existence of GA: statistical, genetic, and mechanistic. Here we ask, is this concept amenable to quantitative analysis? Answering in the affirmative, four quantitative approaches have proven useful: (i) factor analysis, (ii) information theory, (iii) deterministic chaos, and (iv) application of a Gaussian equation. It strikes us that, to date, not just one but at least four different quantitative approaches seem necessary for describing different aspects of scientific work on GA.
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Affiliation(s)
- Amy Wells Quinkert
- Laboratory of Neurobiology and Behavior and Laboratory of Biological Modelling, The Rockefeller University, New York, NY 10065, USA.
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20
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Martin EM, Devidze N, Shelley DN, Westberg L, Fontaine C, Pfaff DW. Molecular and neuroanatomical characterization of single neurons in the mouse medullary gigantocellular reticular nucleus. J Comp Neurol 2011; 519:2574-93. [PMID: 21456014 DOI: 10.1002/cne.22639] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Medullary gigantocellular reticular nucleus (mGi) neurons have been ascribed a variety of behaviors, many of which may fall under the concepts of either arousal or motivation. Despite this, many details of the connectivity of mGi neurons, particularly in reference to those neurons with ascending axons, remain unknown. To provide a neuroanatomical and molecular characterization of these cells, with reference to arousal and level-setting systems, large medullary reticular neurons were characterized with retrograde dye techniques and with real-time reverse transcriptase PCR (RT-PCR) analyses of single-neuron mRNA expression in the mouse. We have shown that receptors consistent with participation in generalized arousal are expressed by single mGi neurons and that receptors from different families of arousal-related neurotransmitters are rarely coexpressed. Through retrograde labeling, we have shown that neurons with ascending axons and neurons with descending axons tend to form like-with-like clusters, a finding that is consistent across age and gender. In comparing the two groups of retrogradely labeled neurons in neonatal animals, those neurons with axons that ascend to the midbrain show markers for GABAergic or coincident GABAergic and glutamatergic function; in contrast, approximately 60% of the neurons with axons that descend to the spinal cord are glutamatergic. We discuss the mGi's relationship to the voluntary and emotional motor systems and speculate that neurons in the mGi may represent a mammalian analogue to Mauthner cells, with a separation of function for neurons with ascending and descending axons.
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Affiliation(s)
- E M Martin
- Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, New York 10065, USA.
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21
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Schober J, Weil Z, Pfaff D. How generalized CNS arousal strengthens sexual arousal (and vice versa). Horm Behav 2011; 59:689-95. [PMID: 20950622 DOI: 10.1016/j.yhbeh.2010.10.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 09/23/2010] [Accepted: 10/02/2010] [Indexed: 12/22/2022]
Abstract
Heightened states of generalized CNS arousal are proposed here to facilitate sexual arousal in both males and females. Genetic, pharmacologic and biophysical mechanisms by which this happens are reviewed. Moreover, stimulation of the genital epithelia, as triggers of sex behavior, is hypothesized to lead to a greater generalized arousal in a manner that intensifies sexual motivation. Finally, launched from histochemical studies intended to characterize cells in the genital epithelium, a surprising idea is proposed that links density of innervation with the efficiency of wound healing and with the capacity of that epithelium to stimulate generalized CNS arousal. Thus, bidirectional arousal-related mechanisms that foster sexual behaviors are envisioned as follows: from specific to generalized (as with genital stimulation) and from generalized to specific.
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Affiliation(s)
- Justine Schober
- Laboratory of Neurobiology and Behavior, The Rockefeller University, NY, USA
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22
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23
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Abstract
Although there is an extensive amount known about specific sensory and motor functions of the vertebrate brain, less is understood about the regulation of global brain states. We have recently proposed that a function termed generalized arousal (Ag) serves as the most elemental driving force in the nervous system, responsible for the initial activation of all behavioral responses. An animal with increased generalized CNS arousal is characterized by greater motor activity, increased responsivity to sensory stimuli, and greater emotional lability. Implicit in this theory was the prediction that increases in generalized arousal would augment specific motivated behaviors that depend on arousal. Here, we address the idea directly by testing two lines of mice bred for high or low levels of generalized arousal and assessing their responses in tests of specific forms of behavioral arousal, sex and anxiety/exploration. We report that animals selected for differential generalized arousal exhibit marked increases in sensory, motor, and emotional reactivity in our arousal assay. Furthermore, male mice selected for high levels of generalized arousal were excitable and showed more incomplete mounts before the first intromission (IN), but having achieved that IN, they exhibited far fewer IN before ejaculating, as well as ejaculating much sooner after the first IN, thus indicating a high level of sexual arousal. Additionally, high-arousal animals of both sexes exhibited greater levels of anxiety-like behaviors and reduced exploratory behavior in the elevated plus maze and light-dark box tasks. Taken together, these data illustrate the impact of Ag on motivated behaviors.
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