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Toleikis JR, Pace C, Jahangiri FR, Hemmer LB, Toleikis SC. Intraoperative somatosensory evoked potential (SEP) monitoring: an updated position statement by the American Society of Neurophysiological Monitoring. J Clin Monit Comput 2024; 38:1003-1042. [PMID: 39068294 PMCID: PMC11427520 DOI: 10.1007/s10877-024-01201-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2024] [Accepted: 07/16/2024] [Indexed: 07/30/2024]
Abstract
Somatosensory evoked potentials (SEPs) are used to assess the functional status of somatosensory pathways during surgical procedures and can help protect patients' neurological integrity intraoperatively. This is a position statement on intraoperative SEP monitoring from the American Society of Neurophysiological Monitoring (ASNM) and updates prior ASNM position statements on SEPs from the years 2005 and 2010. This position statement is endorsed by ASNM and serves as an educational service to the neurophysiological community on the recommended use of SEPs as a neurophysiological monitoring tool. It presents the rationale for SEP utilization and its clinical applications. It also covers the relevant anatomy, technical methodology for setup and signal acquisition, signal interpretation, anesthesia and physiological considerations, and documentation and credentialing requirements to optimize SEP monitoring to aid in protecting the nervous system during surgery.
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Affiliation(s)
| | | | - Faisal R Jahangiri
- Global Innervation LLC, Dallas, TX, USA
- Department of Neuroscience, School of Behavioral and Brain Sciences, University of Texas at Dallas, Richardson, TX, USA
| | - Laura B Hemmer
- Anesthesiology and Neurological Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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Li W, Su C, Wang Z, Xu X, Zheng D. Cingulate sulcus sign: a descriptive analysis in a cerebral small vessel disease population. Front Aging Neurosci 2024; 16:1438796. [PMID: 39165838 PMCID: PMC11333361 DOI: 10.3389/fnagi.2024.1438796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Accepted: 07/22/2024] [Indexed: 08/22/2024] Open
Abstract
Objective The cingulate sulcus sign (CSS) has been observed in patients with idiopathic normal pressure hydrocephalus (iNPH), suggesting potential disruptions in cerebrospinal fluid circulation and compromised glymphatic system. Although there are similarities in the underlying mechanisms between cerebral small vessel disease (CSVD) and iNPH, the relationship between CSS and CSVD remains unclear. This study aimed to investigate the prevalence and potential mechanisms of CSS in patients with CSVD. Methods Data from patients diagnosed with CSVD at Shengjing Hospital of China Medical University between January 2020 and October 2022 were retrospectively collected, including general information, global cognitive function [assessed by measuring Mini-Mental State Examination (MMSE)], and four CSVD magnetic resonance imaging (MRI) markers [(white matter hyperintensity (WMH), cerebral microbleeds (CMBs), lacunes, and enlarged perivascular spaces (EPVS)], CSS and the Evan's index (EI). Results A total of 308 patients were included, and CSS was detected in 80 patients (26%). Univariate analysis revealed that MMSE scores in the CSS group were significantly lower compared to the non-CSS group (p < 0.001). Multivariable analysis showed an independent correlation between CSS and the presence of lacunes (odds ratio [OR] 0.358, 95% confidence interval [CI] 0.193-0.663, p = 0.001), presence of lobar dominant CMBs (OR 2.683, 95%CI 1.385-5.195, p = 0.003), periventricular WMH Fazekas score (OR 1.693, 95% CI 1.133-2.529, p = 0.01), and EI (OR 1.276, 95% CI 1.146-1.420, p < 0.001). Conclusion This preliminary study showed that CSS can be observed in some patients with CSVD. The presence of CSS may represent different mechanisms of CSVD pathogenesis and reflect differences in the degree of cerebrospinal fluid (CSF)/interstitial fluid (ISF) stasis.
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Affiliation(s)
| | | | | | | | - Dongming Zheng
- Department of Neurology, Shengjing Hospital of China Medical University, Shenyang, Liaoning, China
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Mahgoub R, Bayram AK, Spencer DD, Alkawadri R. Functional parcellation of the cingulate gyrus by electrical cortical stimulation: a synthetic literature review and future directions. J Neurol Neurosurg Psychiatry 2024; 95:704-721. [PMID: 38242679 DOI: 10.1136/jnnp-2023-332246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 12/30/2023] [Indexed: 01/21/2024]
Abstract
BACKGROUND The cingulate gyrus (CG), a brain structure above the corpus callosum, is recognised as part of the limbic system and plays numerous vital roles. However, its full functional capacity is yet to be understood. In recent years, emerging evidence from imaging modalities, supported by electrical cortical stimulation (ECS) findings, has improved our understanding. To our knowledge, there is a limited number of systematic reviews of the cingulate function studied by ECS. We aim to parcellate the CG by reviewing ECS studies. DESIGN/METHODS We searched PubMed and Embase for studies investigating CG using ECS. A total of 30 studies met the inclusion criteria. We evaluated the ECS responses across the cingulate subregions and summarised the reported findings. RESULTS We included 30 studies (totalling 887 patients, with a mean age of 31.8±9.8 years). The total number of electrodes implanted within the cingulate was 3028 electrode contacts; positive responses were obtained in 941 (31.1%, median percentages, 32.3%, IQR 22.2%-64.3%). The responses elicited from the CG were as follows. Simple motor (8 studies, 26.7 %), complex motor (10 studies, 33.3%), gelastic with and without mirth (7 studies, 23.3%), somatosensory (9 studies, 30%), autonomic (11 studies, 36.7 %), psychic (8 studies, 26.7%) and vestibular (3 studies, 10%). Visual and speech responses were also reported. Despite some overlap, the results indicate that the anterior cingulate cortex is responsible for most emotional, laughter and autonomic responses, while the middle cingulate cortex controls most complex motor behaviours, and the posterior cingulate cortex (PCC) regulates visual, among various other responses. Consistent null responses have been observed across different regions, emphasising PCC. CONCLUSIONS Our results provide a segmental mapping of the functional properties of CG, helping to improve precision in the surgical planning of epilepsy.
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Affiliation(s)
- Rawan Mahgoub
- Department of Neurology, The University of Pittsburgh Medical Center (UPMC), Pittsburgh, Pennsylvania, USA
| | - Ayse Kacar Bayram
- Department of Pediatrics, Division of Pediatric Neurology, University of Health Sciences, Kayseri City Hospital, Kayseri, Turkey
| | - Dennis D Spencer
- Department of Neurosurgery, Yale School of Medicine, New Haven, Connecticut, USA
| | - Rafeed Alkawadri
- Department of Neurology, The University of Pittsburgh Medical Center (UPMC), Pittsburgh, Pennsylvania, USA
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Marinkovic K, Woodruff D, White DR, Caudle MM, Cronan T. Neural indices of multimodal sensory and autonomic hyperexcitability in fibromyalgia. NEUROBIOLOGY OF PAIN (CAMBRIDGE, MASS.) 2023; 14:100140. [PMID: 38033709 PMCID: PMC10687342 DOI: 10.1016/j.ynpai.2023.100140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 07/21/2023] [Accepted: 07/21/2023] [Indexed: 12/02/2023]
Abstract
Fibromyalgia (FM) is characterized by chronic widespread musculoskeletal pain and psychological distress. Research suggests people with FM experience increased somatosensory sensitization which generalizes to other sensory modalities and may indicate neural hyperexcitability. However, the available evidence is limited, and studies including measures of neural responsivity across sensory domains and both central and peripheral aspects of the neuraxis are lacking. Thirty-nine participants (51.5 ± 13.6 years of age) with no history of neurological disorders, psychosis, visual, auditory, or learning deficits, were recruited for this study. People with FM (N = 19) and control participants (CNT, N = 20) did not differ on demographic variables and cognitive capacity. Participants completed a task that combined innocuous auditory stimuli with electrocutaneous stimulation (ECS), delivered at individually-selected levels that were uncomfortable but not painful. Event-related potentials (ERPs) and electrodermal activity were analyzed to examine the central and sympathetic indices of neural responsivity. FM participants reported greater sensitivity to ECS and auditory stimulation, as well as higher levels of depression, anxiety, ADHD, and an array of pain-related experiences than CNT. In response to ECS, the P50 deflection was greater in FM than CNT participants, reflecting early somatosensory hyperexcitability. The P50 amplitude was positively correlated with the FM profile factor obtained with a principal component analysis. The N100 to innocuous tones and sympathetic reactivity to ECS were greater in FM participants, except in the subgroup treated with gabapentinoids, which aligns with previous evidence of symptomatic improvement with GABA-mimetic medications. These results support the principal tenet of generalized neural hyperexcitability in FM and provide preliminary mechanistic insight into the impact of GABA-mimetic pharmacological therapy on ameliorating the neural excitation dominance.
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Affiliation(s)
- Ksenija Marinkovic
- Department of Psychology, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182, USA
- San Diego State University/University of California, San Diego, Joint Doctoral Program in Clinical Psychology, 5500 Campanile Dr., San Diego, CA 92182, USA
- Department of Radiology, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA
| | - Denali Woodruff
- Department of Psychology, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182, USA
| | - David R. White
- Department of Psychology, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182, USA
| | - Morgan M. Caudle
- Department of Psychology, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182, USA
- San Diego State University/University of California, San Diego, Joint Doctoral Program in Clinical Psychology, 5500 Campanile Dr., San Diego, CA 92182, USA
| | - Terry Cronan
- Department of Psychology, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182, USA
- San Diego State University/University of California, San Diego, Joint Doctoral Program in Clinical Psychology, 5500 Campanile Dr., San Diego, CA 92182, USA
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Ziogas A, Habermeyer E, Santtila P, Poeppl TB, Mokros A. Neuroelectric Correlates of Human Sexuality: A Review and Meta-Analysis. ARCHIVES OF SEXUAL BEHAVIOR 2023; 52:497-596. [PMID: 32016814 DOI: 10.1007/s10508-019-01547-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 07/17/2019] [Accepted: 09/04/2019] [Indexed: 05/15/2023]
Abstract
Many reviews on sexual arousal in humans focus on different brain imaging methods and behavioral observations. Although neurotransmission in the brain is mainly performed through electrochemical signals, there are no systematic reviews of the electrophysiological correlates of sexual arousal. We performed a systematic search on this subject and reviewed 255 studies including various electrophysiological methods. Our results show how neuroelectric signals have been used to investigate genital somatotopy as well as basic genital physiology during sexual arousal and how cortical electric signals have been recorded during orgasm. Moreover, experiments on the interactions of cognition and sexual arousal in healthy subjects and in individuals with abnormal sexual preferences were analyzed as well as case studies on sexual disturbances associated with diseases of the nervous system. In addition, 25 studies focusing on brain potentials during the interaction of cognition and sexual arousal were eligible for meta-analysis. The results showed significant effect sizes for specific brain potentials during sexual stimulation (P3: Cohen's d = 1.82, N = 300, LPP: Cohen's d = 2.30, N = 510) with high heterogeneity between the combined studies. Taken together, our review shows how neuroelectric methods can consistently differentiate sexual arousal from other emotional states.
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Affiliation(s)
- Anastasios Ziogas
- Department of Forensic Psychiatry, University Hospital of Psychiatry Zurich, Alleestrasse 61A, 8462, Rheinau, Switzerland.
| | - Elmar Habermeyer
- Department of Forensic Psychiatry, University Hospital of Psychiatry Zurich, Zurich, Switzerland
| | - Pekka Santtila
- Department of Arts & Sciences, New York University-Shanghai, Shanghai, China
| | - Timm B Poeppl
- Department of Psychiatry, Psychotherapy and Psychosomatic Medicine, RWTH Aachen University, Aachen, Germany
| | - Andreas Mokros
- Department of Forensic Psychiatry, University Hospital of Psychiatry Zurich, Zurich, Switzerland
- Faculty of Psychology, Fern Universität in Hagen (University of Hagen), Hagen, Germany
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Serrano-Amenos C, Heydari P, Liu CY, Do AH, Nenadic Z. Power Budget of a Skull Unit in a Fully-Implantable Brain-Computer Interface: Bio-Heat Model. IEEE Trans Neural Syst Rehabil Eng 2023; 31:4029-4039. [PMID: 37856256 DOI: 10.1109/tnsre.2023.3323916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
The aim of this study is to estimate the maximum power consumption that guarantees the thermal safety of a skull unit (SU). The SU is part of a fully-implantable bi-directional brain computer-interface (BD-BCI) system that aims to restore walking and leg sensation to those with spinal cord injury (SCI). To estimate the SU power budget, we created a bio-heat model using the finite element method (FEM) implemented in COMSOL. To ensure that our predictions were robust against the natural variation of the model's parameters, we also performed a sensitivity analysis. Based on our simulations, we estimated that the SU can nominally consume up to 70 mW of power without raising the surrounding tissues' temperature above the thermal safety threshold of 1°C. When considering the natural variation of the model's parameters, we estimated that the power budget could range between 47 and 81 mW. This power budget should be sufficient to power the basic operations of the SU, including amplification, serialization and A/D conversion of the neural signals, as well as control of cortical stimulation. Determining the power budget is an important specification for the design of the SU and, in turn, the design of a fully-implantable BD-BCI system.
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Stephani T, Nierula B, Villringer A, Eippert F, Nikulin VV. Cortical response variability is driven by local excitability changes with somatotopic organization. Neuroimage 2022; 264:119687. [PMID: 36257491 DOI: 10.1016/j.neuroimage.2022.119687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 09/23/2022] [Accepted: 10/14/2022] [Indexed: 11/09/2022] Open
Abstract
Identical sensory stimuli can lead to different neural responses depending on the instantaneous brain state. Specifically, neural excitability in sensory areas may shape the brain´s response already from earliest cortical processing onwards. However, whether these dynamics affect a given sensory domain as a whole or occur on a spatially local level is largely unknown. We studied this in the somatosensory domain of 38 human participants with EEG, presenting stimuli to the median and tibial nerves alternatingly, and testing the co-variation of initial cortical responses in hand and foot areas, as well as their relation to pre-stimulus oscillatory states. We found that amplitude fluctuations of initial cortical responses to hand and foot stimulation - the N20 and P40 components of the somatosensory evoked potential (SEP), respectively - were not related, indicating local excitability changes in primary sensory regions. In addition, effects of pre-stimulus alpha (8-13 Hz) and beta (18-23 Hz) band amplitude on hand-related responses showed a robust somatotopic organization, thus further strengthening the notion of local excitability fluctuations. However, for foot-related responses, the spatial specificity of pre-stimulus effects was less consistent across frequency bands, with beta appearing to be more foot-specific than alpha. Connectivity analyses in source space suggested this to be due to a somatosensory alpha rhythm that is primarily driven by activity in hand regions while beta frequencies may operate in a more hand-region-independent manner. Altogether, our findings suggest spatially distinct excitability dynamics within the primary somatosensory cortex, yet with the caveat that frequency-specific processes in one sub-region may not readily generalize to other sub-regions.
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Affiliation(s)
- T Stephani
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; International Max Planck Research School NeuroCom, Leipzig, Germany.
| | - B Nierula
- Max Planck Research Group Pain Perception, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - A Villringer
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany; Clinic for Cognitive Neurology, University Hospital Leipzig, Leipzig, Germany
| | - F Eippert
- Max Planck Research Group Pain Perception, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - V V Nikulin
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Neurophysics Group, Department of Neurology, Charité-Universitätsmedizin Berlin, Berlin, Germany; Bernstein Center for Computational Neuroscience, Berlin, Germany.
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8
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Sato S, Shibahara I, Inukai M, Komai H, Hide T, Kumabe T. Anatomical and neurophysiological localization of the leg motor area at the medial central sulcus. Clin Neurophysiol 2022; 143:67-74. [PMID: 36126357 DOI: 10.1016/j.clinph.2022.08.021] [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: 06/02/2022] [Revised: 08/01/2022] [Accepted: 08/24/2022] [Indexed: 11/03/2022]
Abstract
OBJECTIVE The exact location of the leg motor area is still in debate due to the lack of landmarks such as 'precentral knob' in the medial cortex. This study tried to identify the leg motor area based on intraoperative neurophysiological data and neuroimaging techniques. METHODS Intraoperative data of somatosensory evoked potential (SEP) elicited by tibial nerve stimulation and motor evoked potential (MEP) of the leg muscles induced by direct cortical stimulation were recorded using subdural electrodes placed in the medial cortex. We displayed the neurophysiological data on the individual MR images and the MNI52. RESULTS Definite N40-P40 phase reversal was observed with the shallow grooves in the medial cortex in 5 cases. Leg MEP was successfully obtained in all 12 cases preserving the leg motor function. Superimposed SEP and leg MEP data on the MNI152 indicated the leg motor area was predominantly located in the posterior two-thirds between the vertical lines passing through the anterior commissure and the posterior commissure (VCP). CONCLUSIONS Our study revealed the location of the leg motor area and the presence of the 'medial central sulcus' in the medial cortex. SIGNIFICANCE The VCP can be useful landmark to identify the sensorimotor border in the medial cortex.
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Affiliation(s)
- Sumito Sato
- Department of Neurosurgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
| | - Ichiyo Shibahara
- Department of Neurosurgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Madoka Inukai
- Department of Neurosurgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Hideto Komai
- Department of Neurosurgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Takuichiro Hide
- Department of Neurosurgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Toshihiro Kumabe
- Department of Neurosurgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
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Abstract
There are many recent advances in intraoperative evoked potential techniques for mapping and monitoring neural function during surgery. In particular, somatosensory evoked potential optimization speeds surgical feedback, motor evoked potentials provide selective motor system information, and new visual evoked potential methods promise reliable visual system monitoring. This chapter reviews these advances and provides a comprehensive background for understanding their context and importance.
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Affiliation(s)
| | - Charles C Dong
- Department of Surgery, University of British Columbia, Vancouver, BC, Canada
| | - Alberto Uribe
- Department of Anesthesiology, Ohio State University, Columbus, OH, United States
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Cortical interaction of bilateral inputs is similar for noxious and innocuous stimuli but leads to different perceptual effects. Exp Brain Res 2021; 239:2803-2819. [PMID: 34279670 DOI: 10.1007/s00221-021-06175-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/10/2021] [Indexed: 12/20/2022]
Abstract
The cerebral integration of somatosensory inputs from multiple sources is essential to produce adapted behaviors. Previous studies suggest that bilateral somatosensory inputs interact differently depending on stimulus characteristics, including their noxious nature. The aim of this study was to clarify how bilateral inputs evoked by noxious laser stimuli, noxious shocks, and innocuous shocks interact in terms of perception and brain responses. The experiment comprised two conditions (right-hand stimulation and concurrent stimulation of both hands) in which painful laser stimuli, painful shocks and non-painful shocks were delivered. Perception, somatosensory-evoked potentials (P45, N100, P260), laser-evoked potentials (N1, N2 and P2) and event-related spectral perturbations (delta to gamma oscillation power) were compared between conditions and stimulus modalities. The amplitude of negative vertex potentials (N2 or N100) and the power of delta/theta oscillations were increased in the bilateral compared with unilateral condition, regardless of the stimulus type (P < 0.01). However, gamma oscillation power increased for painful and non-painful shocks (P < 0.01), but not for painful laser stimuli (P = 0.08). Despite the similarities in terms of brain activity, bilateral inputs interacted differently for painful stimuli, for which perception remained unchanged, and non-painful stimuli, for which perception increased. This may reflect a ceiling effect for the attentional capture by noxious stimuli and warrants further investigations to examine the regulation of such interactions by bottom-up and top-down processes.
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Song Y, Su Q, Yang Q, Zhao R, Yin G, Qin W, Iannetti GD, Yu C, Liang M. Feedforward and feedback pathways of nociceptive and tactile processing in human somatosensory system: A study of dynamic causal modeling of fMRI data. Neuroimage 2021; 234:117957. [PMID: 33744457 DOI: 10.1016/j.neuroimage.2021.117957] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 03/07/2021] [Accepted: 03/09/2021] [Indexed: 11/30/2022] Open
Abstract
Nociceptive and tactile information is processed in the somatosensory system via reciprocal (i.e., feedforward and feedback) projections between the thalamus, the primary (S1) and secondary (S2) somatosensory cortices. The exact hierarchy of nociceptive and tactile information processing within this 'thalamus-S1-S2' network and whether the processing hierarchy differs between the two somatosensory submodalities remains unclear. In particular, two questions related to the ascending and descending pathways have not been addressed. For the ascending pathways, whether tactile or nociceptive information is processed in parallel (i.e., 'thalamus-S1' and 'thalamus-S2') or in serial (i.e., 'thalamus-S1-S2') remains controversial. For the descending pathways, how corticothalamic feedback regulates nociceptive and tactile processing also remains elusive. Here, we aimed to investigate the hierarchical organization for the processing of nociceptive and tactile information in the 'thalamus-S1-S2' network using dynamic causal modeling (DCM) combined with high-temporal-resolution fMRI. We found that, for both nociceptive and tactile information processing, both S1 and S2 received inputs from thalamus, indicating a parallel structure of ascending pathways for nociceptive and tactile information processing. Furthermore, we observed distinct corticothalamic feedback regulations from S1 and S2, showing that S1 generally exerts inhibitory feedback regulation independent of external stimulation whereas S2 provides additional inhibition to the thalamic activity during nociceptive and tactile information processing in humans. These findings revealed that nociceptive and tactile information processing have similar hierarchical organization within the somatosensory system in the human brain.
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Affiliation(s)
- Yingchao Song
- School of Medical Imaging and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University, Tianjin, China
| | - Qian Su
- Department of Molecular Imaging and Nuclear Medicine, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for China, Tianjin, China
| | - Qingqing Yang
- School of Medical Imaging and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University, Tianjin, China
| | - Rui Zhao
- School of Medical Imaging and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University, Tianjin, China; Department of Orthopedics Surgery, Tianjin Medical University General Hospital, Tianjin, China
| | - Guotao Yin
- Department of Molecular Imaging and Nuclear Medicine, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for China, Tianjin, China
| | - Wen Qin
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
| | - Gian Domenico Iannetti
- Neuroscience and Behaviour Laboratory, Italian Institute of Technology, Rome, Italy; Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Chunshui Yu
- Department of Radiology and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China; Chinese Academy of Sciences (CAS) Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Meng Liang
- School of Medical Imaging and Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University, Tianjin, China.
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Hand BJ, Opie GM, Sidhu SK, Semmler JG. TMS coil orientation and muscle activation influence lower limb intracortical excitability. Brain Res 2020; 1746:147027. [PMID: 32717277 DOI: 10.1016/j.brainres.2020.147027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/26/2020] [Accepted: 07/19/2020] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Previous research with transcranial magnetic stimulation (TMS) indicates that coil orientation (TMS current direction) and muscle activation state (rest or active) modify corticospinal and intracortical excitability of upper limb muscles. However, the extent to which these factors influence corticospinal and intracortical excitability of lower limb muscles is unknown. This study aimed to examine how variations in coil orientation and muscle activation affect corticospinal and intracortical excitability of tibialis anterior (TA), a lower leg muscle. METHODS In 21 young (21.6 ± 3.3 years, 11 female) adults, TMS was administered to the motor cortical representation of TA in posterior-anterior (PA) and mediolateral (ML) orientations at rest and during muscle activation. Single-pulse TMS measures of motor evoked potential amplitude, in addition to resting and active motor thresholds, were used to index corticospinal excitability, whereas paired-pulse TMS measures of short-interval intracortical inhibition (SICI) and facilitation (SICF), and long-interval intracortical inhibition (LICI), were used to assess excitability of intracortical circuits. RESULTS For single-pulse TMS, motor thresholds and test TMS intensity were lower for ML stimulation (all P < 0.05). In a resting muscle, ML TMS produced greater SICI (P < 0.001) and less SICF (both P < 0.05) when compared with PA TMS. In contrast, ML TMS in an active muscle resulted in reduced SICI but increased SICF (both P ≤ 0.001) when compared with PA TMS. CONCLUSION TMS coil orientation and muscle activation influence measurements of intracortical excitability recorded in the tibialis anterior, and are therefore important considerations in TMS studies of lower limb muscles.
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Affiliation(s)
- Brodie J Hand
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, Australia
| | - George M Opie
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, Australia
| | - Simranjit K Sidhu
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, Australia
| | - John G Semmler
- Discipline of Physiology, Adelaide Medical School, The University of Adelaide, Adelaide, Australia.
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Alt LK, Wach K, Liebler EJ, Straube A, Ruscheweyh R. A Randomized Sham-Controlled Cross-Over Study on the Short-Term Effect of Non-Invasive Cervical Vagus Nerve Stimulation on Spinal and Supraspinal Nociception in Healthy Subjects. Headache 2020; 60:1616-1631. [PMID: 32592516 DOI: 10.1111/head.13891] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/20/2020] [Accepted: 05/20/2020] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The aim of the present study was to test the effects of vagus nerve stimulation (VNS) on the descending pain inhibition, quantified by the nociceptive flexor (RIII) reflex and the conditioned pain modulation (CPM) paradigm, and on supraspinal nociceptive responses, assessed by pain intensity and unpleasantness ratings and late somatosensory evoked potentials (SEPs), in healthy subjects. BACKGROUND Non-invasive vagus nerve stimulation (nVNS) showed promising effects on headache and pain treatment. Underlying mechanisms are only incompletely understood but may include the activation of the descending pain inhibitory system and/or the modification of emotional responses to pain. METHODS Twenty-seven adult, healthy, and pain-free subjects participated in this double-blind cross-over study conducted at a university research center. They received 4 minutes of cervical nVNS or sham stimulation in randomized order. RIII reflexes, pain ratings, and SEPs were assessed before, during, and 5, 15, 30, and 60 minutes after nVNS/sham stimulation, followed by CPM testing. The primary outcome was the nVNS effect on the RIII reflex size. Three subjects were excluded after the preparatory session (before randomization), 1 subject was excluded after outlier analysis, leaving 23 for analysis. RESULTS RIII reflex areas were 917.1 ± 563.8 µV × ms (mean ± SD) before, 952.4 ± 467.4 µV × ms during and 929.2 ± 484.0 µV × ms immediately after nVNS and 858.4 ± 489.2 µV × ms before, 913.9 ± 539.7 µV × ms during and 862.4 ± 476.0 µV × ms after sham stimulation, revealing no differences between the immediate effects of nVNS and sham stimulation (F [3,66] = 0.67, P = .574). There also were no effects of nVNS over sham on RIII reflex areas up to 60 minutes after nVNS (F [1.7,37.4] = 1.29, P = .283). Similarly, there was no statistically significant effect of nVNS on pain intensity ratings and thresholds, RIII reflex thresholds, late SEP amplitudes, and the CPM effect, compared to sham. Pain unpleasantness ratings statistically significantly decreased from 4.4 ± 2.4 (NRS 0-10) to 4.1 ± 2.5 during nVNS compared to sham stimulation (F [1,22] = 8.74, P = .007), but there were no longer lasting effects (5-60 minutes after stimulation). CONCLUSIONS The present study does not support an acute effect of nVNS on descending pain inhibition, pain intensity perception or supraspinal nociception in healthy adults. However, there was a small effect on pain unpleasantness during nVNS, suggesting that nVNS may preferentially act on affective, not somatosensory pain components.
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Affiliation(s)
- Laura K Alt
- Department of Neurology, University of Munich, Munich, Germany
| | - Katharina Wach
- Department of Neurology, University of Munich, Munich, Germany
| | | | - Andreas Straube
- Department of Neurology, University of Munich, Munich, Germany.,Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany.,Research Training Group 2175, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
| | - Ruth Ruscheweyh
- Department of Neurology, University of Munich, Munich, Germany.,Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany.,Research Training Group 2175, Ludwig-Maximilians-University Munich, Planegg-Martinsried, Germany
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Intraoperative Electrophysiologic Mapping of Medial Frontal Motor Areas and Functional Outcomes. World Neurosurg 2020; 138:e389-e404. [DOI: 10.1016/j.wneu.2020.02.129] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 02/20/2020] [Accepted: 02/21/2020] [Indexed: 11/19/2022]
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15
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Single subject and group whole-brain fMRI mapping of male genital sensation at 7 Tesla. Sci Rep 2020; 10:2487. [PMID: 32051426 PMCID: PMC7015912 DOI: 10.1038/s41598-020-58966-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 01/13/2020] [Indexed: 01/07/2023] Open
Abstract
Processing of genital sensations in the central nervous system of humans is still poorly understood. Current knowledge is mainly based on neuroimaging studies using electroencephalography (EEG), magneto-encephalography (MEG), and 1.5- or 3- Tesla (T) functional magnetic resonance imaging (fMRI), all of which suffer from limited spatial resolution and sensitivity, thereby relying on group analyses to reveal significant data. Here, we studied the impact of passive, yet non-arousing, tactile stimulation of the penile shaft using ultra-high field 7T fMRI. With this approach, penile stimulation evoked significant activations in distinct areas of the primary and secondary somatosensory cortices (S1 & S2), premotor cortex, insula, midcingulate gyrus, prefrontal cortex, thalamus and cerebellum, both at single subject and group level. Passive tactile stimulation of the feet, studied for control, also evoked significant activation in S1, S2, insula, thalamus and cerebellum, but predominantly, yet not exclusively, in areas that could be segregated from those associated with penile stimulation. Evaluation of the whole-brain activation patterns and connectivity analyses indicate that genital sensations following passive stimulation are, unlike those following feet stimulation, processed in both sensorimotor and affective regions.
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Male Urogenital System Mapped Onto the Sensory Cortex: Functional Magnetic Resonance Imaging Evidence. J Sex Med 2020; 17:603-613. [PMID: 31953029 DOI: 10.1016/j.jsxm.2019.12.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 11/25/2019] [Accepted: 12/04/2019] [Indexed: 11/20/2022]
Abstract
INTRODUCTION The projection of the human male urogenital system onto the paracentral lobule has not previously been mapped comprehensively. AIM To map specific urogenital structures onto the primary somatosensory cortex toward a better understanding of sexual response in men. METHODS Using functional magnetic resonance imaging, we mapped primary somatosensory cortical responses to self-stimulation of the penis shaft, glans, testicles, scrotum, rectum, urethra, prostate, perineum, and nipple. We further compared neural response with erotic and prosaic touch of the penile shaft. MAIN OUTCOME MEASURE We identified the primary mapping site of urogenital structures on the paracentral lobule and identified networks involved in perceiving touch as erotic. RESULTS We mapped sites on the primary somatosensory cortex to which components of the urogenital structures project in men. Evidence is provided that penile cutaneous projection is different from deep penile projection. Similar to a prior report in women, we show that the nipple projects to the same somatosensory cortical region as the genitals. Evidence of differential representation of erotic and nonerotic genital self-stimulation is also provided, the former activating sensory networks other than the primary sensory cortex, indicating a role of "top-down" activity in erotic response. CLINICAL IMPLICATIONS We map primary sites of projection of urogenital structures to the primary somatosensory cortex and differentiate cortical sites of erotic from nonerotic genital self-stimulation. STRENGTH & LIMITATIONS To our knowledge, this is the first comprehensive mapping onto the primary somatosensory cortex of the projection of the components of the urogenital system in men and the difference in cortical activation in response to erotic vs nonerotic self-stimulation. The nipple was found to project to the same cortical region as the genitals. Evidence is provided that superficial and deep penile stimulation project differentially to the cortex, suggesting that sensory innervation of the penis is provided by more than the (pudendal) dorsal nerve. CONCLUSION This study reconciles prior apparently conflicting findings and offers a comprehensive mapping of male genital components to the paracentral lobule. We provide evidence of differential projection of light touch vs pressure applied to the penile shaft, suggesting differential innervation of its superficial, vs deep structure. Similar to the response in women, we found nipple projection to genital areas of the paracentral lobule. We also provide evidence of differential representation of erotic and nonerotic genital self-stimulation, the former activating sensory networks other than the primary sensory cortex, indicating a role of top-down activity in erotic response. Allen K, Wise N, Frangos E, et al. Male Urogenital System Mapped Onto the Sensory Cortex: Functional Magnetic Resonance Imaging Evidence. J Sex Med 2020;17:603-613.
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Lhomond O, Teasdale N, Simoneau M, Mouchnino L. Supplementary Motor Area and Superior Parietal Lobule Restore Sensory Facilitation Prior to Stepping When a Decrease of Afferent Inputs Occurs. Front Neurol 2019; 9:1132. [PMID: 30662426 PMCID: PMC6328453 DOI: 10.3389/fneur.2018.01132] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 12/10/2018] [Indexed: 12/22/2022] Open
Abstract
The weighting of the sensory inputs is not uniform during movement preparation and execution. For instance, a transient increase in the transmission to the cortical level of cutaneous input ~700 ms was observed before participants initiated a step forward. The sensory facilitation occurred at a time when feet cutaneous information is critical for setting the forces to be exerted onto the ground to shift the center of mass toward the supporting side prior to foot-off. Despite clear evidence of task-dependent modulation of the early somatosensory signal transmission, the neural mechanisms are mainly unknown. One hypothesis suggests that during movement preparation the premotor cortex and specifically the supplementary motor area (SMA) can be the source of an efferent signal that facilitates the somatosensory processes irrespectively of the amount of sensory inputs arriving at the somatosensory areas. Here, we depressed mechanically the plantar sole cutaneous transmission by increasing pressure under the feet by adding an extra body weight to test whether the task-dependent modulation is present during step preparation. Results showed upregulation of the neural response to tactile stimulation in the extra-weight condition during the stepping preparation whereas depressed neural response was still observed in standing condition. Source localization indicated the SMA and to a lesser extent the superior parietal lobule (SPL) areas as the likely origin of the response modulation. Upregulating cutaneous inputs (when mechanically depressed) at an early stage by efferent signals from the motor system could be an attempt to restore the level of sensory afferents to make it suitable for setting the anticipatory adjustments prior to step initiation.
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Affiliation(s)
- Olivia Lhomond
- Aix Marseille Univ, CNRS, Laboratoire de Neurosciences Cognitives, Marseille, France
| | - Normand Teasdale
- Faculté de médecine, Département de kinésiologie, Université Laval, Québec, QC, Canada
| | - Martin Simoneau
- Faculté de médecine, Département de kinésiologie, Université Laval, Québec, QC, Canada.,Centre Interdisciplinaire de Recherche en Réadaptation et Intégration Sociale, Québec, QC, Canada
| | - Laurence Mouchnino
- Aix Marseille Univ, CNRS, Laboratoire de Neurosciences Cognitives, Marseille, France
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Vakani R, Nair DR. Electrocorticography and functional mapping. HANDBOOK OF CLINICAL NEUROLOGY 2019; 160:313-327. [DOI: 10.1016/b978-0-444-64032-1.00020-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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19
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MacDonald D, Dong C, Quatrale R, Sala F, Skinner S, Soto F, Szelényi A. Recommendations of the International Society of Intraoperative Neurophysiology for intraoperative somatosensory evoked potentials. Clin Neurophysiol 2019; 130:161-179. [DOI: 10.1016/j.clinph.2018.10.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 09/27/2018] [Accepted: 10/21/2018] [Indexed: 11/25/2022]
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20
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Schwartz SL, Kale EB, Husain AM. Lower Extremity Somatosensory Evoked Potential P37 Waveform Optimization. Neurodiagn J 2018; 58:174-181. [PMID: 30257170 DOI: 10.1080/21646821.2018.1499304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Somatosensory evoked potentials (SEPs) using tibial nerve stimulation are used during neurophysiologic intraoperative monitoring (NIOM). These SEPs produce a P37 waveform that is recorded from scalp electrodes. In this study, we attempted to determine the best derivation for recording the P37 waveform. Surgical cases using tibial nerve SEP NIOM were reviewed. Only cases in which the P37 was recorded using all of the following derivations were analyzed: centroparietal ipsilateral-centroparietal contralateral (CPi-CPc), centroparietal midline-frontopolar midline (CPz-Fpz), and CPz-CPc. The amplitude of the P37 waveform was measured in each derivation. Descriptive statistics were obtained for the P37 waveform amplitude. The mean amplitude in each of the derivations was compared using a chi-square test. Data from 39 patients (78 lower limbs) were available for analysis. The mean age of the patients was 49.64 years (range: 4-87 years); 18 were female. The highest amplitude P37 waveform was recorded from the CPz-Fpz derivation in 29 (35.4%) limbs, whereas the CPz-CPc and CPi-CPc derivations showed the highest amplitude in 29 (35.4%) and 20 (24.4%) limbs, respectively. The mean amplitudes were not significantly different between the various derivations. In only 10 (24.4%) of patients was the best derivation the same for both left and right limbs. A single best derivation was not found for recording the P37 waveform. Multiple derivations should be used to record cortical channels whenever possible. If the number of available channels is limited, using at least the CPz-Fpz and CPz-CPc derivations is recommended.
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Affiliation(s)
- Stephanie L Schwartz
- a Neurodiagnostic Ancillary Services , Duke University Medical Center , Durham , North Carolina
| | - Emily B Kale
- a Neurodiagnostic Ancillary Services , Duke University Medical Center , Durham , North Carolina
| | - Aatif M Husain
- b Department of Neurology , Duke University Medical Center , Durham , North Carolina.,c Neurodiagnostic Center, Veterans Affairs Medical Center , Durham , North Carolina.,d Neuroscience Medicine, Duke Clinical Research Institute , Durham , North Carolina
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21
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Impact of non-brain anatomy and coil orientation on inter- and intra-subject variability in TMS at midline. Clin Neurophysiol 2018; 129:1873-1883. [PMID: 30005214 DOI: 10.1016/j.clinph.2018.04.749] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 03/11/2018] [Accepted: 04/16/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To investigate inter-subject variability with respect to cerebrospinal fluid thickness and brain-scalp distance, and to investigate intra-subject variability with different coil orientations. METHODS Simulations of the induced electric field (E-Field) using a figure-8 coil over the vertex were conducted on 50 unique head models and varying orientations on 25 models. Metrics exploring stimulation intensity, spread, and localization were used to describe inter-subject variability and effects of non-brain anatomy. RESULTS Both brain-scalp distance and CSF thickness were correlated with weaker stimulation intensity and greater spread. Coil rotations show that for the dorsal portion of the stimulated brain, E-Field intensities are highest when the anterior-posterior axis of the coil is perpendicular to the longitudinal fissure, but highest for the medial portion of the stimulated brain when the coil is oriented parallel to the longitudinal fissure. CONCLUSIONS Normal anatomical variation in healthy individuals leads to significant differences in the site of TMS, the intensity, and the spread. These variables are generally neglected but could explain significant variability in basic and clinical studies. SIGNIFICANCE This is the first work to show how brain-scalp distance and cerebrospinal fluid thickness influence focality, and to show the disassociation between dorsal and medial TMS.
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22
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Avanzini P, Pelliccia V, Lo Russo G, Orban GA, Rizzolatti G. Multiple time courses of somatosensory responses in human cortex. Neuroimage 2018; 169:212-226. [PMID: 29248698 PMCID: PMC5864517 DOI: 10.1016/j.neuroimage.2017.12.037] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 11/22/2017] [Accepted: 12/13/2017] [Indexed: 02/04/2023] Open
Abstract
Here we show how anatomical and functional data recorded from patients undergoing stereo-EEG can be used to decompose the cortical processing following nerve stimulation in different stages characterized by specific topography and time course. Tibial, median and trigeminal nerves were stimulated in 96 patients, and the increase in gamma power was evaluated over 11878 cortical sites. All three nerve datasets exhibited similar clusters of time courses: phasic, delayed/prolonged and tonic, which differed in topography, temporal organization and degree of spatial overlap. Strong phasic responses of the three nerves followed the classical somatotopic organization of SI, with no overlap in either time or space. Delayed responses presented overlaps between pairs of body parts in both time and space, and were confined to the dorsal motor cortices. Finally, tonic responses occurred in the perisylvian region including posterior insular cortex and were evoked by the stimulation of all three nerves, lacking any spatial and temporal specificity. These data indicate that the somatosensory processing following nerve stimulation is a multi-stage hierarchical process common to all three nerves, with the different stages likely subserving different functions. While phasic responses represent the neural basis of tactile perception, multi-nerve tonic responses may represent the neural signature of processes sustaining the capacity to become aware of tactile stimuli.
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Affiliation(s)
- P Avanzini
- Istituto di Neuroscienze, Consiglio nazionale delle Ricerche - CNR, Parma, Italy; Dipartimento di Medicina e Chirurgia, University of Parma, Italy.
| | - V Pelliccia
- Dipartimento di Medicina e Chirurgia, University of Parma, Italy; Centro per la chirurgia dell'Epilessia "Claudio Munari", Ospedale Ca'Granda-Niguarda, Milano, Italy
| | - G Lo Russo
- Centro per la chirurgia dell'Epilessia "Claudio Munari", Ospedale Ca'Granda-Niguarda, Milano, Italy
| | - G A Orban
- Dipartimento di Medicina e Chirurgia, University of Parma, Italy
| | - G Rizzolatti
- Istituto di Neuroscienze, Consiglio nazionale delle Ricerche - CNR, Parma, Italy; Dipartimento di Medicina e Chirurgia, University of Parma, Italy
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23
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Marshall CR, Hardy CJD, Russell LL, Clark CN, Bond RL, Dick KM, Brotherhood EV, Mummery CJ, Schott JM, Rohrer JD, Kilner JM, Warren JD. Motor signatures of emotional reactivity in frontotemporal dementia. Sci Rep 2018; 8:1030. [PMID: 29348485 PMCID: PMC5773553 DOI: 10.1038/s41598-018-19528-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 01/04/2018] [Indexed: 11/18/2022] Open
Abstract
Automatic motor mimicry is essential to the normal processing of perceived emotion, and disrupted automatic imitation might underpin socio-emotional deficits in neurodegenerative diseases, particularly the frontotemporal dementias. However, the pathophysiology of emotional reactivity in these diseases has not been elucidated. We studied facial electromyographic responses during emotion identification on viewing videos of dynamic facial expressions in 37 patients representing canonical frontotemporal dementia syndromes versus 21 healthy older individuals. Neuroanatomical associations of emotional expression identification accuracy and facial muscle reactivity were assessed using voxel-based morphometry. Controls showed characteristic profiles of automatic imitation, and this response predicted correct emotion identification. Automatic imitation was reduced in the behavioural and right temporal variant groups, while the normal coupling between imitation and correct identification was lost in the right temporal and semantic variant groups. Grey matter correlates of emotion identification and imitation were delineated within a distributed network including primary visual and motor, prefrontal, insular, anterior temporal and temporo-occipital junctional areas, with common involvement of supplementary motor cortex across syndromes. Impaired emotional mimesis may be a core mechanism of disordered emotional signal understanding and reactivity in frontotemporal dementia, with implications for the development of novel physiological biomarkers of socio-emotional dysfunction in these diseases.
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Affiliation(s)
- Charles R Marshall
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
| | - Chris J D Hardy
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Lucy L Russell
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Camilla N Clark
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Rebecca L Bond
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Katrina M Dick
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Emilie V Brotherhood
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Cath J Mummery
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Jonathan M Schott
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - James M Kilner
- Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
| | - Jason D Warren
- Dementia Research Centre, Department of Neurodegenerative Disease, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK
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Corticospinal excitability for hand muscles during motor imagery of foot changes with imagined force level. PLoS One 2017; 12:e0185547. [PMID: 28957398 PMCID: PMC5619792 DOI: 10.1371/journal.pone.0185547] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 09/14/2017] [Indexed: 11/19/2022] Open
Abstract
The object of this study was to clarify whether corticospinal excitability controlling hand muscles changes concurrently with increases in the imagined contraction level of foot dorsiflexion. Twelve participants performed actual and imagined dorsiflexion of their right foot at three different EMG levels (10, 40 or 80% of the maximum voluntary contraction). During isometric actual- or imagined- dorsiflexion, transcranial magnetic stimulation (TMS) was delivered to the right hand area of the left primary motor cortex. Motor evoked potentials (MEPs) were recorded from the right extensor carpi radialis (ECR) and flexor carpi radialis (FCR). During actual contraction, MEP amplitudes of ECR and FCR increased with an increased EMG level of dorsiflexion. Similarly, during imagery contraction, MEP amplitudes of ECR and FCR increased with the intensity of imagery contraction. Furthermore, a correlation between MEP amplitude during actual contraction and imagery contraction was observed for both ECR and FCR. Motor imagery of foot contraction induced an enhancement of corticospinal excitability for hand muscles that was dependent on the imagined contraction levels, just as what was observed when there was an actual contraction.
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Ettlin DA, Zhang H, Lutz K, Järmann T, Meier D, Gallo LM, Jäncke L, Palla S. Cortical Activation Resulting from Painless Vibrotactile Dental Stimulation Measured by Functional Magnetic Resonance Imaging (fMRI). J Dent Res 2016; 83:757-61. [PMID: 15381714 DOI: 10.1177/154405910408301004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
There have been few investigations on hemodynamic responses in the human cortex resulting from dental stimulation. Identification of cortical areas involved in stimulus perception may offer new targets for pain treatment. This initial study aimed at establishing a cortical map of dental representation, based on non-invasive fMRI measurements. Five right-handed subjects were studied. Eight maxillary and 8 mandibular teeth were stimulated after the vibratory perception threshold was determined for each tooth. Suprathreshold stimulation was repeated thrice per session, in a total of three sessions performed on three consecutive days. Statistical inference on cluster level identified increased blood-oxygen-level-dependent signal during vibratory dental stimulation, primarily in the insular cortex bilaterally and in the supplementary motor cortex. No significant brain activation was observed in the somatosensory cortex with this stimulation protocol. These results agree with previous findings obtained from invasive direct electrical cortical stimulation of the human insula.
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Affiliation(s)
- D A Ettlin
- Institute of Biomedical Engineering, ETH and University of Zürich, Switzerland.
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Chen W, Chang C, Hu Y. Single-Trial Extraction of Pure Somatosensory Evoked Potential Based on Expectation Maximization Approach. IEEE Trans Neural Syst Rehabil Eng 2016; 24:10-9. [PMID: 26742104 DOI: 10.1109/tnsre.2015.2432835] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
It is of great importance for intraoperative monitoring to accurately extract somatosensory evoked potentials (SEPs) and track its changes fast. Currently, multi-trial averaging is widely adopted for SEP signal extraction. However, because of the loss of variations related to SEP features across different trials, the estimated SEPs in such a way are not suitable for the purpose of real-time monitoring of every single trial of SEP. In order to handle this issue, a number of single-trial SEP extraction approaches have been developed in the literature, such as ARX and SOBI, but most of them have their performance limited due to not sufficient utilization of multi-trial and multi-condition structures of the signals. In this paper, a novel Bayesian model of SEP signals is proposed to make systemic use of multi-trial and multi-condition priors and other structural information in the signal by integrating both a cortical source propagation model and a SEP basis components model, and an Expectation Maximization (EM) algorithm is developed for single-trial SEP estimation under this model. Numerical simulations demonstrate that the developed method can provide reasonably good single-trial estimations of SEP as long as signal-to-noise ratio (SNR) of the measurements is no worse than -25 dB. The effectiveness of the proposed method is further verified by its application to real SEP measurements of a number of different subjects during spinal surgeries. It is observed that using the proposed approach the main SEP features (i.e., latencies) can be reliably estimated at single-trial basis, and thus the variation of latencies in different trials can be traced, which provides a solid support for surgical intraoperative monitoring.
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Sivaramakrishnan A, Tahara-Eckl L, Madhavan S. Spatial localization and distribution of the TMS-related 'hotspot' of the tibialis anterior muscle representation in the healthy and post-stroke motor cortex. Neurosci Lett 2016; 627:30-5. [PMID: 27222378 PMCID: PMC5111166 DOI: 10.1016/j.neulet.2016.05.041] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/10/2016] [Accepted: 05/20/2016] [Indexed: 10/21/2022]
Abstract
Transcranial magnetic stimulation (TMS) is a type of noninvasive brain stimulation used to study corticomotor excitability of the intact and injured brain. Identification of muscle representations in the motor cortex is typically done using a procedure called 'hotspotting', which involves establishing the optimal location on the scalp that evokes a maximum TMS response with minimum stimulator intensity. The purpose of this study was to report the hotspot locations for the tibialis anterior (TA) muscle representation in the motor cortex of healthy and post stroke individuals. A retrospective data analyses from 42 stroke participants and 32 healthy participants was conducted for reporting TMS hotspot locations and their spatial patterns. Single pulse TMS, using a 110mm double cone coil, was used to identify the motor representation of the TA. The hotspot locations were represented as x and y-distances from the vertex for each participant. The mediolateral extent of the loci from the vertex (x-coordinate) and anteroposterior extent of the loci from the vertex (y-coordinate) was reported for each hemisphere: non-lesioned (XNLes, YNLes), lesioned (XLes, YLes) and healthy (XH, YH). We found that the mean hotspot loci for TA muscle from the vertex were approximately: 1.29cm lateral and 0.55cm posterior in the non-lesioned hemisphere, 1.25cm lateral and 0.5cm posterior in the lesioned hemisphere and 1.6cm lateral and 0.8cm posterior in the healthy brain. There was no significant difference in the x- and y-coordinates between the lesioned and non-lesioned hemispheres. However, the locations of the XNLes (p=0.01) and XLes (p=0.004) were significantly different from XH. The YNLes and YLes showed no significant differences from YH loci. Analyses of spatial clustering patterns using the Moran's I index showed a negative autocorrelation in stroke participants (NLes: Moran's I=-0.09, p<0.001; Les: Moran's I=-0.14, p=0.002), and a positive autocorrelation in healthy participants (Moran's I=0.16, p<0.001), suggesting that individuals with stroke demonstrated a more dispersed pattern of hotspot locations than healthy individuals. Our results suggest that the hotspot loci show different spatial patterns in healthy and stroke individuals. The hotspot locations from this study has the potential to provide a guideline for optimal stimulation locations for the TA muscle in healthy and post stroke individuals for neuromodulation procedures such as transcranial direct current stimulation.
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Affiliation(s)
- Anjali Sivaramakrishnan
- Graduate Program in Rehabilitation Science, College of Applied Health Sciences, University of Illinois, Chicago, IL, USA
| | - Lenore Tahara-Eckl
- Department of Physical Therapy, College of Applied Health Sciences, University of Illinois, Chicago, IL, USA
| | - Sangeetha Madhavan
- Department of Physical Therapy, College of Applied Health Sciences, University of Illinois, Chicago, IL, USA.
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Zack M, Cho SS, Parlee J, Jacobs M, Li C, Boileau I, Strafella A. Effects of High Frequency Repeated Transcranial Magnetic Stimulation and Continuous Theta Burst Stimulation on Gambling Reinforcement, Delay Discounting, and Stroop Interference in Men with Pathological Gambling. Brain Stimul 2016; 9:867-875. [PMID: 27350401 DOI: 10.1016/j.brs.2016.06.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 05/30/2016] [Accepted: 06/11/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Repeated transcranial magnetic stimulation (rTMS) can reduce cravings and improve cognitive function in substance dependent individuals. Whether these benefits extend to individuals with pathological gambling (PG) is unclear. High-frequency rTMS of the medial prefrontal cortex (PFC) and continuous theta burst stimulation (cTBS) of the right dorsolateral PFC can reduce impulsive choice in healthy volunteers. OBJECTIVE This study aimed to assess the effects of these two protocols on gambling reinforcement and related responses in otherwise healthy men with PG. METHODS Participants (n = 9) underwent active or sham treatments at weekly intervals in a repeated-measures, Latin square design. Subjective and physiological responses were assessed before and after a 15-min slot machine game on each session. Delay discounting and Stroop tasks measured post-game impulsive choice and attentional control. RESULTS Multivariate analysis of covariance, controlling for winnings on the slot machine under each treatment, found that rTMS reduced the post-game increase in Desire to Gamble; cTBS reduced amphetamine-like effects, and decreased diastolic blood pressure. Treatment had no significant univariate effects on bet size or speed of play in the game; however, a multivariate effect for the two indices suggested that treatment decreased behavioral activation. Neither treatment reduced impulsive choice, while both treatments increased Stroop interference. CONCLUSIONS rTMS and cTBS can reduce gambling reinforcement in non-comorbid men with PG. Separate processes appear to mediate gambling reinforcement and betting behavior as against delay discounting and Stroop interference. Interventions that modify risky as opposed to temporal aspects of decision making may better predict therapeutic response in PG.
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Affiliation(s)
- Martin Zack
- Neuroscience Research Department, Centre for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario M5S 2S1, Canada.
| | - Sang Soo Cho
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T 1R8, Canada
| | - Jennifer Parlee
- Neuroscience Research Department, Centre for Addiction and Mental Health, 33 Russell Street, Toronto, Ontario M5S 2S1, Canada
| | - Mark Jacobs
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T 1R8, Canada
| | - Crystal Li
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T 1R8, Canada
| | - Isabelle Boileau
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T 1R8, Canada
| | - Antonio Strafella
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T 1R8, Canada
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Rambour M, Caux-Dedeystère A, Devanne H, Defebvre L, Derambure P, Delval A. Influence of repetitive transcranial magnetic stimulation on tibialis anterior activity during walking in humans. Neurosci Lett 2016; 616:49-56. [DOI: 10.1016/j.neulet.2016.01.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Revised: 01/13/2016] [Accepted: 01/16/2016] [Indexed: 12/01/2022]
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30
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Learned control over spinal nociception reduces supraspinal nociception as quantified by late somatosensory evoked potentials. Pain 2015; 156:2505-2513. [DOI: 10.1097/j.pain.0000000000000327] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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31
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Boccard SGJ, Fernandes HM, Jbabdi S, Van Hartevelt TJ, Kringelbach ML, Quaghebeur G, Moir L, Mancebo VP, Pereira EAC, Fitzgerald JJ, Green AL, Stein J, Aziz TZ. Tractography Study of Deep Brain Stimulation of the Anterior Cingulate Cortex in Chronic Pain: Key to Improve the Targeting. World Neurosurg 2015; 86:361-70.e1-3. [PMID: 26344354 DOI: 10.1016/j.wneu.2015.08.065] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/28/2015] [Accepted: 08/29/2015] [Indexed: 12/14/2022]
Abstract
BACKGROUND Deep brain stimulation (DBS) of the anterior cingulate cortex (ACC) is a new treatment for alleviating intractable neuropathic pain. However, it fails to help some patients. The large size of the ACC and the intersubject variability make it difficult to determine the optimal site to position DBS electrodes. The aim of this work was therefore to compare the ACC connectivity of patients with successful versus unsuccessful DBS outcomes to help guide future electrode placement. METHODS Diffusion magnetic resonance imaging (dMRI) and probabilistic tractography were performed preoperatively in 8 chronic pain patients (age 53.4 ± 6.1 years, 2 females) with ACC DBS, of whom 6 had successful (SO) and 2 unsuccessful outcomes (UOs) during a period of trialing. RESULTS The number of patients was too small to demonstrate any statistically significant differences. Nevertheless, we observed differences between patients with successful and unsuccessful outcomes in the fiber tract projections emanating from the volume of activated tissue around the electrodes. A strong connectivity to the precuneus area seems to predict unsuccessful outcomes in our patients (UO: 160n/SO: 27n), with (n), the number of streamlines per nonzero voxel. On the other hand, connectivity to the thalamus and brainstem through the medial forebrain bundle (MFB) was only observed in SO patients. CONCLUSIONS These findings could help improve presurgical planning by optimizing electrode placement, to selectively target the tracts that help to relieve patients' pain and to avoid those leading to unwanted effects.
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Affiliation(s)
- Sandra G J Boccard
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom.
| | - Henrique M Fernandes
- Department of Psychiatry, University of Oxford, United Kingdom; CFIN/MindLab, Aarhus University, Aarhus, Denmark
| | - Saad Jbabdi
- Centre for Functional MRI of the Brain (FMRIB), University of Oxford, United Kingdom
| | - Tim J Van Hartevelt
- Department of Psychiatry, University of Oxford, United Kingdom; CFIN/MindLab, Aarhus University, Aarhus, Denmark
| | - Morten L Kringelbach
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom; Department of Psychiatry, University of Oxford, United Kingdom; CFIN/MindLab, Aarhus University, Aarhus, Denmark
| | | | - Liz Moir
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom
| | - Victor Piqueras Mancebo
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom
| | - Erlick A C Pereira
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom
| | - James J Fitzgerald
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom
| | - Alexander L Green
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom
| | - John Stein
- Department of Physiology, Anatomy, & Genetics, University of Oxford, United Kingdom
| | - Tipu Z Aziz
- Oxford Functional Neurosurgery and Experimental Neurology Group, Nuffield Departments of Clinical Neuroscience and Surgery, University of Oxford, United Kingdom
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Cazala F, Vienney N, Stoléru S. The cortical sensory representation of genitalia in women and men: a systematic review. SOCIOAFFECTIVE NEUROSCIENCE & PSYCHOLOGY 2015; 5:26428. [PMID: 25766001 PMCID: PMC4357265 DOI: 10.3402/snp.v5.26428] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 01/10/2015] [Accepted: 01/10/2015] [Indexed: 12/20/2022]
Abstract
Background Although genital sensations are an essential aspect of sexual behavior, the cortical somatosensory representation of genitalia in women and men remain poorly known and contradictory results have been reported. Objective To conduct a systematic review of studies based on electrophysiological and functional neuroimaging studies, with the aim to identify insights brought by modern methods since the early descriptions of the sensory homunculus in the primary somatosensory cortex (SI). Results The review supports the interpretation that there are two distinct representations of genital sensations in SI, one on the medial surface and the other on the lateral surface. In addition, the review suggests that the secondary somatosensory cortex and the posterior insula support a representation of the affective aspects of genital sensation. Conclusion In view of the erogenous character of sensations originating in the genitalia, future studies on this topic should systematically assess qualitatively as well as quantitatively the sexually stimulating and/or sexually pleasurable characteristics of sensations felt by subjects in response to experimental stimuli.
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Affiliation(s)
- Fadwa Cazala
- INSERM U669, Université Paris Descartes, Paris, France
| | | | - Serge Stoléru
- INSERM U669, Université Paris Descartes, Paris, France;
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Georgiadis JR. Functional neuroanatomy of human cortex cerebri in relation to wanting sex and having it. Clin Anat 2015; 28:314-23. [DOI: 10.1002/ca.22528] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 01/27/2015] [Indexed: 12/29/2022]
Affiliation(s)
- Janniko R. Georgiadis
- Department of Neuroscience/Section Anatomy; University Medical Center Groningen (UMCG), University of Groningen; The Netherlands
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Cho SS, Koshimori Y, Aminian K, Obeso I, Rusjan P, Lang AE, Daskalakis ZJ, Houle S, Strafella AP. Investing in the future: stimulation of the medial prefrontal cortex reduces discounting of delayed rewards. Neuropsychopharmacology 2015; 40:546-53. [PMID: 25168685 PMCID: PMC4289950 DOI: 10.1038/npp.2014.211] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/15/2014] [Accepted: 08/02/2014] [Indexed: 11/09/2022]
Abstract
Generally, rewards that are received sooner are often preferred over future rewards, and the time between the choice and the reception of the reward is an important factor that influences our decisions, a phenomenon called delay discounting (DD). In DD, the medial prefrontal cortex (MePFC) and striatal dopamine neurotransmission both play an important role. We used repetitive transcranial magnetic stimulation (rTMS) to transiently activate the MePFC to evaluate its behavioral effect on the DD paradigm, and subsequently to measure its effect on striatal dopamine. Twenty-four right-handed young healthy subjects (11 females; age: 22.1±2.9 years) underwent DD following 10 Hz-rTMS of the MePFC and vertex stimulation (control condition). Thereafter, 11 subjects (5 females; age: 22.2±2.87 years) completed the PET study at rest using [(11)C]-(+)-PHNO following 10 Hz-rTMS of the MePFC and vertex. Modulation of the MePFC excitability influenced the subjective level of DD for delayed rewards and interfered with synaptic dopamine level in the striatum. The present study yielded findings that might reconcile the role of these areas in inter-temporal decision making and dopamine modulation, suggesting that the subjective sense of time and value of reward are critically controlled by these important regions.
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Affiliation(s)
- Sang Soo Cho
- Division of Brain, Imaging and Behaviour—Systems Neuroscience, Toronto Western Research Institute, UHN, University of Toronto, Ontario, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Yuko Koshimori
- Division of Brain, Imaging and Behaviour—Systems Neuroscience, Toronto Western Research Institute, UHN, University of Toronto, Ontario, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Kelly Aminian
- Division of Brain, Imaging and Behaviour—Systems Neuroscience, Toronto Western Research Institute, UHN, University of Toronto, Ontario, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Ignacio Obeso
- Division of Brain, Imaging and Behaviour—Systems Neuroscience, Toronto Western Research Institute, UHN, University of Toronto, Ontario, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Pablo Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Anthony E Lang
- Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, ON, Canada
| | - Zafiris J Daskalakis
- Temerty Centre for Therapeutic Brain Intervention, Department of Psychiatry, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Sylvain Houle
- Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada
| | - Antonio P Strafella
- Division of Brain, Imaging and Behaviour—Systems Neuroscience, Toronto Western Research Institute, UHN, University of Toronto, Ontario, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, University of Toronto, ON, Canada,Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Toronto Western Hospital, UHN, University of Toronto, ON, Canada,Toronto Western Hospital and Institute, CAMH-Research Imaging Centre, University of Toronto, Toronto, ON, M5T 2S8, Canada, Tel: +416 535 8501 ext 7394, E-mail: or
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35
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Abnormal cerebellar volume and corticocerebellar dysfunction in early manifest Huntington’s disease. J Neurol 2015; 262:859-69. [DOI: 10.1007/s00415-015-7642-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 11/27/2022]
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Nakanishi K, Inoue K, Hadoush H, Sunagawa T, Ochi M. Dipole orientation of receptive fields in the somatosensory cortex after stimulation of the posterior tibial nerve in humans. J Clin Neurophysiol 2015; 31:236-40. [PMID: 24887607 DOI: 10.1097/wnp.0000000000000044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The origins of the earliest evoked potentials and magnetic fields after tibial nerve electrical stimulation are still controversial. We focused on the initial activity from the gyrus area and analyzed the components for the coronal and sagittal planes. In 12 healthy right-handed subjects, electrical stimuli were delivered to the left posterior tibial nerve at the ankle. The cortical somatosensory evoked fields were recorded, and the equivalent current dipoles were calculated and separated into the sagittal plane (y-components) and coronal plane (x-components) components. In nine subjects, we observed two deflections (y1 and y2) in the y-component waveform and two deflections (x1 and x2) in the x-component waveform over 60 milliseconds; y1 was directed anteriorly, y2 posteriorly, x1 to the left, and x2 to the right. The y1 was originated in the anterior wall of the central sulcus. By focusing on the y-component, we elucidated the existence of the posteroanterior component, which may originate from the area 3b (gyrus) in tibial nerve somatosensory evoked fields and has the same quality as N20m for median nerve somatosensory evoked fields. This is the first report to suggest that the posteroanterior component in the tibial nerve is analogous to N20m in the median nerve using magnetoencephalography.
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Affiliation(s)
- Kazuyoshi Nakanishi
- *Department of Orthopaedic Surgery, Programs for Applied Biomedicine, Division of Clinical Medical Science, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan; †Department of Neurology, Hiroshima Prefectural Hospital, Hiroshima, Japan; ‡Graduate School of Health Science, Hiroshima University, Hiroshima, Japan; and §Faculty of Applied Medical Sciences, Jordan University of Science & Technology, Irbid, Jordan
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Motor cortex activation by H-coil and figure-8 coil at different depths. Combined motor threshold and electric field distribution study. Clin Neurophysiol 2014; 125:336-43. [DOI: 10.1016/j.clinph.2013.07.013] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/24/2013] [Accepted: 07/28/2013] [Indexed: 11/19/2022]
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Cattaneo L, Pavesi G. The facial motor system. Neurosci Biobehav Rev 2013; 38:135-59. [PMID: 24239732 DOI: 10.1016/j.neubiorev.2013.11.002] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 10/18/2013] [Accepted: 11/02/2013] [Indexed: 12/23/2022]
Abstract
Facial movements support a variety of functions in human behavior. They participate in automatic somatic and visceral motor programs, they are essential in producing communicative displays of affective states and they are also subject to voluntary control. The multiplicity of functions of facial muscles, compared to limb muscles, is reflected in the heterogeneity of their anatomical and histological characteristics that goes well beyond the conventional classification in single facial muscles. Such parcellation in different functional muscular units is maintained throughout the central representation of facial movements from the brainstem up to the neocortex. Facial movements peculiarly lack a conventional proprioceptive feedback system, which is only in part vicariated by cutaneous or auditory afferents. Facial motor activity is the main marker of endogenous affective states and of the affective valence of external stimuli. At the cortical level, a complex network of specialized motor areas supports voluntary facial movements and, differently from upper limb movements, in such network there does not seem to be a prime actor in the primary motor cortex.
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Affiliation(s)
- Luigi Cattaneo
- Center for Mind/Brain Sciences, University of Trento, Via delle Regole 101, Mattarello, Trento 38123, Italy.
| | - Giovanni Pavesi
- Department of Neuroscience, University of Parma, Via Gramsci 14, Parma 43100, Italy
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de Zubicaray G, Arciuli J, McMahon K. Putting an “End” to the Motor Cortex Representations of Action Words. J Cogn Neurosci 2013; 25:1957-74. [DOI: 10.1162/jocn_a_00437] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Abstract
Language processing is an example of implicit learning of multiple statistical cues that provide probabilistic information regarding word structure and use. Much of the current debate about language embodiment is devoted to how action words are represented in the brain, with motor cortex activity evoked by these words assumed to selectively reflect conceptual content and/or its simulation. We investigated whether motor cortex activity evoked by manual action words (e.g., caress) might reflect sensitivity to probabilistic orthographic–phonological cues to grammatical category embedded within individual words. We first review neuroimaging data demonstrating that nonwords evoke activity much more reliably than action words along the entire motor strip, encompassing regions proposed to be action category specific. Using fMRI, we found that disyllabic words denoting manual actions evoked increased motor cortex activity compared with non-body-part-related words (e.g., canyon), activity which overlaps that evoked by observing and executing hand movements. This result is typically interpreted in support of language embodiment. Crucially, we also found that disyllabic nonwords containing endings with probabilistic cues predictive of verb status (e.g., -eve) evoked increased activity compared with nonwords with endings predictive of noun status (e.g., -age) in the identical motor area. Thus, motor cortex responses to action words cannot be assumed to selectively reflect conceptual content and/or its simulation. Our results clearly demonstrate motor cortex activity reflects implicit processing of ortho-phonological statistical regularities that help to distinguish a word's grammatical class.
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Affiliation(s)
| | | | - Katie McMahon
- 3University of Queensland, Centre for Advanced Imaging
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40
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Kato K, Muraoka T, Higuchi T, Mizuguchi N, Kanosue K. Interaction between simultaneous contraction and relaxation in different limbs. Exp Brain Res 2013; 232:181-9. [DOI: 10.1007/s00221-013-3730-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 10/01/2013] [Indexed: 10/26/2022]
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Richter L, Neumann G, Oung S, Schweikard A, Trillenberg P. Optimal coil orientation for transcranial magnetic stimulation. PLoS One 2013; 8:e60358. [PMID: 23593200 PMCID: PMC3623976 DOI: 10.1371/journal.pone.0060358] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 02/26/2013] [Indexed: 01/21/2023] Open
Abstract
We study the impact of coil orientation on the motor threshold (MT) and present an optimal coil orientation for stimulation of the foot. The result can be compared to results of models that predict this orientation from electrodynamic properties of the media in the skull and from orientations of cells, respectively. We used a robotized TMS system for precise coil placement and recorded motor-evoked potentials with surface electrodes on the abductor hallucis muscle of the right foot in 8 healthy control subjects. First, we performed a hot-spot search in standard (lateral) orientation and then rotated the coil in steps of 10° or 20°. At each step we estimated the MT. For navigated stimulation and for correlation with the underlying anatomy a structural MRI scan was obtained. Optimal coil orientation was 33.1±18.3° anteriorly in relation to the standard lateral orientation. In this orientation the threshold was 54±18% in units of maximum stimulator output. There was a significant difference of 8.0±5.9% between the MTs at optimal and at standard orientation. The optimal coil orientations were significantly correlated with the direction perpendicular to the postcentral gyrus (). Robotized TMS facilitates sufficiently precise coil positioning and orientation to study even small variations of the MT with coil orientation. The deviations from standard orientation are more closely matched by models based on field propagation in media than by models based on orientations of pyramidal cells.
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Affiliation(s)
- Lars Richter
- Institute for Robotics and Cognitive Systems, University of Lübeck, Lübeck, Germany.
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Trillenberg P, Bremer S, Oung S, Erdmann C, Schweikard A, Richter L. Variation of stimulation intensity in transcranial magnetic stimulation with depth. J Neurosci Methods 2012; 211:185-90. [DOI: 10.1016/j.jneumeth.2012.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 08/28/2012] [Accepted: 09/04/2012] [Indexed: 01/20/2023]
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Boord P, Barriskill A, Craig A, Nguyen H. Brain-Computer Interface-FES Integration: Towards a Hands-free Neuroprosthesis Command System. Neuromodulation 2012; 7:267-76. [PMID: 22151336 DOI: 10.1111/j.1094-7159.2004.04212.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This paper presents a critical review of brain-computer interfaces (BCIs) and their potential for neuroprosthetic applications. Summaries are provided for the command interface requirements of hand grasp, multijoint, and lower extremity neuroprostheses, and the characteristics of various BCIs are discussed in relation to these requirements. The review highlights the current limitations of BCIs and areas of research that need to be addressed to enhance BCI-FES integration.
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Affiliation(s)
- Peter Boord
- University of Technology and Neopraxis Pty Ltd, Sydney, New South Wales, Australia
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Abstract
Neuroscience folklore has it that somatotopy in human primary somatosensory cortex (SI) has two significant discontinuities: the hands and face map onto adjacent regions in SI, as do the feet and genitalia. It has been proposed that these conjunctions in SI result from coincident sources of stimulation in the fetal position, where the hands frequently touch the face, and the feet the genitalia. Computer modeling using a Hebbian variant of the self-organizing Kohonen net is consistent with this proposal. However, recent work reveals that the genital representation in SI for cutaneous sensations (as opposed to tumescence) is continuous with that of the lower trunk and thigh. This result, in conjunction with reports of separate face innervation and its earlier onset of sensory function, compared to that of the rest of the body, allows a reappraisal of homuncular organization. It is proposed that the somatosensory homunculus comprises two distinct somatotopic regions: the face representation and that of the rest of the body. Principles of self-organization do not account satisfactorily for the overall homuncular map. These results may serve to alert computational modelers that intrinsic developmental factors can override simple rules of plasticity.
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Affiliation(s)
- Pasha Parpia
- Centre for Research in Cognitive Science, Schools of Informatics and Life Sciences, University of Sussex, Brighton, UK.
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Louppe JM, Nguyen JP, Robert R, Buffenoir K, de Chauvigny E, Riant T, Péréon Y, Labat JJ, Nizard J. Motor cortex stimulation in refractory pelvic and perineal pain: report of two successful cases. Neurourol Urodyn 2012; 32:53-7. [PMID: 22674567 DOI: 10.1002/nau.22269] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 04/19/2012] [Indexed: 11/06/2022]
Abstract
AIMS In some patients, with refractory chronic pelvic and perineal pain, pain and quality of life are barely alleviated despite optimal medical treatment, infiltrations and surgical release of the pudendal nerve. The management of these patients is complex, especially after failure of neuromodulation techniques (spinal cord stimulation. S3 nerve root stimulation and direct stimulation of the pudendal nerve). We report the first two cases illustrating the value of motor cortex stimulation (MCS), in this new indication. METHODS The history, decision-making process, intraoperative findings and results of this technique are presented. The perineal cortical area was identified by intraoperative motor evoked potentials in the external anal sphincter, confirming its location in the primary motor cortex between the inferior and superior limb positions. As predictive value of repetitive transcranial magnetic stimulation (rTMS) in the identification of responders to MCS for pain is now established, we performed pre-operative rTMS sessions for both patients. RESULTS The first patient was a 74-years-old woman who reported an 11-year history of left lateral perineal pain. The second patient was a 45-year-old woman who reported a 4-year history of perineal pain following hysterectomy with ovariectomy. After respectively 40 months and 19 months of follow up, both patients reported an improvement of pain ranging from 40 to 50%. Time to onset of pain on sitting was markedly improved from a few minutes to 90 minutes, and largely contributing to improvement of activities of daily living and of quality of life. CONCLUSION These two first cases suggest that motor cortex stimulation constitutes a new treatment for refractory pelvic and perineal pain, and should be considered after failure of conventional neuromodulation techniques, especially spinal cord stimulation.
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Affiliation(s)
- Jean-Marie Louppe
- Service de Neurochirurgie, Centre Hospitalier Universitaire, Nantes, France
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Georgiadis JR, Kringelbach ML. The human sexual response cycle: brain imaging evidence linking sex to other pleasures. Prog Neurobiol 2012; 98:49-81. [PMID: 22609047 DOI: 10.1016/j.pneurobio.2012.05.004] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 04/21/2012] [Accepted: 05/08/2012] [Indexed: 12/30/2022]
Abstract
Sexual behavior is critical to species survival, yet comparatively little is known about the neural mechanisms in the human brain. Here we systematically review the existing human brain imaging literature on sexual behavior and show that the functional neuroanatomy of sexual behavior is comparable to that involved in processing other rewarding stimuli. Sexual behavior clearly follows the established principles and phases for wanting, liking and satiety involved in the pleasure cycle of other rewards. The studies have uncovered the brain networks involved in sexual wanting or motivation/anticipation, as well as sexual liking or arousal/consummation, while there is very little data on sexual satiety or post-orgasmic refractory period. Human sexual behavior also interacts with other pleasures, most notably social interaction and high arousal states. We discuss the changes in the underlying brain networks supporting sexual behavior in the context of the pleasure cycle, the changes to this cycle over the individual's life-time and the interactions between them. Overall, it is clear from the data that the functional neuroanatomy of sex is very similar to that of other pleasures and that it is unlikely that there is anything special about the brain mechanisms and networks underlying sex.
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Affiliation(s)
- J R Georgiadis
- Department of Neuroscience/Section Anatomy, University Medical Center Groningen (UMCG), University of Groningen, Groningen, The Netherlands.
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Di Noto PM, Newman L, Wall S, Einstein G. The Hermunculus: What Is Known about the Representation of the Female Body in the Brain? Cereb Cortex 2012; 23:1005-13. [DOI: 10.1093/cercor/bhs005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Kikuchi T, Matsumoto R, Mikuni N, Yokoyama Y, Matsumoto A, Ikeda A, Fukuyama H, Miyamoto S, Hashimoto N. Asymmetric bilateral effect of the supplementary motor area proper in the human motor system. Clin Neurophysiol 2012; 123:324-34. [DOI: 10.1016/j.clinph.2011.06.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Revised: 05/28/2011] [Accepted: 06/11/2011] [Indexed: 12/01/2022]
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Lloyd DM, McKenzie KJ, Brown RJ, Poliakoff E. Neural correlates of an illusory touch experience investigated with fMRI. Neuropsychologia 2011; 49:3430-8. [PMID: 21889948 DOI: 10.1016/j.neuropsychologia.2011.08.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 08/02/2011] [Accepted: 08/18/2011] [Indexed: 11/18/2022]
Abstract
When asked to judge the presence or absence of near-threshold tactile stimuli, participants often report touch experiences when no tactile stimulation has been delivered ('false alarms'). The simultaneous presentation of a light flash during the stimulation period can increase the frequency of touch reports, both when touch is and is not present. Using fMRI, we investigated the BOLD response during both light-present and light-absent false alarms, testing predictions concerning two possible neural mechanisms underlying these illusory touch experiences: activation of a tactile representation in primary somatosensory cortex (SI) and/or activation of a tactile representation in late processing areas outside of sensory-specific cortex, such as medial prefrontal cortex (MPC). Our behavioural results showed that participants made false alarms in light-present and light-absent trials, both of which activated regions of the medial parietal and medial prefrontal cortex including precuneus, posterior cingulate and paracingulate cortex, suggesting the same underlying mechanism. However, only a non-significant increase in SI activity was measured in response to false alarm vs. correct rejection trials. We argue that our results provide evidence for the role of top-down regions in somatic misperception, consistent with findings from studies in humans and non-human primates.
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Affiliation(s)
- Donna M Lloyd
- School of Psychological Sciences, University of Manchester, Manchester, UK.
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Komisaruk BR, Wise N, Frangos E, Liu WC, Allen K, Brody S. Women's clitoris, vagina, and cervix mapped on the sensory cortex: fMRI evidence. J Sex Med 2011; 8:2822-30. [PMID: 21797981 DOI: 10.1111/j.1743-6109.2011.02388.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
INTRODUCTION The projection of vagina, uterine cervix, and nipple to the sensory cortex in humans has not been reported. AIMS The aim of this study was to map the sensory cortical fields of the clitoris, vagina, cervix, and nipple, toward an elucidation of the neural systems underlying sexual response. METHODS Using functional magnetic resonance imaging (fMRI), we mapped sensory cortical responses to clitoral, vaginal, cervical, and nipple self-stimulation. For points of reference on the homunculus, we also mapped responses to the thumb and great toe (hallux) stimulation. MAIN OUTCOME MEASURES The main outcome measures used for this study were the fMRI of brain regions activated by the various sensory stimuli. RESULTS Clitoral, vaginal, and cervical self-stimulation activated differentiable sensory cortical regions, all clustered in the medial cortex (medial paracentral lobule). Nipple self-stimulation activated the genital sensory cortex (as well as the thoracic) region of the homuncular map. CONCLUSION The genital sensory cortex, identified in the classical Penfield homunculus based on electrical stimulation of the brain only in men, was confirmed for the first time in the literature by the present study in women applying clitoral, vaginal, and cervical self-stimulation, and observing their regional brain responses using fMRI. Vaginal, clitoral, and cervical regions of activation were differentiable, consistent with innervation by different afferent nerves and different behavioral correlates. Activation of the genital sensory cortex by nipple self-stimulation was unexpected, but suggests a neurological basis for women's reports of its erotogenic quality.
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Affiliation(s)
- Barry R Komisaruk
- Department of Psychology, Rutgers University, Newark, NJ 07102, USA.
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