keyword
MENU ▼
Read by QxMD icon Read
search

Somatotopic

keyword
https://www.readbyqxmd.com/read/29335352/discrete-modules-and-mesoscale-functional-circuits-for-thermal-nociception-within-primate-s1-cortex
#1
Pai-Feng Yang, Ruiqi Wu, Tung-Lin Wu, Zhaoyue Shi, Li Min Chen
This study addresses one long-standing question of whether functional separations are preserved for somatosensory modalities of touch, heat and cold nociception within primate primary somatosensory (S1) cortex. This information is critical for understanding how the nature of pain is represented in the primate brain. Using a combination of submillimeter-resolution fMRI and microelectrode local field potential (LFP) and spike recordings, we identified spatially-segregated cortical zones for processing touch, nociceptive heat and cold stimuli in somatotopically appropriate areas 3a, 3b, 1, and 2 of S1 in male monkeys...
January 15, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29330326/loss-of-balance-between-striatal-feedforward-inhibition-and-corticostriatal-excitation-leads-to-tremor
#2
Yael Oran, Izhar Bar-Gad
Fast spiking interneurons (FSIs) exert powerful inhibitory control over the striatum and are hypothesized to balance the massive excitatory cortical and thalamic input to this structure. We recorded neuronal activity in the dorsolateral striatum and globus pallidus (GP) concurrently with the detailed movement kinematics of freely behaving female rats prior to and following selective inhibition of FSI activity using IEM-1460 microinjections. The inhibition led to the appearance of episodic rest tremor in the body part that depended on the somatotopic location of the injection within the striatum...
January 12, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29322527/thalamo-cortical-projections-to-the-macaque-superior-parietal-lobule-areas-pec-and-pe
#3
Daniele Impieri, Michela Gamberini, Lauretta Passarelli, Marcello G P Rosa, Claudio Galletti
The exposed surface of the superior parietal lobule in macaque brain contains two architectonically defined areas named PEc and PE. The aim of the present study is the characterization of thalamic afferents of these two areas. For this purpose, retrograde neuronal tracers were injected, or placed in crystal form, in areas PEc and PE. We found that the two areas show a similar pattern of thalamic inputs, mainly originating from Lateral Posterior (LP), Pulvinar (Pul), Ventral Posterior Lateral (VPL), and Ventral Lateral (VL) nuclei, all structures known to be involved in visual, somatosensory, and/or sensorimotor processing...
January 10, 2018: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/29311009/cortical-inhibitory-function-in-cervical-dystonia
#4
Christos Ganos, Elisa R Ferrè, Angela Marotta, Panagiotis Kassavetis, John Rothwell, Kailash P Bhatia, Patrick Haggard
OBJECTIVE: To assess the specificity of cortical inhibitory deficits in cervical dystonia patients. METHODS: A systematic test battery was developed to assess spatial and temporal aspects of cortical inhibition, in motor and somatosensory systems of the hand. We tested 17 cervical dystonia (CD) patients and 19 controls assessing somatosensory spatial inhibition (grating orientation test, interdigital feedforward subliminal inhibition), somatosensory temporal inhibition (temporal discrimination threshold, feedforward subliminal inhibition), motor spatial inhibition (surround inhibition), and motor temporal inhibition (short interval intracortical inhibition)...
December 1, 2017: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
https://www.readbyqxmd.com/read/29301873/visually-driven-maps-in-area-3b
#5
Esther Kuehn, Patrick Haggard, Arno Villringer, Burkhard Pleger, Martin I Sereno
Sensory perception relies on the precise neuronal encoding of modality-specific environmental features in primary sensory cortices. Some studies have reported the penetration of signals from other modalities even into early sensory areas. So far, no comprehensive account of maps induced by "foreign sources" exists. We addressed this question using surface-based topographic mapping techniques applied to ultra-high resolution fMRI neuroimaging data, measured in female participants. We show that fine-grained finger maps in human primary somatosensory cortex, area 3b, are somatotopically activated not only during tactile mechanical stimulation, but also when viewing the same fingers being touched...
January 4, 2018: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29285773/functional-architecture-of-the-somatosensory-homunculus-detected-by-electrostimulation
#6
Franck-Emmanuel Roux, Imène Djidjeli, Jean-Baptiste Durand
In this prospective electrostimulation study, based on 50 operated patients with no sensory deficit and no brain lesion in the postcentral gyrus, we acquired coordinates in the standard MNI space of the functional areas of the somatosensory homunculus. The 3D brain volume of each patient was normalized to that space to obtain the MNI coordinates of the stimulation site locations. For 647 sites stimulated on Brodmann Area 1 (and 1025 in gyri nearby), 258 positive points for somatosensory response (40%) were found in the postcentral gyrus...
December 29, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/29279733/efficacy-of-parietal-acupoint-therapy-scalp-acupuncture-for-neck-shoulder-stiffness-with-related-mood-disturbance
#7
Naoki Aoyama, Osamu Fujii, Toshikatsu Yamamoto
Objectives: Yamamoto New Scalp Acupuncture is a quick and effective microsystem of acupuncture used for treating various symptoms for which the somatotopic area is the scalp. This article describes Parietal Acupoint Therapy (PAPT), which is another approach, using a different scalp somatotopy, and to evaluate PAPT's effect on neck/shoulder stiffness and related mood disturbances. Materials and Methods:Subjects: Forty-six volunteers suffering from chronic neck/shoulder stiffness with various symptoms (headache, dizziness, and related mood disturbance) participated in this study and were randomly divided into 2 groups: treatment (26 subjects) and control (20 subjects)...
December 1, 2017: Medical Acupuncture
https://www.readbyqxmd.com/read/29248698/multiple-time-courses-of-somatosensory-responses-in-human-cortex
#8
P Avanzini, V Pelliccia, G Lo Russo, G A Orban, G Rizzolatti
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...
December 14, 2017: NeuroImage
https://www.readbyqxmd.com/read/29229431/altered-neurocognitive-processing-of-tactile-stimuli-in-patients-with-complex-regional-pain-syndrome-crps
#9
Anoop Kuttikat, Valdas Noreika, Srivas Chennu, Nicholas Shenker, Tristan Bekinschtein, Christopher A Brown
Chronic pain in CRPS has been linked to tactile misperceptions and deficits in somatotopic representation of the affected limb. Here, we identify altered cognitive processing of tactile stimuli in CRPS patients that we propose marks heterogeneity in tactile decision-making mechanisms. In a case-control design, we compared middle and late-latency somatosensory-evoked potentials (SEPs) in response to pseudo-randomised mechanical stimulation of the digits of both hands (including CRPS-affected and non-affected sides) between 13 CRPS patients and 13 matched healthy controls...
December 8, 2017: Journal of Pain: Official Journal of the American Pain Society
https://www.readbyqxmd.com/read/29215039/semantic-discrimination-impacts-tdcs-modulation-of-verb-processing
#10
Valentina Niccolai, Anne Klepp, Peter Indefrey, Alfons Schnitzler, Katja Biermann-Ruben
Motor cortex activation observed during body-related verb processing hints at simulation accompanying linguistic understanding. By exploiting the up- and down-regulation that anodal and cathodal transcranial direct current stimulation (tDCS) exert on motor cortical excitability, we aimed at further characterizing the functional contribution of the motor system to linguistic processing. In a double-blind sham-controlled within-subjects design, online stimulation was applied to the left hemispheric hand-related motor cortex of 20 healthy subjects...
December 7, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29194849/somatotopic-effects-of-rtms-in-neuropathic-pain-a-comparison-between-stimulation-over-hand-and-face-motor-areas
#11
N Andre-Obadia, M Magnin, E Simon, L Garcia-Larrea
BACKGROUND: The therapeutic influence of somatotopic matching between pain topography and motor cortex stimulation site for neuropathic pain (NP) remains controversial. METHODS: Thirty-two patients suffering from NP involving the upper limb (n = 20) or the face (n = 12) received two high-frequency rTMS neuronavigated sessions targeting hand and face motor cortical areas, versus placebo. The cortical target was defined by anatomical MRI and EMG responses in all patients, completed in 19 of them by functional MRI...
December 1, 2017: European Journal of Pain: EJP
https://www.readbyqxmd.com/read/29160240/remapping-cortical-modulation-for-electrocorticographic-brain-computer-interfaces-a-somatotopy-based-approach-in-individuals-with-upper-limb-paralysis
#12
Alan D Degenhart, Shivayogi V Hiremath, Ying Yang, Stephen T Foldes, Jennifer L Collinger, Michael L Boninger, Elizabeth C Tyler-Kabara, Wei Wang
OBJECTIVE: Brain-computer interface (BCI) technology aims to provide individuals with paralysis a means to restore function. Electrocorticography (ECoG) uses disc electrodes placed on either the surface of the dura or the cortex to record field potential activity. ECoG has been proposed as a viable neural recording modality for BCI systems, potentially providing stable, long-term recordings of cortical activity with high spatial and temporal resolution. Previously we have demonstrated that a subject with spinal cord injury (SCI) could control an ECoG-based BCI system with up to three degrees of freedom [Wang et al...
November 21, 2017: Journal of Neural Engineering
https://www.readbyqxmd.com/read/29159037/reorganization-of-the-somatosensory-cortex-in-hemiplegic-cerebral-palsy-associated-with-impaired-sensory-tracts
#13
Christos Papadelis, Erin E Butler, Madelyn Rubenstein, Limin Sun, Lilla Zollei, Donna Nimec, Brian Snyder, Patricia Ellen Grant
Functional neuroimaging studies argue that sensory deficits in hemiplegic cerebral palsy (HCP) are related to deviant somatosensory processing in the ipsilesional primary somatosensory cortex (S1). A separate body of structural neuroimaging literature argues that these deficits are due to structural damage of the ascending sensory tracts (AST). The relationship between the functional and structural integrity of the somatosensory system and the sensory performance is largely unknown in HCP. To address this relationship, we combined findings from magnetoencephalography (MEG) and probabilistic diffusion tractography (PDT) in 10 children with HCP and 13 typically developing (TD) children...
2018: NeuroImage: Clinical
https://www.readbyqxmd.com/read/29139557/using-somatosensory-mismatch-responses-as-a-window-into-somatotopic-processing-of-tactile-stimulation
#14
Guannan Shen, Nathan J Smyk, Andrew N Meltzoff, Peter J Marshall
Brain responses to tactile stimulation have often been studied through the examination of ERPs elicited to touch on the body surface. Here, we examined two factors potentially modulating the amplitude of the somatosensory mismatch negativity (sMMN) and P300 responses elicited by touch to pairs of body parts: (a) the distance between the representation of these body parts in somatosensory cortex, and (b) the physical distances between the stimulated points on the body surface. The sMMN and the P300 response were elicited by tactile stimulation in two oddball protocols...
November 15, 2017: Psychophysiology
https://www.readbyqxmd.com/read/29044874/information-processing-from-the-motor-cortices-to-the-subthalamic-nucleus-and-globus-pallidus-and-their-somatotopic-organizations-revealed-electrophysiologically-in-monkeys
#15
Hirokazu Iwamuro, Yoshihisa Tachibana, Yoshikazu Ugawa, Nobuhito Saito, Atsushi Nambu
To understand how the information derived from different motor cortical areas representing different body parts is organized in the basal ganglia, we examined the neuronal responses in the subthalamic nucleus (STN), and the external (GPe) and internal (GPi) segments of the globus pallidus, input, relay, and output nuclei, respectively, to stimulation of the orofacial, forelimb, and hindlimb regions of the primary motor cortex (MI) and supplementary motor area (SMA) in macaque monkeys under awake state. Most STN and GPe/GPi neurons responded exclusively to stimulation of either the MI or SMA, and one-fourth to one-third of neurons responded to both...
October 17, 2017: European Journal of Neuroscience
https://www.readbyqxmd.com/read/29022879/sparse-genetic-tracing-reveals-regionally-specific-functional-organization-of-mammalian-nociceptors
#16
William Olson, Ishmail Abdus-Saboor, Lian Cui, Justin Burdge, Tobias Raabe, Minghong Ma, Wenqin Luo
The human distal limbs have a high spatial acuity for noxious stimuli but a low density of pain-sensing neurites. To elucidate mechanisms underlying regional differences in processing nociception, we sparsely traced non-peptidergic nociceptors across the body using a newly generated Mrgprd(CreERT2) mouse line. We found that mouse plantar paw skin is also innervated by a low density of Mrgprd(+) nociceptors, while individual arbors in different locations are comparable in size. Surprisingly, the central arbors of plantar paw and trunk innervating nociceptors have distinct morphologies in the spinal cord...
October 12, 2017: ELife
https://www.readbyqxmd.com/read/28992938/bilateral-carpal-tunnel-syndrome-a-review
#17
REVIEW
Pawel Dec, Andrzej Zyluk
Carpal tunnel syndrome (CTS) is the most common upper extremity compressive neuropathy, with a prevalence of 3%-5% in the general population, and 6% in the group of females over the age of 40. It occurs about five times more common in females, with 2 peaks observed, in the 6th and 8th decades of life. Bilateral manifestation is more common than unilateral (60%), but significantly more often begins or is more strongly expressed in the dominant hand. Possible anatomical abnormalities underlying the development of CTS account for about 5% of cases...
October 2, 2017: Neurologia i Neurochirurgia Polska
https://www.readbyqxmd.com/read/28981612/local-global-parcellation-of-the-human-cerebral-cortex-from-intrinsic-functional-connectivity-mri
#18
Alexander Schaefer, Ru Kong, Evan M Gordon, Timothy O Laumann, Xi-Nian Zuo, Avram J Holmes, Simon B Eickhoff, B T Thomas Yeo
A central goal in systems neuroscience is the parcellation of the cerebral cortex into discrete neurobiological "atoms". Resting-state functional magnetic resonance imaging (rs-fMRI) offers the possibility of in vivo human cortical parcellation. Almost all previous parcellations relied on 1 of 2 approaches. The local gradient approach detects abrupt transitions in functional connectivity patterns. These transitions potentially reflect cortical areal boundaries defined by histology or visuotopic fMRI. By contrast, the global similarity approach clusters similar functional connectivity patterns regardless of spatial proximity, resulting in parcels with homogeneous (similar) rs-fMRI signals...
July 18, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28981418/covert-verb-reading-contributes-to-signal-classification-of-motor-imagery-in-bci
#19
Hong Zhang, Yaoru Sun, Jie Li, Fang Wang, Zijian Wang
Motor imagery is widely used in the brain-computer interface (BCI) systems that can help people actively control devices to directly communicate with the external world, but its training and performance effect is usually poor for normal people. To improve operators' BCI performances, here we proposed a novel paradigm, which combined the covert verb reading in the traditional motor imagery paradigm. In our proposed paradigm, participants were asked to covertly read the presented verbs during imagining right hand or foot movements referred by those verbs...
October 4, 2017: IEEE Transactions on Neural Systems and Rehabilitation Engineering
https://www.readbyqxmd.com/read/28968341/differential-effect-of-motor-cortex-stimulation-on-unit-activities-in-the-ventral-posterior-lateral-thalamus-in-cats
#20
Sandra Kobaïter-Maarrawi, Joseph Maarrawi, Nayef Saadé, Luis Garcia-Larrea, Michel Magnin
Although motor cortex stimulation (MCS) is being increasingly used to treat chronic refractory neuropathic pain in humans, its mechanisms of action remain elusive. Studies in animals have suggested the involvement of subcortical structures, in particular the thalamus. Most of these studies have been carried out in rats, a species presenting significant differences in thalamic anatomy and function relative to primates, in particular a very limited number of thalamic GABA interneurons. The aim of this study was to investigate the effects of MCS on single-unit activities of the thalamic ventral posterior lateral (VPL) nucleus in cats, which contains substantial numbers of GABA interneurons...
September 29, 2017: Pain
keyword
keyword
63114
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"