Slow-adapting type I (SA-I) afferents deliver sensory signals to the somatosensory cortex during low-frequency (or static) mechanical stimulation. It has been reported that the somatosensory projection from SA-I afferents is effective and reliable for object grasping and manipulation. Despite a large number of neuroimaging studies on cortical activation responding to tactile stimuli mediated by SA-I afferents, how sensory information of such tactile stimuli flows over the somatosensory cortex remains poorly understood. In this study, we investigated tactile information processing of pressure stimuli between the primary (SI) and secondary (SII) somatosensory cortices by measuring effective connectivity using dynamic causal modeling (DCM). We applied pressure stimuli for 3 s to the right index fingertip of healthy participants and acquired functional magnetic resonance imaging (fMRI) data using a 3T MRI system. DCM analysis revealed intra-hemispheric effective connectivity between the contralateral SI
In the somatosensory system, it is well known that the bilateral secondary somatosensory cortex (SII) receives projections from the unilateral primary somatosensory cortex (SI), and the SII cortex, in turn, sends feedback projections to SI. Most neuroimaging studies have clearly shown bilateral SII activation using only unilateral stimulation for both anatomical and functional connectivity across SII subregions. However, no study has unveiled differences in the functional connectivity of the contra- and ipsilateral SII network that relate to frontoparietal areas during tactile object recognition. Therefore, we used event-related functional magnetic resonance imaging (fMRI) and a delayed match-to-sample (DMS) task to investigate the contributions of bilateral SII during tactile object recognition. In the fMRI experiment, fourteen healthy subjects were presented with tactile angle stimuli on their right index finger and asked to encode three sample stimuli during the encoding phase and one test stimulus
Somatosensory Cortex: The primary somatosensory cortex is located in the postcentral gyrus, and is part of the somatosensory system.
A study has been made of the neuronal somata in the motor and somatic sensory cortices of the monkey. Pyramidal cells in the motor cortex are very similar to those described previously in sensory and parietal cortical areas. The largest pyramidal cells in area 4, the Betz cells of layer V, are up to 50 μm in transverse diameter. Although basically resembling smaller pyramidal cells, the nucleus of a Betz cell often has a complex indentation and is smaller in relation to the overall size of the cell soma than is that of a smaller pyramid and the cytoplasm of Betz cells contains discrete clumps of endoplasmic reticulum. As with other pyramidal cells, the synapses on to Betz cell somata are all of the symmetrical type. Previous descriptions of stellate cells have been of cells receiving a high density of axosomatic synapses of both the asymmetric and symmetrical type. Cells like this are found in both the motor and somatic sensory cortices and have been termed here large stellate cells. In ...
The effect of electrical somatosensory stimulation on motor performance of the affected hand was investigated in 12 chronic subcortical stroke subjects. Subjects performed index finger and hand tapping movements as well as reach-to-grasp movements with both the affected and unaffected hand prior to (baseline conditions) and following (i) two hours of electrical somatosensory stimulation (trains of 5 pulses at 10 Hz with 1 ms duration delivered at 1 Hz with an intensity on average 60% above the individual somatosensory threshold) of the median nerve of the affected hand or (ii) two hours of idle time on separate occasions at least one week apart. The order of sessions was counterbalanced across subjects. Somatosensory stimulation of the median nerve of the affected hand, but not a period of idle time, enhanced the frequency of index finger and hand tapping movements and improved the kinematics of reach-to-grasp movements performed with the affected hand, compared to baseline. Somatosensory ...
We used fMRI to establish whether attention to touch enhances somatosensory cortical activity. Subjects received somatosensory and visual stimulation and were instructed to attend selectively to one modality during alternating stimulus detection periods interspersed with rest periods during which no stimulus was delivered. The maximum signal change for each task versus rest was measured in anatomically defined regions of interest for each subject. Attended touch produced greater signal change than unattended touch in primary (S1) and secondary (S2) somatosensory cortex. In contrast to the conclusions of some previous studies, we found that the enhancement of activation with attention was at least as great in S1 as in S2. The attentional effect was unilateral in S1 and bilateral in S2 and the somatosensory insula.
In the mammalian neocortex, segregated processing streams are thought to be important for forming sensory representations of the environment, but how local information in primary sensory cortex is transmitted to other distant cortical areas during behaviour is unclear. Here we show task-dependent activation of distinct, largely non-overlapping long-range projection neurons in the whisker region of primary somatosensory cortex (S1) in awake, behaving mice. Using two-photon calcium imaging, we monitored neuronal activity in anatomically identified S1 neurons projecting to secondary somatosensory (S2) or primary motor (M1) cortex in mice using their whiskers to perform a texture-discrimination task or a task that required them to detect the presence of an object at a certain location. Whisking-related cells were found among S2-projecting (S2P) but not M1-projecting (M1P) neurons. A higher fraction of S2P than M1P neurons showed touch-related responses during texture discrimination, whereas a higher ...
It is established that reward can influence a wide range of overt human behaviors (Dehaene and Changeux, 2000; Glimcher and Rustichini, 2004; Pessiglione et al., 2006), with much recent interest in the neural basis of such reward influences (Platt and Glimcher, 1999; Schultz, 2000; Glimcher, 2001; Sugrue et al., 2004). Here, we extend the domain of reward-related influences to include early somatosensory processing, showing that reward can augment somatosensory performance (Fig. 1 b) and influence activity in human somatosensory cortex [Figs. 2 (right), 3 a-c, 4 a, 5 (right)]. Particularly striking is our observation that primary somatosensory cortex contralateral to the judged finger showed elevated hemodynamic response (or "reactivation" of stimulus-responsive regions) for reward delivery at trial end [Figs. 2 (right), 3], even though rewards for a correct somatosensory judgment were signaled only visually at this point. Moreover, this reactivation of primary somatosensory cortex increased ...
Secondary thalamic nuclei may provide stronger, longer-lasting input to superficial layers of primary sensory cortex than other cortical areas can.
The postcentral gyrus is a prominent gyrus in the lateral parietal lobe of the human brain. It is the location of the primary somatosensory cortex, the main sensory receptive area for the sense of touch. Like other sensory areas, there is a map of sensory space in this location, called the sensory homunculus. The primary somatosensory cortex was initially defined from surface stimulation studies of Wilder Penfield, and parallel surface potential studies of Bard, Woolsey, and Marshall. Although initially defined to be roughly the same as Brodmann areas 3, 1 and 2, more recent work by Kaas has suggested that for homogeny with other sensory fields only area 3 should be referred to as "primary somatosensory cortex", as it receives the bulk of the thalamocortical projections from the sensory input fields. ...
After nearly complete lesions of sensory afferents in the dorsal column (DC) of the spinal cord, the hand representation in contralateral primary somatosensory cortex (area 3b) of monkeys becomes deactivated and hand use is impaired. Nevertheless, neuronal responses to touch on the hand return over a few postlesion weeks, and hand use recovers (Jain et al., 1997, 1998, 2008; Qi et al., 2011, 2013; Chen et al., 2012). A critical finding of these studies is that the sparing of even a small proportion of the dorsal column afferents from the hand promotes the extent of the reactivation of cortex and the recovery of hand use. However, little is known about the response properties of reactivated cortical neurons. According to previous subjective measures after various sensory deprivations, reactivated cortical neurons often responded well to digit tactile stimulation (Merzenich et al., 1983a,b; Tommerdahl et al., 1996; Florence et al., 1998; Darian-Smith and Brown, 2000) and therefore seemed capable ...
Hoffer, Z.S, J.E. Hoover, and K.D. Alloway (2003) Sensorimotor corticocortical projections from rat barrel cortex have an anisotropic organization that facilitates integration of inputs from whiskers in the same row. Journal of Comparative Neurology, 466:525-544.. Alloway, K.D., Z.S. Hoffer, and J.E. Hoover (2003). Quantitative comparisons of the topographic organization in the ventrobasal complex and posterior nucleus of the rodent thalamus. Brain Research, 96:54-68.. Hoover, J.E., Z. Hoffer, K.D. Alloway (2003) Projections from primary somatosensory cortex to the neostriatum: the role of somatotopic continuity in corticostriatal convergence. Journal of Neurophysiology, 89:1576-1587.. 2000. Overlapping corticostriatal projections from the rodent vibrissal representations in primary and secondary somatosensory cortex. Journal of Comparative Neurology, 426:51-67. (with K. Alloway, J. Mutic, and Z. Hoffer).. 1999. The organization of cerebellar and basal ganglia outputs to primary motor cortex as ...
Purpose: Anterograde trans-synaptic degeneration along the visual pathway has been observed in glaucomatous patients and experimental glaucoma models. The aim of this study is to investigate the mechanisms and extent of trans-synaptic changes in the visual system as well as in the distant somatosensory cortex using a rodent model of optic nerve axotomy. It is known that the rat primary somatosensory centre has structural and functional inter-linkages with the visual cortex.. Methods: Optic nerve injury in the form of axotomy was performed in adult Sprague-Dawley rats. Animals were sacrificed at regular time points and tissues harvested. Immunoblotting followed by densitometric analysis was used to determine the phosphorylation profile of Akt in the dorsal lateral geniculate nucleus (dLGN), the visual cortex and the primary somatosensory cortex (S1). The neuronal cell size and cell density were measured using Nissl staining. The prevalence of apoptosis was characterized by terminal ...
The representation of pain in the cerebral cortex is less well understood than that of any other sensory system. However, with the use of magnetic resonance imaging and positron emission tomography in humans, it has now been demonstrated that painful heat causes significant activation of the contralateral anterior cingulate, secondary somatosensory, and primary somatosensory cortices. This contrasts with the predominant activation of primary somatosensory cortex caused by vibrotactile stimuli in similar experiments. Furthermore, the unilateral cingulate activation indicates that this forebrain area, thought to regulate emotions, contains an unexpectedly specific representation of pain. ...
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The somatosensory cortex controls the bodys sense of touch. This part of the brain is located behind the frontal lobe where the motor controls are located. The area is called the parietal lobe, and...
Neurofunctional Imaging of Plasticity in Mouse Somatic Sensory Cortex during Development and in Maturity: The color-coded images show energy metabolism in sections cut tangentially through the right cortical hemisphere. The quantitative autoradiographic deoxyglucose method was employed for neurofunctional imaging. Outlines of the barrels in somatic sensory cortex are superimposed on the images (The nose is to the right; the midline is up). When six whiskers, that is whiskers B1-3 and D1-3, on the left side were stimulated, focal regions of increased metabolic nerve cell activity (red) were found co-localized with the corresponding barrels B1-3 and D1-3 (top image; row A is outside the plane of section; the arrow points at barrel E1). The distinct gap of low activity between the highly activated regions comprises barrels C1-3. When the follicles of whiskers C1-3 were removed on the day of birth, the barrels that would have represented these whisker did not develop and the adjacent barrels ...
The main function of the primary somatosensory cortex (S1) is to process tactile information but it does receive sparse nociceptive innervation.18,19 While the arrangement and characteristics of S1 nociceptive neurones points to a role in the sensory discriminatory aspects of pain processing, several studies have also shown increases in S1 rCBF when attention is directed towards the stimulus.21 This may help to explain the psychophysical findings of increased accuracy of pain localisation during directed attention.. The secondary somatosensory cortex (S2) and insula are the most commonly activated regions described in the pain literature.15,22-26 Activation in these regions is bilateral and encompasses a region comprising the depth of the sylvian fissure and the parietal/frontal operculi. While difficult to discriminate when using group imaging, due to intraindividual variability, most studies depict two distinct loci within this region corresponding to the anterior insula and posterior ...
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The probability of synaptic transmitter release determines the spread of excitation and the possible range of computations at unitary connections. To investigate whether synaptic properties between neocortical pyramidal neurons change during the assembly period of cortical circuits, whole-cell volta …
El Archivo Digital UPM alberga en formato digital la documentacion academica y cientifica (tesis, pfc, articulos, etc..) generada en la Universidad Politecnica de Madrid.Los documentos del Archivo Digital UPM son recuperables desde buscadores: Google, Google Academics, Yahoo, Scirus, etc y desde recolectores OAI: E-ciencia, DRRD, Recolecta (REBIUN-FECYT), Driver, Oaister, etc.
Author: Spitzer, Bernhard et al.; Genre: Journal Article; Published in Print: 2014-05; Keywords: Working memory; Tactile; fMRI; Connectivity; Stimulus coding; Title: Maintenance and manipulation of somatosensory information in ventrolateral prefrontal cortex
Ratering, D; Baltes, C; Lohmann, C; Matter, C M; Rudin, M (2011). Accurate assessment of carotid artery stenosis in atherosclerotic mice using accelerated high-resolution 3D magnetic resonance angiography. Magma, 24(1):9-18.. Baltes, C; Bosshard, S; Mueggler, T; Ratering, D; Rudin, M (2011). Increased blood oxygen level-dependent (BOLD) sensitivity in the mouse somatosensory cortex during electrical forepaw stimulation using a cryogenic radiofrequency probe. NMR in Biomedicine, 24(4):439-446.. Ratering, D. Improving sensitivity per unit time in small animal MRI: Low temperature detection and parallel acquisition. 2010, ETHZ Diss.No 18954, Faculty of Medicine.. Yankam Njiwa, J; Ratering, D; Baltes, C; Rudin, M (2010). Increasing temporal resolution of DSC perfusion MRI using the analytic image concept. Magma, 23(4):251-261.. Ratering, D; Baltes, C; Nordmeyer-Massner, J A; Marek, D; Rudin, M (2008). Performance of a 200-MHz cryogenic RF probe designed for MRI and MRS of the murine brain. Magnetic ...
the expression of this firing phenotype. In particular, Kv3 channels are highly expressed by fast-spiking, arvalbuminpositive interneurons in corticolimbic brain circuits, which modulate the synchronization of cortical circuits and the generation of brain rhythms. Here, we describe a novel small molecule, (5R)-5-ethyl-3-(6-{[4-methyl-3-(methyloxy)phenyl]oxy}-3-pyridinyl)- 2,4-imidazolidinedione (AUT1), which modulates Kv3.1 and Kv3.2 channels in human recombinant and rodent native neurons. AUT1 increased whole currents mediated by human Kv3.1b and Kv3.2a channels, with a concomitant leftward shift in the voltage dependence of activation. A less potent effect was observed on hKv3.3 currents. In mouse somatosensory cortex slices in vitro, AUT1 rescued the fast-spiking phenotype of parvalbumin-positive-fast-spiking interneurons following an impairment of their firing capacity by blocking a proportion of Kv3 channels with a low concentration of tetraethylammonium. Notably, AUT1 had no effect on ...
Stroke are the main causes of motor disability among adults and are expected to impose an increasing social and economic burden for our Country. The impact of stroke on patients is enormous, with negative ramifications on the persons participation in social, vocational, and recreational activities. It is the primary cause of long-term disability in these countries. At the present stage, it is well known that control of balance during upright standing depends upon the central integration of afferent information from vestibular, somatosensory (proprioceptive, tactile), and visual systems, which constitute a multilink neural network for the control of neck, hip, and ankle joints. More recently, it has been studied at the level of cerebral cortex; vestibular inputs would reach face/neck representation of primary somatosensory cortex and would be then integrated with visual and somatosensory inputs in intraparietal, posterior end of the insula and medial superior temporal cortices. Remarkably, ...
Stroke are the main causes of motor disability among adults and are expected to impose an increasing social and economic burden for our Country. The impact of stroke on patients is enormous, with negative ramifications on the persons participation in social, vocational, and recreational activities. It is the primary cause of long-term disability in these countries. At the present stage, it is well known that control of balance during upright standing depends upon the central integration of afferent information from vestibular, somatosensory (proprioceptive, tactile), and visual systems, which constitute a multilink neural network for the control of neck, hip, and ankle joints. More recently, it has been studied at the level of cerebral cortex; vestibular inputs would reach face/neck representation of primary somatosensory cortex and would be then integrated with visual and somatosensory inputs in intraparietal, posterior end of the insula and medial superior temporal cortices. Remarkably, ...
The scientists used a computer program to average the PET data from the subjects within each group, and then compared the obese subjects average with the normal subjects result. The program produced three-dimensional images highlighting areas where the obese group had higher metabolic activity than the normal-weight group. The scientists then superimposed these images onto a magnetic resonance image (MRI) of the whole brain, as well as a diagram of the brain s somatosensory cortex, known as a homunculus. A homunculus graphically illustrates the relative number of sensory nerves innervating various parts of the body as well as where the input from these nerves is received on the somatosensory cortex. The overlapping images revealed hot spots indicating obese subjects higher metabolic activity in the regions of the parietal cortex where somatosensory input from the mouth, lips, and tongue is received. This is also an area involved with taste perception. The enhanced activation of these parietal ...
Anatomical vessel network extracted from two-photon scans of a rodent somatosensory cortex. In this work, the authors develop a hybrid model to solve for the time-varying oxygen advection-diffusion equation in the vessels and tissue. [See - Q. Fang, S. Sakadzic, L. Ruvinskaya, et. al., Fig. 4 for details.]. ...
Electrophysiology-delivery of fluorescent viral vectors-and two-photon microscopy were used to demonstrate the rapidity of axonal restructuring of both excitatory and inhibitory neurons in rodent cortical layer II/III following alterations in sensory experience.
Cortical compression can be a significant problem in many types of brain injuries, such as brain trauma, localized brain edema, hematoma, focal cerebral ischemia, or brain tumors. Mechanical and cellular alterations can result in global changes in excitation and inhibition on the neuronal network level even in the absence of histologically significant cell injury, often manifesting clinically as seizures. Despite the importance and prevalence of this problem, however, the preciseelectro physiological effects of brain injury have not been well characterized. In this study, the changes in electrophysiology were characterized following sustained cortical compression usinglarge-scale, multi electrode measurement of multiun it activity in primary somatosensory cortexinasensory-evoked, in vivoanimal model. Immediately following the initiation of injury at a distal site, there was a period of suppression of the evoked response in the rat somatosensory cortex, followed by hyper-excitability that was ...
Cortical compression can be a significant problem in many types of brain injuries, such as brain trauma, localized brain edema, hematoma, focal cerebral ischemia, or brain tumors. Mechanical and cellular alterations can result in global changes in excitation and inhibition on the neuronal network level even in the absence of histologically significant cell injury, often manifesting clinically as seizures. Despite the importance and prevalence of this problem, however, the preciseelectro physiological effects of brain injury have not been well characterized. In this study, the changes in electrophysiology were characterized following sustained cortical compression usinglarge-scale, multi electrode measurement of multiun it activity in primary somatosensory cortexinasensory-evoked, in vivoanimal model. Immediately following the initiation of injury at a distal site, there was a period of suppression of the evoked response in the rat somatosensory cortex, followed by hyper-excitability that was ...
Central sulcus - The groove (sulcus) on the brain that separates the primary somatosensory cortex (parietal lobe) from the primary motor cortex (frontal lobe).. ...
Principal Investigator:NISHIMURA Akira, Project Period (FY):2003 - 2005, Research Category:Grant-in-Aid for Scientific Research (C), Section:一般, Research Field:Pediatrics
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Motor rehabilitation therapy is commonly employed after strokes, but outcomes are variable and there is little specific information about the changes in brain activity that are associated with improved function. We performed serial functional MRI (fMRI) on a group of seven patients receiving a form of rehabilitation therapy after stroke in order to characterize functional changes in the brain that correlate with behavioural improvements. Patients were scanned while performing a hand flexion-extension movement twice before and twice after a two-week home-based therapy programme combining restraint of the unaffected limb with progressive exercises for the affected limb. As expected, the extent of improvement in hand function after therapy varied between patients. Therapy-related improvements in hand function correlated with increases in fMRI activity in the premotor cortex and secondary somatosensory cortex contralateral to the affected hand, and in superior posterior regions of the cerebellar hemispheres
Neurovascular coupling describes the mechanism by which the energy and oxygen demand arising from neuronal activity is met by an increase in regional blood flow, known as the haemodynamic response. Interleukin 1 (IL-1) is a pro-inflammatory cytokine and an important mediator of neuronal injury, though mechanisms through which IL-1 exerts its effects in the brain are not fully understood. In this study, we set out to investigate if increased cerebral levels of IL-1 have a negative effect on the neurovascular coupling in the cortex in response to sensory stimulation. We used two approaches to measure the neuronal activity and haemodynamic changes in the anaesthetised rat barrel somatosensory cortex in response to mechanical whisker stimulation, before and for 6 h after intra-striatal injection of interleukin-1β or vehicle. First, we used two-dimensional optical imaging spectroscopy (2D-OIS) to measure the size of the functional haemodynamic response, indicated by changes of oxyhaemoglobin (HbO2) and
Key to understanding somatosensation is the form of how the mechanical stimuli are represented in the evoked neuronal activity of the brain. Here, we focus on studies that address the question of which components of the evoked neuronal activity in the somatosensory system represent the stimulus features. We review experiments that probe whether these neuronal representations are essential to somatosensation. We also discuss recent results that suggest how the somatosensory stimuli are represented in the brain during short-term memory. Finally, we review data that show the neuronal correlates of a decision during somatosensory perception. (C) 2002 Elsevier Science B.V. All rights reserved. ...
Implants and robotics can now mimic senses. The feeling of touch is remarkable. It allows us to sense danger as well as communicate with other human beings on a more complex level, distinguishing us from many other creatures. Yet, most of us take this ability for granted as we have always had it since we were born.. For some individuals though, this is not always the case, such as Nathan Copeland, a 28-year-old American man, who lost this ability at the age of 18 when a car crash damaged his neck and spinal cord. For 10 years he could not feel anything and could only dream of a possibility of having his sense of touch restored. Through the use of micro-electrodes scientists were able to make a breakthrough and return the feeling of touch to him.. How was touch restored in a paralysed person?. Scientists first identified the parts of the brain associated with touch in the hands, namely the primary somatosensory cortex (touch sensing areas) located in the parietal lobe of the brain. Two electrodes ...
Transdermal neuromodulation of noradrenergic activity suppresses psychophysiological and biochemical stress responses in humans. Tyler, W.J., A. Boasso, H.M. Mortimore, R.S. Silva, J.D. Charlesworth, M.A. Marlin, K.A. Aebersold, L. Aven, D.Z. Wetmore, and S.K. Pal (2015). Scientific Reports 5, 13865, 1-17. PMID: 26353920. Is sham cTBS real cTBS? The effect on EEG dynamics. Opitz, A., W. Legon, J. Mueller, A. Barbour, W. Paulus, and W.J. Tyler (2015). Frontiers in Human Neuroscience 8, 1043. PMID: 25620925. Transcranial focused ultrasound modulates intrinsic and evoked EEG dynamics. Mueller, J., W. Legon, A. Opitz, T.F. Sato, W.J. Tyler (2014). Brain Stimulation 7(6), 900-908. PMID: 25265863. A quantitative overview of biophysical forces impinging on neural function. Mueller, J. and W.J. Tyler (2014). Physical Biology 11(5), 1-15. PMID: 25156965. Transcranial focused ultrasound modulates the activity of primary somatosensory cortex in humans. Legon, W., T.F. Sato, A. Opitz, J. Mueller, A. ...
Synonyms for artery of central sulcus in Free Thesaurus. Antonyms for artery of central sulcus. 11 synonyms for artery: vein, blood vessel, route, way, course, round, road, passage, avenue, arteria, arterial blood vessel. What are synonyms for artery of central sulcus?
In our recent paper (Miyashita et al., 2013), we showed that long-term, high-level channelrhodopsin-2 (ChR2) expression by in utero electroporation (IUE) produces structural abnormalities in the axons of ChR2-expressing pyramidal cells in rat somatosensory cortex. In the Discussion of our paper, we mentioned that such abnormalities were not observed in an earlier study using long-term IUE of ChR2 under the same promoter (Huber et al., 2008). A methodological difference has been brought to our attention that likely explains this difference. Huber et al. expressed wildtype ChR2 (Chop2-315 from Nagel et al., 2003), while we expressed hChR2 that was codon-optimized for higher mammalian expression (Zhang et al., 2006). This suggests that lower ChR2 protein levels in the Huber study may have enabled long-term expression without axonal malformations. This further supports our main conclusion that morphological abnormalities are associated with high-level, long-term expression of ChR2 protein, and that
Somatosensory (SI & SII) and Motor (MI) Cortices.Panels A and B - SI and MI in this study were defined as the central sulcus including its posterior wall, a
Normally each body part has its own area of representation in the cortex: that area will first receive the sensory information arriving from the respective body part. The size of the area depends upon the density of nerve fibres in that body part. For instance the thumb has a much larger representation area in the somatosensory cortex than the back. Earlier studies have shown that the size of these areas may continue to change in adulthood depending on the amount and frequency of sensory stimuli received in each area. For instance the representation area of an amputated arm will disappear altogether; its place will be taken over by the adjacent area, usually that of the fac,e, Nina Forss explains ...
This leads to irregularities they call "patches" in parts of the cortex which controls thoughts and actions.. Their latest research suggested these were responsible for the autistic-style problems seen in the mice such as repetitive behaviour and impaired sociability.. The patches are most common in a part of the brain known as S1DZ. Part of the somatosensory cortex, this region is believed to be responsible for sensing where the body is in space.. In these patches populations of cells called interneurons - which express a protein called parvalbumin - are reduced.. Interneurons are responsible for controlling the balance of excitation and inhibition in the brain. The changes found in the cortical patches caused over-excitement in S1DZ.. When the researchers restored normal levels of brain activity in this area they were able to reverse the behavioral abnormalities.. They were also able to induce the behaviors in otherwise normal mice by over-stimulating neurons in S1DZ.. The researchers also ...
Kristt, D A. and Waldman, J V., "Developmental reorganization of acetylcholinesterase-rich inputs to somatosensory cortex of the mouse." (1982). Subject Strain Bibliography 1982. 4234 ...
The Davidson Lab uses a diverse array of methods to investigate the encoding and plasticity of somatosensory information in the nervous system. ...
DI-fusion, le Dépôt institutionnel numérique de lULB, est loutil de référencementde la production scientifique de lULB.Linterface de recherche DI-fusion permet de consulter les publications des chercheurs de lULB et les thèses qui y ont été défendues.
Neocortical activity can evoke sensory percepts, but the cellular mechanisms remain poorly understood. We trained mice to detect single brief whisker stimuli and report perceived stimuli by licking to obtain a reward. Pharmacological inactivation and optogenetic stimulation demonstrated a causal role for the primary somatosensory barrel cortex. Whole-cell recordings from barrel cortex neurons revealed membrane potential correlates of sensory perception. Sensory responses depended strongly on prestimulus cortical state, but both slow-wave and desynchronized cortical states were compatible with task performance. Whisker deflection evoked an early (,50 ms) reliable sensory response that was encoded through cell-specific reversal potentials. A secondary late (50-400 ms) depolarization was enhanced on hit trials compared to misses. Optogenetic inactivation revealed a causal role for late excitation. Our data reveal dynamic processing in the sensory cortex during task performance, with an early ...
Vibrissectomy induced changes in GAP-43 immunoreactivity in the adult rat barrel cortex. Article date: 1992/1/8 PubMed ID: 1531989 Journal name: The Journal of comparative neurology (ISSN: 0021-9967) ABSTRACT Within the rat primary somatosensory cortex, neurons responding principally to movement of each individual mystacial vibrissa are grouped together in structures termed barrels. Previous studies have examined changes in the area of cortex showing increased 2-deoxyglucose uptake …