Primary Somatosensory Cortex


RESULTS: Following ES during distraction, there was a significant linear trend (P < .05) in which the intensity of cerebral activation in the primary somatosensory cortex (SI) (bilateral) and left mid-anterior cingulate cortex (ACC) increased with stimulation intensity.  

However, recent studies demonstrate reduced activation of primary somatosensory cortex (S1) with continuous vibrotactile tracking during bimodal stimulation. The purpose of the current paper was to use TMS to assess the effects of differential sensorimotor requirements in the right sensorimotor cortex upon local intracortical networks and sensory processing in the left primary somatosensory cortex during constant multimodal stimulation.  

By way of psychophysiological interaction analysis, we also investigated the functional connectivity of the primary somatosensory cortex (S1) in patients and controls.  

Multislice gradient echo images of the primary somatosensory cortex were obtained using a 7.05 T superconducting system and a one-turned surface coil centered over the primary somatosensory cortex of the 1.0%-isoflurane-anesthetized rat.  

OBJECT: The aim of this study was to investigate the usefulness of a short train of high-frequency (500 Hz) cortical stimulation to delineate the primary motor cortex (MI), supplementary motor area (SMA), primary somatosensory cortex (SI), supplementary sensory area (SSA), negative motor area (NMA), and supplementary negative motor area (SNMA) in patients with epilepsy who were undergoing functional mapping.  

Activity within premotor and ipsilateral primary somatosensory cortex decreased over scans for externally cued finger flexion and over sessions for self-paced finger flexion.  

The primary somatosensory cortex (S1 area) is one of the key brain structures for central processing of somatic noxious information to produce pain perception.  

Within-group analysis showed that both patients and controls activated the primary motor cortex, the primary somatosensory cortex, the somatosensory association cortex, and the middle cerebellar peduncles.  

Infragranular layers constitute the main output of the primary somatosensory cortex and represent an important stage of cortico-cortical and cortico-subcortical integration. We have previously used chronic multiple single-unit recordings to study the spatiotemporal structure of tactile responses of infragranular neurons within the forepaw cortical representation in rats [ Tutunculer B, Foffani G, Himes BT, Moxon KA (2006) Structure of the excitatory receptive fields of infragranular forelimb neurons in the rat primary somatosensory cortex responding to touch. These results show that the spatiotemporal structure of tactile responses of infragranular neurons extends across all four paws, and provide the basic architecture for studying physiological integration and pathophysiological reorganization of tactile information in the infragranular layers of the rat primary somatosensory cortex..  

All recordings were localized to the contralateral primary somatosensory cortex as revealed by BOLD at 11.7 T.  

RESULTS: The main centers affected in the NERD-H patients included the secondary somatosensory cortex (SII), primary somatosensory cortex (S1), right prefrontal cortex (PFC), right orbitofrontal cortex (OFC), insular cortex, amygdala, striatum, motor cortex and its supplementary area, and cerebellum cortices, which form part of the matrix controlling emotional, autonomic modulatory responses to pain.  

RESULTS: This study used a tone-laser conditioning paradigm to establish the pain expectation in rats, and simultaneously recorded the anterior cingulate cortex (ACC), the medial dorsal thalamus (MD), and the primary somatosensory cortex (SI) to investigate the effect of pain expectation on laser-induced neuronal responses.  

We recently discovered the neuronal representation of proprioceptive eye position signal in monkey primary somatosensory cortex..  

Several recent studies have provided support for the view that tactile stimuli/events are remapped into an abstract spatial frame of reference beyond the initial somatotopic representation present in the primary somatosensory cortex.  

Remarkably, primary somatosensory cortex contralateral to the judged hand was reactivated at the point of reward delivery, despite the absence of concurrent somatosensory input at that time point. This side-specific reactivation of primary somatosensory cortex increased monotonically with level of reward. Moreover, the level of reward received on a particular trial influenced somatosensory performance and neural activity on the subsequent trial, with better discrimination and enhanced hemodynamic response in contralateral primary somatosensory cortex for trials that followed higher rewards.  

Postural vertical was more tilted in right than in left hemisphere strokes and specifically biased by damage to neural circuits centred around the primary somatosensory cortex and thalamus.  

The formalin stimulation at the hind paw of rats resulted in significant metabolic increases in the bilateral cingulate cortex, motor cortex, primary somatosensory cortex, secondary somatosensory cortex, insular cortex, visual cortex, caudate putamen, hippocampus, periaqueductal gray, amygdala, thalamus, and hypothalamus. Among the measured areas, clear lateralization was only evident in the primary somatosensory cortex and hypothalamus.  

The latency of evoked unit activities was 209.75 +/- 26.62 ms and the threshold of the ACC responses was 10 times greater than that in primary somatosensory cortex (SI).  

The current study presents results indicating that neurons across most of the extent of the hand representation in monkey primary somatosensory cortex (area 3b) interact, even when these neurons have separate RFs. We obtained simultaneous recordings by using a 100-electrode array implanted in the hand representation of primary somatosensory cortex of two anesthetized owl monkeys. Because spike synchrony potentiates the activation of commonly targeted neurons, synchronous neural activity in primary somatosensory cortex can contribute to discrimination of complex tactile stimuli..  

Previous studies have shown that rat vibrissae resonate, conferring frequency specificity to trigeminal ganglion (NV) and primary somatosensory cortex (SI) neurons during suprathreshold sensory stimulation.  

This "visual enhancement of touch" (VET), might involve modulation of primary somatosensory cortex (SI) processing by multimodal information related to the body.  

Given that the primary somatosensory cortex maps skin location independently of arm posture [ 1, 2], the brain must realign tactile coordinates in order to locate the origin of the stimuli in extrapersonal space. We propose that this early somatotopic "glimpse" arises from the initial feed-forward sweep of neural activity to the primary somatosensory cortex, whereas the later externally-based, conscious experience reflects the activity of a somatosensory network involving recurrent connections from association areas..  

Here we examine the spatial and temporal distribution of biotinylated VV in tangential sections through layer IV of the posteromedial barrel subfield in the primary somatosensory cortex (PMBSF) of rats ranging from postnatal day (P)3 to P60, which underwent unilateral deafferentation of whiskers at birth.  

We have investigated the alterations that the long-term implant of sieve electrodes to the peripheral nerves could evoke in the central nervous system by studying the neural activity at various levels of the somatosensory system [ the implanted nerves, the dorsal column nuclei (DCN), and the primary somatosensory cortex (SI)] up to 30 months after implantation of the electrode in the distal median nerve in adult cats.  

primary somatosensory cortex (SI) and posterior parietal cortex (PPC) are activated by noxious stimulation.  

Fine-scale functional organization of the finger areas in the human primary somatosensory cortex was investigated by high-resolution BOLD MRI at 3 T using a multi-echo FLASH sequence with a voxel size of 2 mm(3). When registered onto the individual high-resolution MRI anatomy and compared with cytoarchitectonical maps, the finger representations were confirmed to lie within Brodmann area 3b as the main input region of the primary somatosensory cortex..  

Functional magnetic resonance imaging mapping of the finger somatotopy in the primary somatosensory cortex requires a reproducible and precise stimulation.  

The classic understanding of the role of the primary somatosensory cortex (SI) is to be a first major unimodal area processing somatosensory input and reflecting the physical location of peripheral stimulation in the form of the famous homunculus.  

The effect was specific for the hippocampal formation, with levels of alpha1d mRNA unaltered by ADX in the lateral amygdala, reticular thalamic nucleus, retrosplenial cortex or primary somatosensory cortex.  

We used neuromagnetic source imaging to map the topography in primary somatosensory cortex (SI) while manipulating the visibility of a touched hand.  

In all three conditions, initial responses in left primary somatosensory cortex (SI) were observed ~20 to 50 ms after stimulus onset and were followed by additional left SI responses and bilateral responses in the secondary somatosensory cortex (SII).  

The effects of photothrombotic stroke in primary somatosensory cortex on astroglial and microglial activation in various regions of lesioned brain were examined at different time points, using immunohistochemistry and lectin binding.  

Neural activity coherent with the stimulus occurred in the contralateral primary somatosensory cortex in all subjects, and matched well with equivalent dipole modeling of the same data.  

WS-H patients showed a modest medial shift in primary somatosensory cortex activation relative to the WS-L group.  

As expected, positive BOLD signal changes were observed in the contralateral primary and bilateral secondary somatosensory areas, whereas a decreased BOLD signal was observed in the ipsilateral primary somatosensory cortex (SI).  

We examined the region- and time-dependent transcriptional profiles of six IEGs (c-fos, fosB, fra-1, junB, c-jun and egr-1) by in situ hybridization after acute corticosterone challenge in the hippocampus and the primary somatosensory cortex (S1).  

OBJECTIVE: To clarify the characteristics relating to the temporal dynamics of the tongue primary somatosensory cortex (SI).  

Damage and/or disconnection of the primary somatosensory cortex (SI) after stroke leads to deficits in touch perception.  

METHODS: Somatosensory-evoked potentials were recorded from the primary somatosensory cortex and the vertex location (SI/Vx-SEPs). primary somatosensory cortex and vertex location recorded SEPs and AI/Vx-AEPs were recorded alternately, during CRI of dexmedetomidine (4.0, 10.0, 20.0 microg kg(-1) hour(-1)) and a control (saline). RESULTS: The primary somatosensory cortex-evoked potentials were not affected by the dexmedetomidine CRI, but the other three parameters were significantly affected; although the AI-SEP to a lesser extent than the Vx-SEP and Vx-AEP.  

No accompanying learning-related changes were observed in the primary somatosensory cortex, which mediates the unconditioned stimulus.  

Bilateral air-pulse stimulation was associated with the activation of a bilateral network including the primary somatosensory cortex and the thalamus, classic motor areas (primary motor cortex, supplementary motor area, cingulate motor areas), and polymodal areas (including the insula and frontal cortex).  

Previous studies indicate that transcranial magnetic stimulation (TMS) with biphasic pulses applied approximately over the primary somatosensory cortex (S1) suppresses performance in vibrotactile temporal discrimination tasks; these previous results, however, do not allow separating perceptual influence from memory or decision-making.  

The hierarchical relationship of the rat primary somatosensory cortex (S1) and secondary somatosensory cortex (S2) is controversial.  

A guidance screw was implanted in the skull of the rats, over the forelimb representation area of the primary somatosensory cortex (S1fl), allowing repetitive injections at the same stereotactic coordinates.  

To clarify the computational role of large receptive fields for cortical processing of somatosensory information, we recorded ensembles of single neurons from the infragranular forelimb/forepaw region of the rat primary somatosensory cortex while tactile stimuli were separately delivered to different locations on the forelimbs/forepaws under light anesthesia.  

The aim of this study was to explore the influence of tactile spatial-selective attention on spatiotemporal aspects of evoked neuronal activity in the primary somatosensory cortex (S1).  

To elucidate the dental pulp-representing area in the human primary somatosensory cortex and the presence of A-beta fibers in dental pulp, we recorded somatosensory-evoked magnetic fields from the cortex in seven healthy persons using magnetoencephalography. The current source generating the early component of the magnetic fields was located anterior-inferiorly compared with the locations for the hand area in the primary somatosensory cortex. These results demonstrate the dental pulp representation area in the primary somatosensory cortex, and that it receives input from intradental A-beta neurons, providing a detailed organizational map of the orofacial area, by adding dental pulp to the classic "sensory homunculus"..  

However, most functional MRI studies did not detect signal change in the primary somatosensory cortex during pain empathy. To test if the perception of pain in others involves the primary somatosensory cortex, neuromagnetic oscillatory activity was recorded from the primary somatosensory cortex in 16 participants while they observed static pictures depicting body parts in painful and non-painful situations. Compared to the baseline condition, the level of the approximately 10-Hz oscillations was suppressed during both of the observational situations, indicating the activation of the primary somatosensory cortex. These results, consistent with the mirror-neuron system, demonstrate that the perception of pain in others modulates neural activity in primary somatosensory cortex and supports the idea that the perception of pain in others elicits subtle somatosensory activity that may be difficult to detect by fMRI techniques..  

A significant difference between the sight of an intentional touch, compared to an accidental touch, was found in the left primary somatosensory cortex (SI/Brodmann's area [ BA] 2).  

In both block and event-related design, the analysis revealed an activation pattern comprising the contralateral primary motor cortex, primary somatosensory cortex and premotor cortex; the ipsilateral cerebellum; bilateral secondary somatosensory cortex, the supplementary motor area and anterior cingulate cortex.  

CONCLUSIONS: The decrease in alpha over the contralateral temporal scalp during cold pain is consistent with pain-related activity in the primary somatosensory cortex and/or the somatosensory association areas located in the parietal operculum and/or insula.  

We studied the modulation of the topographic arrangement of the human ipsilateral primary somatosensory cortex following interference of nociceptive stimuli by means of dipole source analysis.  

In the human somatosensory system, the contralateral primary somatosensory cortex (SI) is presumed to process and encode type and intensity of the sensory inputs, whereas the bilateral secondary somatosensory cortex (SII) is believed to perform higher order functions including sensorimotor integration, integration of information from the two body halves, attention, learning and memory.  

Timing-dependent plasticity in human primary somatosensory cortex.  

We have begun preliminary studies of the effectiveness of electrical stimulation in the proprioceptive area of the primary somatosensory cortex (area 3a) as a potential means to deliver an artificial sense of proprioception to a monkey.  

Activation maps derived from smoothed echo planar imaging (EPI) data by volume- and surface-based analyses were assigned to the nodes of individual cortical surface models, and local maxima in the primary motor area (M1) and the primary somatosensory cortex (S1) were compared with those derived from non-smoothed risk map analysis, which is commonly used in presurgical applications.  

Vibration-related neurons in monkey primary somatosensory cortex (SI) discharge rhythmically when vibratory stimuli are presented.  

Six levels of electrical stimulation were delivered to a rat's hind paw and responses of several neighboring neurons were simultaneously recorded in the primary somatosensory cortex.  

Though somatotypic representation within the face in human primary somatosensory cortex (S1) to innocuous stimuli is controversial; previous work suggests that painful heat is represented based on an "onion-skin" or segmental pattern on the face.  

We show that cerebral activations in contralateral primary somatosensory cortex (SI) are markedly correlated with different behavioural characteristics of these animals.  

Furthermore, the activation was structured with a line of symmetry through the central sulcus reflecting inputs both to primary somatosensory cortex and, precentrally, to primary motor cortex.  

In a subsequent fMRI experiment, performed with a similar task, two cortical areas in the left and right hemispheres were significantly correlated with the behavioural facing effect: primary somatosensory cortex (BA 2) and inferior frontal gyrus (BA 44).  

SERT, but not 5-HT(1B) immunoreactivity, was decreased in the primary somatosensory cortex during barrel specification.  

However, it is still unknown if anodal tDCS (tDCS(anodal)) applied to the primary somatosensory cortex (S1) can lead to behavioral changes in performance of tactile discriminative tasks.  

Using single unit recordings we investigate the effect of chronic morphine exposure on the firing properties of neurons in layers IV and V of the whisker-related area of rat primary somatosensory cortex.  

In the present study, we investigate the representation of orientation at the somatosensory periphery and in primary somatosensory cortex.  

Both systems use glutamate as neurotransmitter, as do the thalamocortical axons relaying somatosensory information from the VP to the primary somatosensory cortex (SI).  

OBJECTIVE: Multiple cortical areas including the primary somatosensory cortex are known to be involved in nociception.  

In order to further elucidate the underlying natural variation in mouse primary somatosensory cortex, we measured the size of the posterior medial barrel subfield (PMBSF), associated with the representation of the large mystacial vibrissae, in an expanded sample set that included 42 BXD RI strains, two parental strains (C57BL/6J and DBA/2J), and one F1 strain (B6D2F1).  

We imaged three cortical regions in rat: primary visual cortex (V1), barrel field of primary somatosensory cortex (S1bf) and parietal association area (PA, flanked by V1 and S1bf).  

Other areas evoking movements included primary somatosensory cortex (area 3b), two lateral somatosensory areas (areas PV and S2), and a caudal somatosensory area.  

These results suggest that the sacral M30 and M50 are responses from the primary somatosensory cortex.  

This article sought to: (1) assess effects of intermodal temporal synchrony upon modulation of primary somatosensory cortex (S1) during continuous sensorimotor transformations, (2) identify cortical areas sensitive to temporal synchrony, and (3) provide further insight into the reduction of S1 activity during continuous vibrotactile tracking previously observed by our group (Meehan and Staines [ 2007]: Brain Res 1138:148-158).  

To address these issues we introduced the light-gated algal channel channelrhodopsin-2 (ChR2) specifically into a small fraction of layer 2/3 neurons of the mouse primary somatosensory cortex.  

By combining low-frequency repetitive and single-pulse transcranial magnetic stimulation, we found that virtual lesions of ventral premotor cortex (vPMc) and primary somatosensory cortex (S1) suppressed mirror motor facilitation contingent upon observation of possible and impossible movements, respectively.  

Halothane and alpha-chloralose established baseline states of high and low energy, respectively, in which forepaw stimulation excited the contralateral primary somatosensory cortex (S1).  

The analysis showed that the activity of primary somatosensory cortex neurons covaried with the stimulus strength but did not covary with the animal's perceptual reports.  

Significantly less suppression of P27 with a lack of significant change in N20 indicates that the impairment of somatosensory information processing in the time domain is due to dysfunction within the primary somatosensory cortex, suggesting that that the STD deficit in FHD is more attributable to dysfunction in the somatosensory pathway..  

To gain new insights into the underpinning mechanisms of CP symptoms we investigated the long-term effects of PA and disuse on the hind limb musculoskeletal histology and topographical organization in the primary somatosensory cortex (S1) of adult rats.  

The aim of this study was to investigate the effect of neuronavigated TBS over primary somatosensory cortex (SI) on laser-evoked potentials (LEPs) and acute pain perception induced with Tm : YAG laser stimulation.  

Postsurgical pain was associated with increased activity in the contralateral primary somatosensory cortex.  

To understand how information is coded in the primary somatosensory cortex (S1) we need to decipher the relationship between neural activity and tactile stimuli.  

The forelimb-stump region of primary somatosensory cortex (S-I) of these rats contains neurons in layer IV that express both stump and hindlimb receptive fields.  

Simultaneous stimulation of two adjacent fingers above sensory perception threshold (supraliminal stimulation) leads to an inhibitory interaction effect on responses in primary somatosensory cortex (SI).  

Microgyria in primary somatosensory cortex (S1) of rats are associated with a reduced behavioral detection of rapid auditory transitions and the loss of large cells in the thalamic nucleus projecting to primary auditory cortex (A1).  

CONCLUSIONS: The primary somatosensory cortex may be a relevant structure in paroxysmal exercise-induced dystonia.  

Using a seed-voxel analysis strategy, region-specific, anesthetic dose-dependent fMRI resting-state functional connectivity was detected in bilateral primary somatosensory cortex (S1FL) of the resting brain.  

In the early post-operative period, the patient who had had the hand transplantation revealed strong activation of a higher motor area, only weak activation of the primary sensorimotor motor cortex and no activation of the primary somatosensory cortex. Activation of the primary somatosensory cortex was only seen at the 2-year follow-up.  

The primary somatosensory cortex reorganises more and the activation pattern is more bilateral compared to a healthy hand.  

Increased fMRI activation for both evoked and spontaneous tics was observed throughout cortical and subcortical structures commonly observed in experimental pain studies with healthy subjects; including the primary somatosensory cortex, insula, anterior cingulate, and thalamus.  

Decreased activation was seen in the bilateral primary motor cortices and the ipsilateral primary somatosensory cortex corresponding to the shoulder, elbow and hand.  

RESULTS: In 8 of the 12 subjects, activation over the contralateral primary somatosensory cortex was detected, correlating significantly with the predicted hemodynamic response function.  

There were clear coherence peaks at approximately 17.5 Hz for cells in the primary somatosensory cortex (both proprioceptive and cutaneous areas) and posterior parietal cortex (area 5).  

The primary somatosensory cortex has an exquisite somatotopic map where each individual whisker is represented in a discrete anatomical unit, the "barrel," allowing precise delineation of functional organization, development, and plasticity.  

Critically, after 1 Hz repetitive TMS interference [ 6] over the PPC, but not over the primary somatosensory cortex, phosphene detection was still enhanced by spatially coincident touches with uncrossed hands, but it was enhanced by spatially noncoincident touches after hand crossing.  

Moreover, the microinjection of paroxetine into the basolateral amygdala or cingulate cortex reduced anxiety-related behavior, and microinjection into the primary somatosensory cortex significantly attenuated thermal hyperalgesia.  

To investigate whether this type of adaptation might also be found in other sensory modalities, we characterized the intensity-response functions of neurons in rat primary somatosensory cortex (S1) to continuous sinusoidal vibration of the whiskers with amplitudes that were changed every 40 ms.  

Repetitive deflection of many right-sided whiskers at 10 Hz evoked a positive BOLD response that extended across contralateral primary somatosensory cortex (SI) and secondary somatosensory cortex (SII).  

Using in vivo patch-clamp technique, the slow oscillation of membrane currents was characterized by its synaptic nature, correlation with electroencephalogram (EEG) and responses to different anesthetic agents, in primary somatosensory cortex (SI) neurons in urethane-anesthetized rats.  

Within-case comparisons revealed that the percentage of PMv connections with contralateral SMA and PMd are higher than the percentage of PMv connections with these areas in the ipsilateral hemisphere; percentages of PMv connections with contralateral M1 rostral, FR, AO, and the primary somatosensory cortex are lower than percentages of PMv connections with these areas in the ipsilateral hemisphere.  

A main effect of modality with more activation during heat hyperalgesia was found in primary somatosensory cortex (S1), ACC, PFC, and PA.  

Twelve to 16 h after stereotaxic injections of MnCl(2) to the ventroposterior thalamic nuclei, an overall increase in signal intensity was detected in primary somatosensory cortex compared to other brain regions.  

In the auditory pacing condition it was localized in contralateral primary somatosensory cortex, during tactile pacing it was localized in contralateral posterior parietal cortex.  

In na├»ve rats, no significant difference was observed in total expression level of the two JNK isoforms between spinal cord and primary somatosensory cortex (S1 area).  

Cortical representation in response to spared forelimb stimulation was observed to enlarge and invade adjacent sensory-deprived hind limb territory in the primary somatosensory cortex as early as 3 days after injury.  

Robust activations in contralateral primary somatosensory cortex (SI) and thalamus were observed and peaked at the stimulus frequency of 9 Hz.  

Here we investigate neuronal responses in the rat primary somatosensory cortex (S1) and ventral posterior medial nucleus of the thalamus (VPM) during a tactile discrimination task that requires animals to associate two different tactile stimuli with two corresponding choices of spatial trajectory to be rewarded.  

We assumed the cortical organization for face movements from changes in MRN (mastication-related neuron) activities recorded at area M (motor cortex) and orofacial behaviors after the lesion in the facial SI (facial region in the primary somatosensory cortex).  

We have employed anterograde axonal tracing and 3D computerized reconstruction techniques to characterize the branching pattern and morphology of individual cerebropontine axons from the primary somatosensory cortex (SI).  

A number of human and animal studies have reported a differential representation of the frequency of vibrotactile stimuli in the somatosensory cortices: neurons in the primary somatosensory cortex (SI) are predominantly responsive to lower frequencies of tactile vibration, and those in the secondary somatosensory cortex (SII) are predominantly responsive to higher frequencies.  

By applying independent component analysis (ICA) to the ERP data, we found independent components (ICs) located in the medial prefrontal cortex (around the anterior cingulate cortex, ACC) and the primary somatosensory cortex (SI).  

Those disorders are altered impulse conductivity at all levels including peripheral neuron to nerve trunk, from the trunk to primary somatosensory cortex.  

Such lesions render the corresponding part of the somatotopic representation of primary somatosensory cortex totally unresponsive to tactile stimuli.  

Functional neuroimaging has demonstrated that a relationship exists between the intensity of deafferentation pain and the degree of deafferentation-related reorganization of the primary somatosensory cortex. If TMS is capable of suppressing deafferentation pain, this benefit should be also obtained by the implantation of epidural stimulating electrodes over the area of electrophysiological signal abnormality in the primary somatosensory cortex.  

In the present study, we tested whether a few minutes of intermittent theta burst stimulation (iTBS) over left primary somatosensory cortex (SI) evokes excitability changes within the stimulated brain area and whether such changes are accompanied by changes in tactile discrimination behavior.  

These changes were accompanied by an expansion of the cortical finger representation in primary somatosensory cortex (SI).  

In the present study, quantitative blot immunolabeling technique was used to determine the spatial and temporal expression of ERK1 and ERK2, as well as their activated forms, in the spinal cord, primary somatosensory cortex (SI area of cortex), and hippocampus under normal, transient pain and persistent pain states.  

Knowledge of time, modulated by the cerebellum, basal ganglia and primary somatosensory cortex, would also input to the pacing algorithm as would information stored in memory about previous similar exercise bouts.  

Recently, we have demonstrated that the fine-digit topography (millimeter sized) previously identified in the primary somatosensory cortex (SI), using electrophysiology and intrinsic signal optical imaging, can also be mapped with submillimeter resolution using blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging at high field.  

We compared the localizations of left and right thumb and little finger in the primary somatosensory cortex obtained with fMRI and MEG.  

The left primary somatosensory cortex increased in activity with increasing pain report, during attention to visceral pain. These results suggest that pain intensity perception during attentional modulation is reflected in the primary somatosensory cortex (visceral pain) and aIns cortex activity (somatic pain)..  

The topographic arrangement of the human primary somatosensory cortex following deafferentation of the contralateral cortex has been investigated by means of dipole source analysis.  

In primary sensory areas, like primary visual cortex and primary somatosensory cortex, the peak intensity of IOSs occurred in layer IV, which receives the main thalamic input.  

Optical changes at four simultaneously recorded wavelengths were measured in both rat and mouse primary somatosensory cortex (S1) evoked by forepaw stimulation to create four spectral maps. On average, hemodynamics were as expected in rat primary somatosensory cortex (S1): the fractional change in the log of HbT concentration increased monophasically 2 s after stimulus, whereas HbO changes mirrored HbR changes, with HbO showing a small initial dip at 0.5 s followed by a large increase 3.0 s post stimulus.  

The comparison of the RLS patients versus controls yielded significant regional decreases of gray matter volume at corrected P < 0.05 in the bihemispheric primary somatosensory cortex, which additionally extended into left-sided primary motor areas.  

Here, using in vivo two-photon Ca2+ imaging, we demonstrate that approximately 5% of sulforhodamine 101-labeled astrocytes in the hindlimb area of the mouse primary somatosensory cortex exhibit short-latency (peak amplitude approximately 0.5 s after stimulus onset), contralateral hindlimb-selective sensory-evoked Ca2+ signals that operate on a time scale similar to neuronal activity and correlate with the onset of the hemodynamic response as measured by intrinsic signal imaging.  

Tactile sensory information is first channeled from the primary somatosensory cortex on the postcentral gyrus to the parietal opercular region (i.e., the secondary somatosensory cortex) and the rostral inferior parietal lobule and, from there, to the prefrontal cortex, with which bidirectional connections exist.  

Sensory stimulation of the forepaw or the hindpaw in rats that experienced only partial denervation resulted in activation in only the appropriate, contralateral, primary somatosensory cortex (SI).  

BACKGROUND: Cortical whisker barrels in the primary somatosensory cortex are a well-known example of brain function in rodents.  

Short interfering RNAs (siRNA) targeting TNFalpha were incubated with cortical cell cultures and microinjected into the primary somatosensory cortex (SSctx) of rats.  

Here, we report a series of experiments in which owl monkeys performed reaching movements guided by spatiotemporal patterns of cortical microstimulation delivered to primary somatosensory cortex through chronically implanted multielectrode arrays.  

The equivalent current dipole (ECD) was located in the contralateral primary somatosensory cortex (cSI) for the first component, and in the cSI and in the contralateral secondary somatosensory cortex (cSII) for the fourth component.  

Recent studies suggest that in contrast to traditional views of the body map the topographic representation in primary somatosensory cortex (SI) reflects the perceived rather than the physical aspects of peripheral stimulation.  

1102(1), 109-116 (Aug 2)] proposed that tactile spatial discriminative performance is improved following adaptation because adaptation is accompanied by an increase in the spatial contrast in the response of contralateral primary somatosensory cortex (SI) to mechanical skin stimulation--an effect identified in previous imaging studies of SI cortex in anesthetized non-human primates [ e.g., Simons, S.B., Tannan, V., Chiu, J., Favorov, O.V., Whitsel, B.L., Tommerdahl, M, 2005.  

We demonstrate that the human caudate nucleus is interconnected with the prefrontal cortex, inferior and middle temporal gyrus, frontal eye fields, cerebellum and thalamus; the putamen is interconnected with the prefrontal cortex, primary motor area, primary somatosensory cortex, supplementary motor area, premotor area, cerebellum and thalamus.  

Overt minus imagined singing revealed increased activation in cortical (bilateral primary motor; M1) and subcortical (right cerebellar hemisphere, medulla) motor as well as in sensory areas (primary somatosensory cortex, bilateral A1).  

We examined whether stimulation of the basal forebrain affects regional cerebral blood flow in the primary somatosensory cortex in cats. In anesthetized cats with spinal cord transection at the T1 level, focal electrical stimulation of the unilateral basal forebrain increased the blood flow of the ipsilateral primary somatosensory cortex that was increased by stimulation of the contralateral forepaw, without any change in blood pressure. The response was the largest when the tip of the electrode was located within the area known to contain the basal forebrain neurons projecting to the primary somatosensory cortex. These results suggest that basal forebrain neurons projecting to the primary somatosensory cortex have a vasodilative function in cats, as previously found in rats..  

Stimulus-evoked activity for memory and control trials was generally indistinguishable within the network of regions normally responsive to experimental pain [ i.e., the primary somatosensory cortex/posterior parietal cortex (SI/PPC), secondary somatosensory cortex (SII), and anterior insular cortex (aIC)]; these data confirm the painful nature of the stimuli and the similar levels of attention and stimulus encoding engaged during the two randomly presented trial types.  

Here, by using magnetoencephalography, we show that selective nociceptive stimuli induce gamma oscillations between 60 and 95 Hz in primary somatosensory cortex. These results show that pain induces gamma oscillations in primary somatosensory cortex that are particularly related to the subjective perception of pain.  

RESULTS: The short-latency components of the source located in the right primary somatosensory cortex (SI: 43, 54 and 65ms) after tibial nerve stimulation, the mid-latency SI component (87ms) after sural nerve stimulation, and the mid-latency components in the right (approximately 161ms) and left (approximately 168ms) secondary somatosensory cortices (SII) were smaller in the presence of SCS than in absence of SCS.  

We use somatosensory stimulation and a suite of in vivo imaging tools to study neurovascular coupling in rat primary somatosensory cortex.  

Random effects analysis revealed significant attention effects in area SI (primary somatosensory cortex) in that the blood oxygenation level-dependent response was greater for attended than for ignored stimuli.  

Compared to young subjects, older subjects had significantly smaller pain-related fMRI responses in anterior insula (aINS) (P < 0.04), primary somatosensory cortex (S1) (P = 0.03), and supplementary motor area (P = 0.02).  

Thus, the current study was designed (1) to replicate previous work showing a lack of schizophrenia deficit in primary somatosensory cortex (SI) gating, and (2) to investigate a possible deficit in secondary somatosensory cortex (SII) gating.  

Here we investigated the effect of chronic deprivation of ipsilateral sensory whiskers on receptive field plasticity in primary somatosensory cortex.  

Here we demonstrate a representation of eye position in monkey primary somatosensory cortex, in the representation of the trigeminal nerve, near cells with a tactile representation of the contralateral brow.  

Painful stimulation resulted in highly reproducible activation over three scanning sessions in the anterior insula, primary somatosensory cortex, and anterior cingulate cortex. A significant decrease in strength of activation occurred from session 1 to session 3 in the anterior cingulate cortex, primary somatosensory cortex, and supplementary motor cortex, which may be explained by an analogous decrease in pain ratings.  

Measurements of miniature EPSPs suggested that synaptic inputs to layer 2/3 pyramidal neurons were altered at the junction of deprived and spared cortex in primary somatosensory cortex.  

In contrast, evaluation of sensory features of noxious information has long been thought to be accomplished by the primary somatosensory cortex and other structures associated with the lateral pain system.  

Tactile deprivation in rats produced by whisker-trimming early in life leads to abnormally robust responses of excitatory neurons in layer 4 of primary somatosensory cortex when the re-grown whiskers are stimulated.  

Both in C-AVE and in L-AVE, clear activations were found in the contralateral primary somatosensory cortex (SI) and bilateral parasylvian regions, whose activities peaked 163-181 ms after the stimulation.  

Sensory information originating in individual whisker follicles ascends through focused projections to the brainstem, then to the ventral posteromedial nucleus (VPM) of the thalamus, and finally into barrels of the primary somatosensory cortex (S1).  

Behavioral tactile discrimination thresholds were compared with functional magnetic resonance imaging measurements of cortical finger representations within primary somatosensory cortex (S1) for 10 human subjects to determine whether cortical magnification in S1 could account for the variation in tactile hyperacuity thresholds of the fingers.  

We investigated movements without proprioceptive feedback using ischemic nerve block during fMRI in healthy humans, and found preserved activation of the primary somatosensory cortex.  

Complete bilateral destruction of the cochleae and bilateral lesions of the auditory cortex (AuC) eliminated the effects of TM stimulation on RSNA and BP, but bilateral lesions of primary somatosensory cortex (S1C) had no effect.  

An early response, M50c, generated in the contralateral primary somatosensory cortex (SI), was not modulated by attention.  

BACKGROUND: Our goal was to examine the spatiotemporal integration of tactile information in the hand representation of human primary somatosensory cortex (anterior parietal somatosensory areas 3b and 1), secondary somatosensory cortex (S2), and the parietal ventral area (PV), using high-resolution whole-head magnetoencephalography (MEG).  

In the primary somatosensory cortex, expression was localized in the barrel field, including the zone of representation of vibrissae, fore and hind limbs, jaws, and head. In the cortex, expression of transgene 6A-99 began on day 3 of postnatal development (P3) and embraced only the area of primary somatosensory cortex: zones of representation of the snout, vibrissae, and lower jaw.  

We report three patients with reflex toothbrushing-induced epilepsy associated with small circumscribed structural lesions in the primary somatosensory cortex in close proximity to the hand and speech motor areas.  

Paired stimulation evoked response/long loop reflex and jerk-locked evoked responses evaluate the excitability changes of the primary somatosensory cortex.  

The effects of differential aversive Pavlovian conditioning on the functional organization of primary somatosensory cortex (SI) were examined in 17 healthy participants.  

The functional magnetic resonance imaging and magnetoencephalography results provided evidence of cortical reorganization [ changes in somatotopic maps in the primary somatosensory cortex (S1)].  

To determine the 'hard palate representing' area in the primary somatosensory cortex, we recorded somatosensory-evoked magnetic fields from the cortex in ten healthy volunteers, using magnetoencephalography. These results demonstrated the precise location of palatal representation in the primary somatosensory cortex, the actual area being small..  

Lesion locations in the primary, premotor, and supplementary motor cortices, primary somatosensory cortex, and anterior part of the posterior limb of the internal capsule were determinants for the AI of the intermediate zone (R(2)=0.785).  

The reciprocal connections between primary motor cortex (M1) and primary somatosensory cortex (S1) are hypothesized to play a role in an animal's ability to update its motor plan in response to changes in the sensory periphery.  

Innocuous electrical stimulation of the rat forepaw delineated BOLD contrast responses consistent with known somatosensory processing pathways (contralateral primary somatosensory cortex (S1), a region consistent with secondary somatosensory cortex, the ventral posterolateral thalamic nucleus and ipsilateral cuneate nucleus), providing face validity for the technique.  

We present a novel method to relate magnetoencephalography (MEG) and BOLD fMRI data from primary somatosensory cortex within the context of the linear convolution model.  

LFPs and 918 single units were recorded from primary motor cortex (M1), primary somatosensory cortex (S1, areas 3a and 2), posterior parietal cortex (area 5) and the deep cerebellar nuclei (DCN).  

Here, we studied spike timing-dependent synaptic depression in single putative pyramidal neurons of the rat primary somatosensory cortex (S1) in vivo, using two techniques.  

Here we applied optical imaging of intrinsic signal to observing the temporal-spatial characteristic of rat primary somatosensory cortex during graded electrical stimulation of the sciatic nerve (5 Hz, duration of 2 s, 0.5 ms pulse, 1 and 10 muscle twitching threshold). Meanwhile, we found the inverted optical signal changes in the regions surround the activated primary somatosensory cortex.  

The present paper sought 1) to determine the effects of intermodal selective attention on primary somatosensory cortex (S1) during continuous sensorimotor transformations, 2) to investigate the interactions of spatial relationship between the target and distracter modalities on S1 and 3) to identify any potential modulators during continuous sensorimotor transformations.  

Our results suggest that adaptation enhances tactile representations in primary somatosensory cortex, where they could directly influence perceptual decisions..  

To investigate neural coding characteristics in the human primary somatosensory cortex, two fingers with different levels of functional skill were studied.  

It was shown that the SEP recorded from vertex (Vx-SEP) did correlate with the unpleasantness, whereas the SEP recorded from the primary somatosensory cortex (SI-SEP) did not.  

ICA separated a prominent IC in the primary somatosensory cortex whereas the GLM-based analysis failed to show any touch-related activation.  

Connections of representations of the teeth and tongue in primary somatosensory cortex (area 3b) and adjoining cortex were revealed in owl, squirrel, and marmoset monkeys with injections of fluorescent tracers.  

Viewing video clips showing pain and tactile stimuli delivered to others, respectively, increased and decreased the amplitude of the P45 SEP component that reflects the activity of the primary somatosensory cortex (S1).  

The contribution of platelet-activating factor (PAF) to the induction of neocortical LTP was examined in rat brain slices containing the primary somatosensory cortex (SI).  

Sustained spatial attention was found to be mediated in primary somatosensory cortex with no differences in SSSEP amplitude topographies between attended and unattended body locations.  

We show that a similar unilateral microinjection of IL1beta (10 ng) into layer VI or onto the surface of the primary somatosensory cortex induced increases in the neuronal activity marker, Fos, relative to the contralateral side that received saline or heat-inactivated IL1beta. Further, the number of NGF-immunoreactive cells in the primary somatosensory cortex and magnocellular preoptic nucleus increased on the IL1beta-injected side.  

This paradigm exploits the fact that tactile input to neurons at early levels (e.g., the primary somatosensory cortex, SI) is largely confined to the contralateral side of the body, so these neurons are less able to contribute to vibration comparisons between hands.  

Sexual stimulation of the clitoris (compared to rest) significantly increased rCBF in the left secondary and right dorsal primary somatosensory cortex, providing the first account of neocortical processing of sexual clitoral information.  

In contrast to the fractured cerebellar map, the primary somatosensory cortex (SI) is somatotopically organized.  

To achieve this, single-unit activities of the face primary somatosensory cortex (face-SI) neurons responding to low-intensity electrical stimulation of the inferior alveolar nerve (IAN) and the jaw-opening reflex (JOR) were recorded during mastication in awake rabbits.  

Many Fos protein-like immunoreactive (Fos protein-LI) cells were expressed in the trigeminal spinal nucleus caudalis (Vc), parabrachial nucleus, parafascicular nucleus, a wide area of the primary somatosensory cortex, anterior cingulate cortex, amygdala, periaqueductal gray, solitary tract nucleus, and lateral hypothalamus following heating of the face during PRO or PEN infusion.  

The present report compares the morphology of callosal axon arbors projecting from and to the hind- or forelimb representations in the primary somatosensory cortex (SI) of the agouti (Dasyprocta primnolopha), a large, lisencephlic Brazilian rodent that uses forelimb coordination for feeding.  

We assessed the physiological significance of L1 inputs by performing extracellular recordings in vivo from neurons in the primary somatosensory cortex of rodents.  

The primary somatosensory cortex (SI) exhibits a detailed topographic organization of the hand and fingers, which has been found to undergo plastic changes following modifications of the sensory input.  

DISCUSSION: Our findings suggest that an extensive, predominantly fronto-limbic network of brain regions, including the insular cortex, mediates perception of noxious gastric fundic distension in healthy humans, without significant participation by the primary somatosensory cortex.  


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