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Simultaneous early processing of sensory input in human primary (SI) and secondary (SII) somatosensory cortices

JOURNAL OF NEUROPHYSIOLOGY 1999年第5期81卷 2017-2025页

作者： Karhu, J Tesche, CD Aalto Univ Brain Res Unit Low Temp Lab FIN-02015 Espoo Finland Kuopio Univ Hosp Dept Clin Neurophysiol Kuopio 70211 Finland

The anatomic connectivity of the somatosensory system supports the simultaneous participation of widely separated cortical areas in the early processing of sensory input. We recorded evoked neuromagnetic responses noninvasively from human primary (SI) and secondary (SII) somatosensory cortices to unilateral median nerve stimulation. Brief current pulses were applied repetitively to the median nerve at the wrist at 2 Hz for 800-1,500 trials. A single pulse was omitted from the train at random intervals (15% of omissions). We observed synchronized neuronal population activity in contralateral SII area 20-30 ms after stimulation, coincident in time with the first responses generated in SI. Both contra- and ipsilateral SII areas showed prominent activity at 50-60 ms with an average delay of 13 ms for ipsilateral compared with contralateral responses. The refractory behavior of the early SII responses to the omissions differed from those observed at similar to 100 ms, indicative of distinct neuronal assemblies responding at each latency. These results indicate that SII and/or associated cortices in parietal operculum, often viewed as higher-order processing areas for somatosensory perception, are coactivated with SI during the early processing of intermittent somatosensory input.

关键词：电刺激磁共振成像脑磁图描记术正中神经/生理学神经元/生理学感觉/生理学躯体感觉皮质/解剖学和组织学躯体感觉皮质/细胞学躯体感觉皮质/生理学时间因素成年人人类中年人

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SPATIAL-ORGANIZATION OF PRECENTRAL CORTEX IN AWAKE PRIMATES .3. INPUT-OUTPUT COUPLING

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JOURNAL OF NEUROPHYSIOLOGY 1978年第5期41卷 1132-1139页

作者： MURPHY, JT KWAN, HC MACKAY, WA WONG, YC UNIV TORONTO DEPT PHYSIOL TORONTO M5S 1A8 ONTARIO CANADA

Experiments involving sensory inputs to loci in the forelimb region of precentral cortex and motor outputs from these same loci were performed in awake monkeys [Macaca arctoides]. The sensory inputs involved extracellular unit responses of single neurons to cutaneous stimulation or to passive rotations of limb parts about joints. Motor outputs were determined in terms of movement of limb parts about joints in response to low-current (< 30 .mu.A) intracortical microstimulation (ICMS) with the same electrode used for recording. With only extremely rare exceptions, a homonymous relationship existed between input and output. A negative correlation existed between direction of ICMS effect and direction of effective passive joint rotation. ICMS of cortical sites induced movement either toward or away from the cutaneous receptive field of that site, with about equal frequency. Vertical aggregates of cells with similar input-output properties existed in a direction parallel to the radial fibers and orthogonal to the cortical surface. The conjugation of all clusters functionally related to single joints produces ring or crescent-shaped zones. Specific sensory inputs can apparently assist the central facilitation of neuronal clusters in precentral cortex, thereby playing a role in the sequencing of movement vectors during execution of behavioral action.

关键词：脑图电刺激前肢/神经支配额叶/生理学直鼻猴亚目关节/神经支配猕猴属运动皮质/解剖学和组织学运动皮质/生理学运动(Movement) 肌/神经支配神经通路/生理学神经元/生理学皮肤/神经支配躯体感觉皮质/解剖学和组织学躯体感觉皮质/生理学觉醒状态/生理学动物

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Neuromagnetic correlates of sensorimotor synchronization

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JOURNAL OF COGNITIVE NEUROSCIENCE 2000年第4期12卷 546-555页

作者： Müller, K Schmitz, F Schnitzler, A Freund, HJ Aschersleben, G Prinz, W Univ Dusseldorf Neurol Klin MEG Lab D-40225 Dusseldorf Germany

Sensorimotor synchronization tasks, in which subjects have to tap their finger in synchrony with an isochronous auditory click, typically reveal a synchronization error with the tap preceding the click by about 20 to 50 msec. Although extensive behavioral studies and a number of different explanatory accounts have located the cause of this so-called "negative asynchrony" on different levels of processing, the underlying mechanisms are stilt nor completely understood. Almost nothing is known about the central processes, in particular, which sensory or motor events are synchronized by subjects. The present study examined central-level processing in synchronization tasks with magnetoencephalography (MEG). Eight subjects synchronized taps with their right index finger to an isochronous binaural pacing signal presented at an interstimulus interval of 800 msec. To gain information on central temporal coupling between "tap" and "click," evoked responses were averaged time-lacked to the auditory signal and the tap onset. Tap-related responses could he explained with a three dipole model: One source, peaking at approximately 77 msec before tap onset, was localized in contralateral primary motor cortex (MI);the two other sources, peaking approximately at tap onset and 75 msec after tap onset, in contralateral primary somatosensory cortex (ST). Temporal coupling of these sources was compared in relation to different trigger points. The second SI source was equally well time-locked to the tap and to the auditory click. Furthermore, analysis of the time locking of this source activity as a function of the temporal order of tap and click showed that the second event-irrespective whether tap or click-was decisive in triggering the second SI source. This suggests that subjects use mainly sensory feedback in judging and evaluating whether they are "keeping time."

关键词：声刺激听觉皮质/生理学行为/生理学脑图皮质同步化磁共振成像脑磁图描记术反应时间/生理学躯体感觉皮质/解剖学和组织学躯体感觉皮质/生理学成年人女(雌)性人类男(雄)性

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SPATIAL-ORGANIZATION OF PRECENTRAL CORTEX IN AWAKE PRIMATES .1. SOMATOSENSORY INPUTS

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JOURNAL OF NEUROPHYSIOLOGY 1978年第5期41卷 1107-1119页

作者： WONG, YC KWAN, HC MACKAY, WA MURPHY, JT UNIV TORONTO DEPT PHYSIOL TORONTO M5S 1A8 ONTARIO CANADA

A large population of single units was recorded extracellularly in the precentral forelimb area of awake monkeys (Macaca arctoides]. Single units received information about either cutaneous stimulation (C-neurons), or limb part rotations about joints (J-neurons), or both. Receptive fields (RF) of C-neurons varied in size according to their location at the periphery. Distal limb C-neurons generally had smaller RF than proximal limb C-neurons. Most J-neurons responded to rotation of only a single joint;a small number responded to rotation of 2, but always contiguous, joints. Both C- and J-neurons receiving bilateral inputs were found only in cytoarchitectonic area 6. Cortical neurons with identical peripheral receptive fields, but subserving different sensory modalities, were found in vertically arranged aggregates. When the data was presented on an unfolded precentral cortex, multiple horizontal clusters, each of which consisted of several adjacent vertical aggregates, were revealed. These clusters were irregularly shaped and interleaved with other clusters. Segregation of horizontal clusters in terms of various forelimb joints revealed a nested organization with the proximal joint enclosing a central core of distal joint zones.

关键词：传入通路/生理学脑图前肢/神经支配额叶/解剖学和组织学额叶/生理学直鼻猴亚目猕猴属机械感受器/生理学神经纤维/生理学神经元/生理学躯体感觉皮质/解剖学和组织学躯体感觉皮质/生理学觉醒状态/生理学动物

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The somatosensory evoked magnetic fields

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PROGRESS IN NEUROBIOLOGY 2000年第5期61卷 495-523页

作者： Kakigi, R Hoshiyama, M Shimojo, M Naka, D Yamasaki, H Watanabe, S Xiang, J Maeda, K Lam, K Itomi, K Nakamura, A Natl Inst Physiol Sci Dept Integrat Physiol Okazaki Aichi 4448585 Japan Natl Inst Longev Sci Dept Biofunct Res Aichi Japan

Averaged magnetoencephalography (MEG) following somatosensory stimulation, somatosensory evoked magnetic field(s) (SEF), in humans are reviewed. The equivalent current dipole(s) (ECD) of the primary and the following middle-latency components of SEF following electrical stimulation within 80-100 ms are estimated in area 3b of the primary somatosensory cortex (SI), the posterior bank of the central sulcus, in the hemisphere contralateral to the stimulated site. Their sites are generally compatible with the homunculus which was reported by Penfield using direct cortical stimulation during surgery. SEF to passive finger movement is generated in area 3a or 2 of SI, unlike with electrical stimulation. Long-latency components with peaks of approximately 80-120 ms are recorded in the bilateral hemispheres and their ECD are estimated in the secondary somatosensory cortex (SII) in the bilateral hemispheres. We also summarized (1) the gating effects on SEF by interference tactile stimulation or movement applied to the stimulus site, (2) clinical applications of SEF in the fields of neurosurgery and neurology and (3) cortical plasticity (reorganization) of the SI. SEF specific to painful stimulation is also recorded following painful stimulation by CO2 laser beam. Pain-specific components are recorded over 150 ms after the stimulus and their ECD are estimated in the bilateral SII and the limbic system. We introduced a newly-developed multi (12)-channel gradiometer system with the smallest and highest quality superconducting quantum interference device (micro-SQUID) available to non-invasively detect the magnetic fields of a human peripheral nerve. Clear nerve action fields (NAFs) were consistently recorded from all subjects. (C) 2000 Elsevier Science Ltd. All rights reserved.

关键词：脑图诱发电位躯体感觉/生理学脑磁图描记术躯体感觉皮质/解剖学和组织学躯体感觉皮质/生理学人类

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CONNECTIONS OF AREAS 3B AND 1 OF THE PARIETAL SOMATOSENSORY STRIP WITH THE VENTROPOSTERIOR NUCLEUS IN THE OWL MONKEY (AOTUS-TRIVIRGATUS)

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JOURNAL OF COMPARATIVE NEUROLOGY 1979年第2期185卷 355-371页

作者： LIN, CS MERZENICH, MM SUR, M KAAS, JH VANDERBILT UNIV DEPT PSYCHOL NASHVILLE TN 37240 USA VANDERBILT UNIV DEPT ANAT NASHVILLE TN 37240 USA VANDERBILT UNIV DEPT ELECT ENGN NASHVILLE TN 37240 USA UNIV CALIF SAN FRANCISCO COLEMAN MEM LAB SAN FRANCISCO CA 94143 USA

Anatomical tracers were injected into electrophysiologically defined sites in somatosensory cortical Area 3b (SI proper) and Area I (posterior cutaneous field) of owl monkeys after these cortical subdivisions had been extensively explored in microelectrode mapping experiments. These mapping experiments revealed that both Areas 3b and 1 contain complete and separate representations of the body surface (Merzenich et al., ''78). Restricted injections of the retrograde tracer, horseradish peroxidase (HRP), into either Area 3b or Area 1 labeled neurons within a band of cells in the ventroposterior nucleus (VP). The location of the labeled band in VP varied with the location of the injection site in both representations, and the labeled region of VP was overlapping for injections in corresponding body parts in the 2 representations. Neurons projecting to the hand and foot cortical representations were in architectonically identified subnuclei. Because injections into either Area 3b or Area 1 labeled over half of the neurons in the appropriate regions of VP, it appears that some neurons in VP project to both cortical representations. Injections of HRP combined with the anterograde tracer, 3H-proline, indicate that VP neurons are reciprocally interconnected with both Areas 3b and 1.

关键词：美洲枭猴/解剖学和组织学脑图类人猿亚目神经通路/解剖学和组织学皮肤/神经支配躯体感觉皮质/解剖学和组织学丘脑核/解剖学和组织学动物

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Tickling expectations: Neural processing in anticipation of a sensory stimulus

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JOURNAL OF COGNITIVE NEUROSCIENCE 2000年第4期12卷 691-703页

作者： Carlsson, K Petrovic, P Skare, S Petersson, KM Ingvar, M Karolinska Hosp Karolinska Inst Dept Clin Neurosci Clin Neurophysiol Sect S-17176 Stockholm Sweden

Predictions of the near future can optimize the accuracy and speed of sensory processing as well as of behavioral responses. Previous experience and contextual cues are essential elements in the generation of a subjective prediction. Using a blocked fMRI paradigm, we investigated the pattern of neural activation in anticipation of a sensory stimulus and during the processing of the somatosensory stimulus itself. Tickling was chosen as the somatosensory stimulus rather than simple touch in order to increase the probability to get a high degree of anticipation. The location and nature of the stimulus were well defined to the subject. The state of anticipation was initiated by attributing an uncertainty regarding the time of stimulus onset. The network of activation and deactivation during anticipation of the expected stimulus was similar to that engaged during the actual sensory stimulation. The areas that were activated during both states included the contralateral primary sensory cortex, bilateral areas in the inferior parietal lobules, the putative area SII, the right anterior cingulate cortex and areas in the right prefrontal cortex. Similarly, common decreases were observed in areas of sensorimotor cortex located outside the area representing the target of stimulus, i.e., areas that process information which is irrelevant to the attended process. The overlapping pattern of change, during the somatosensory stimulation and the anticipation, furthers the idea that predictions are subserved by a neuronal network similar to that which subserves the processing of actual sensory input. Moreover, this study indicates that activation of primary somatosensory cortex can be obtained without intra-modal sensory input. These findings suggest that anticipation may invoke a tonic top-down regulation of neural activity.

关键词：认知/生理学扣带回/生理学磁共振成像神经网/生理学神经传导/生理学顶叶/解剖学和组织学顶叶/生理学知觉/生理学感知性防御物理刺激额叶前皮质/解剖学和组织学额叶前皮质/生理学休息/生理学躯体感觉皮质/解剖学和组织学躯体感觉皮质/生理学触觉/生理学成年人女(雌)性人类男(雄)性

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DIFFERENTIAL THALAMIC RELATIONSHIPS OF SENSORY-MOTOR AND PARIETAL CORTICAL FIELDS IN MONKEYS

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JOURNAL OF COMPARATIVE NEUROLOGY 1979年第4期183卷 833-881页

作者： JONES, EG WISE, SP COULTER, JD UNIV TEXAS MED BRANCH INST MARINE BIOMED GALVESTON TX 77550 USA

The thalamic connectivity of areas 3b, 1 and 2 of the 1st somatic sensory cortex (SI) and of the adjacent areas 4, 3a and 5 was studied in monkeys [Macaca fascicularis, M. mulatta and Saimiri sciureus] with anterograde and retrograde labeling techniques. Anteroposterior sectors of the SI cortex are represented in the thalamic ventrobasal complex by curved lamellae of thalamocortical relay cells extending through the dorsoventral and anteroposterior dimensions of the ventrobasal complex. Within such a lamella there are clustered aggregations of cells each projecting to a punctate zone of SI. Such cortical zones are < 1 mm in circumference and are interpreted as comparable to the columns of electrophysiological studies. Sectors of SI extending from posterior to anterior across areas 2 and 1 and others extending from posterior to anterior across area 3b, are each represented systematically across the full dorsal to ventral dimension of the ventrobasal complex. This implies at least 2 separate representations of the body surface: one in areas 2 and 1, and another in area 3b. Within a lamella of the ventrobasal complex, aggregations of cells projecting to areas 2 and 1 are mingled with those projecting to area 3b. Measurements of the sizes of retrogradely labeled cells in brains in which areas 2 and 1 or area 3b were separately injected showed no distinction between cells projecting to the 3 areas on the basis of size. Experiments combining retrograde cell degeneration due to ablation of area 3b with retrograde labeling after injection of areas 1 and 2 indicated little possibility of collateral projections to the 3 areas from the same cell. Area 3a has connectional relationships that strongly suggest it to be part of the motor cortex, area 4. Area 4 is connected with the oral division of the ventroposterolateral nucleus and with the caudal nucleus of the ventral lateral complex. These cellular groupings are only artificially separated and appear to form part of the same

关键词：脑图大脑皮质/解剖学和组织学类人猿亚目成束猴恒河猴运动皮质/解剖学和组织学顶叶/解剖学和组织学松鼠猴属躯体感觉皮质/解剖学和组织学丘脑核/解剖学和组织学动物

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CORTICAL-THALAMIC RELATIONSHIPS IN RAT

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EXPERIMENTAL NEUROLOGY 1975年第3期47卷 448-458页

作者： DONALDSON, L HAND, PJ MORRISON, AR UNIV PENN LABS ANATPHILADELPHIAPA 19174 UNIV PENN SCH VET MEDPHILADELPHIAPA UNIV PENN INST NEUROL SCIPHILADELPHIAPA

Single electrolytic lesions were made in the ventrobasal or posterior thalamic nuclear complex of 12 rats with a microelectrode after having first recorded the activity evoked by light tactile stimulation of various body parts. Resultant cortical axonal degeneration was studied with the Fink-Heimer I technique. Lesions in a region of the ventrobasal complex responding to stimulation of contralateral mystacial vibrissae led to somatotopically organized degeneration in the barrel field of the first somatic sensory cortex (SI), i.e., caudoventral vibrissae were represented dorsocaudally in the barrel field while rostrodorsal vibrissae were represented in the rostroventral barrel field. Degenerating axons ascended through deep cortical layers in bundles and terminated densely on the cells of lamina IV, involving neurons within the core and walls of the barrels as well as those in septal areas between barrels. A lesion in a lateral portion of the ventrobasal complex, Emmers' ventrobasal complex SII area, which was responsive to bilateral stroking of the hairs of the rat's dorsum, produced degeneration caudal to and overlapping cortical SI, but not in SII. Lesions of the posterior complex led to axonal degeneration caudal to SI, overlapping both visual and auditory cortices. A lesion in the medial portion of the ventrobasal complex, the thalamic gustatory nucleus, resulted in dense degeneration in a region of cortex dorsal to the rhinal fissure at the rostrocaudal level of the middle cerebral artery. This study answers the question of the cortical target of a portion of Emmers' ventrobasal complex SII region and of the posterior complex and confirms the position of the gustatory area and somatotopic representation of mystacial vibrissae.

关键词：脑图大脑皮质/解剖学和组织学大脑皮质/生理学诱发电位神经变性神经通路神经元/生理学躯体感觉皮质/解剖学和组织学躯体感觉皮质/生理学立体定位技术丘脑核/解剖学和组织学丘脑核/生理学动物大鼠

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EVIDENCE FOR 2 ORGANIZATIONAL PLANS WITHIN THE SOMATIC SENSORY-MOTOR CORTEX OF THE RAT

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JOURNAL OF COMPARATIVE NEUROLOGY 1979年第3期183卷 647-663页

作者： DONOGHUE, JP KERMAN, KL EBNER, FF Neuroscience Section Brown Unversity Providence Rhode Island 02912

Previous electrophysiological mapping of somatic sensory (SI) and motor (MI) cortex in the rat showed that these functional regions are completely overlapping in the hindlimb (HL) area, partially separate in the forelimb area and completely separate in the face area. How the sensory and motor thalamic relay nuclei project onto separate or overlapping subdivisions of SI and MI cortex was shown. The experimental sequence involved physiological mapping of 1 subdivision of SI or MI cortex and then injecting horseradish peroxidase (HRP) as a retrograde cell marker to back-fill the thalamic neurons that project to the identified area of cortex. The central issue was to compare the projections of the lemniscal-recipient ventrobasal nucleus (VB) and the cerebellar-recipient ventrolateral nucleus (VL) to the hindlimb and face subdivisions of SI and MI cortex. Various workers have divided the ventral nucleus differently using Nissl-stained transverse sections through the thalamus. 3H-amino acids were also injected into the deep cerebellar nuclei and the distribution of cerebellar fiber terminals in the ventral nucleus was used as another criterion to identify the border between VB and VL. Following HRP injections in physiologically identified HL cortex, labeled neurons were present in both VB and VL. Face area SI injections back-filled cells in VB (but not VL), while face area MI injections back-filled cells in VL (but not VB). Neurons in the intralaminar nuclei and the posterior nuclear complex were labeled after all injections. SI and MI cortex in the rat shows a combination of overlapping and separated plans of organization. In the Virginia opossum overlap is present in all subregions of SI and MI cortex, while the rhesus monkey shows separation of these areas. Different mammals have evolved different degrees of separation of SI and MI cortex. In every case where there is evidence of sensory and motor overlap, there is anatomical convergence of VB and VL projections to tha

关键词：脑图小脑核/解剖学和组织学面部/神经支配类人猿亚目后肢/神经支配哺乳动物/解剖学和组织学运动皮质/解剖学和组织学神经通路/解剖学和组织学躯体感觉皮质/解剖学和组织学丘脑核/解剖学和组织学动物大鼠

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