INTERACTION BETWEEN AFFERENT INPUT FROM FINGERS IN HUMAN SOMATOSENSORY CORTEX
INTERACTION BETWEEN AFFERENT INPUT FROM FINGERS IN HUMAN SOMATOSENSORY CORTEX
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DOI：
10.1016/0006-8993(95)00424-o
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发表时间：
1995-07-10
期刊：
影响因子：
2.9
通讯作者：
HARI, R
中科院分区：
文献类型：
--
作者：
FORSS, N;JOUSMAKI, V;HARI, R
我们用122通道全头皮SQUID磁强计记录了8名健康受试者的体感诱发磁场。刺激序列包括“标准”刺激（85%）提供给手掌侧的左手拇指与刺激间隔为0.6秒和“偏差”（15%），随机穿插在标准，小指，反之亦然。两种刺激都激活了四个来源区域：对侧初级躯体感觉皮层（SI），对侧和同侧次级躯体感觉皮层（SII）和对侧后顶叶皮层（PPC）。短潜伏期（20-40 ms）反应起源于SI皮层，而长潜伏期反应则起源于所有4个区域。在SII和PPC，偏差刺激引起更大的反应时，单独提出，没有干预的标准，比之间的标准。这意味着来自两个手指的传入冲动之间的相互作用和/或部分混合的皮层代表。我们的研究结果表明，在协议与动物的数据，不同的兴奋/抑制平衡在不同的躯体感觉区。
We recorded somatosensory evoked magnetic fields from eight healthy subjects with a 122-channel whole-scalp SQUID magnetometer. The stimulus sequence consisted of 'standard' stimuli (85%) delivered to palmar side of the left thumb with an interstimulus interval of 0.6 s and of 'deviants' (15%), randomly interspersed among the standards, to little finger, and vice versa. Both stimuli activated four source areas: the contralateral primary somatosensory cortex (SI), the contra-and ipsilateral secondary somatosensory cortices (SII), and the contralateral posterior parietal cortex (PPC). The short-latency (20-40 ms) responses originated in the SI cortex, whereas long-latency responses arose from all 4 areas. At SII and PPC, the deviant stimuli elicited larger responses when presented alone, without intervening standards, than among standards. This implies interaction between afferent impulses from the two fingers and/or partly intermingled cortical representations. Our findings show, in agreement with animal data, different excitatory/inhibitory balance in the various somatosensory areas.