Hamada Y, Kado H, Suzuki R
Human Information System Laboratories, Kanazawa Institute of Technology, Matto, Ishikawa 924-0838, Japan.
Clin Neurophysiol. 2001 Jul;112(7):1326-33. doi: 10.1016/s1388-2457(01)00542-9.
To elucidate the temporal profile of interactions between sensory information from both hands in the somatosensory cortex.
Somatosensory evoked fields (SEFs), generated by stimulation applied to the right index finger after a preceding stimulation to the left index finger, were recorded using a whole head-type magnetoencephalography (MEG). The paired electrical stimuli were applied with a stimulation onset asynchrony (SOA) of 50, 100, 200, 300, or 400 ms.
The mean SEF intensities in the primary somatosensory area (SI) of five subjects, which were evoked approximately 40 ms after the latter of the paired stimuli, were not significantly smaller than that evoked in the control condition when only the right finger was stimulated. In contrast, SEFs in the secondary somatosensory area (SII), generated approximately 100 ms after the stimuli, were suppressed when the paired stimuli were applied at an SOA of 100 ms (P<0.05, t test). In addition, SEFs at approximately 150 ms after the stimuli were significantly suppressed at SOAs of 50, 100 (P<0.05), 200, and 300 ms (P<0.1).
Within a time window of approximately 300 ms, sensory information from the left finger significantly affected the SEFs generated by sensory inputs from the right finger. This time window may be required for the integration of sensory input.
阐明体感皮层中来自双手的感觉信息之间相互作用的时间特征。
使用全头型脑磁图（MEG）记录在先前刺激左手食指后刺激右手食指所产生的体感诱发电场（SEF）。成对的电刺激以50、100、200、300或400毫秒的刺激起始异步（SOA）施加。
五名受试者初级体感区（SI）中，在成对刺激中的后者之后约40毫秒诱发的平均SEF强度，并不显著小于仅刺激右手手指时在对照条件下诱发的强度。相比之下，在刺激后约100毫秒产生的次级体感区（SII）中的SEF，当以100毫秒的SOA施加成对刺激时受到抑制（P<0.05，t检验）。此外，在刺激后约150毫秒时的SEF在50、100（P<0.05）、200和300毫秒的SOA下受到显著抑制（P<0.1）。
在大约300毫秒的时间窗口内，来自左手手指的感觉信息显著影响了由来自右手手指的感觉输入所产生的SEF。这个时间窗口可能是感觉输入整合所必需的。
