Human reactions to physical stimulus and the removal of such stimulus as recorded by magnetoencephalography.

摘要

We studied the cortical evoked fields elicited by the examiner's touch on glabrous skin of the subject's index finger. Two main components of evoked fields were elicited, and these dipoles were located in the primary somatosensory cortex contralateral to the side of the subject's index finger touched by the examiner. When the timing of removal of the examiner's finger triggered the data acquisition using the photosensor, the strength of the dipole from early evoked fields was stronger than that from late ones. We showed that these evoked fields were elicited by removal and touch of the examiner's finger respectively in response to the mechanical compression and decompression of the skin.