title: The relationship in gating effects between short-latency and long-latency somatosensory-evoked potentials.
abstract: We investigated the relationship between short-latency and long-latency somatosensory-evoked potentials (SEPs) relating to voluntary movement. In general, the amplitudes of short-latency components in SEPs are attenuated during movement, whereas those of long-latency are enhanced, and this phenomenon is termed 'gating effects'. This study aimed to examine the relationship of changes in amplitude between short-latency and long-latency SEPs. SEPs were recorded from 11 participants at Fz, Cz, Pz, and C4' by stimulating the left median nerve. Two tasks were conducted; Control and Movement. In Control, the participant was asked to relax with no specific task. In Movement, the participant was encouraged to continue a rapid drumming motion of all fingers of the left hand at a self-paced rate. The amplitudes of short-latency SEPs, the P25 at C4' and N30 at Fz, were significantly smaller in the Movement than Control condition. By contrast, the amplitudes of long-latency SEPs, the N140 at Fz, Cz, and Pz were significantly larger in Movement than Control condition. Moreover, a significant positive correlation was observed in the rate of amplitude change between the frontal N30 and vertex N140, indicating that for the participants with a frontal N30 of smaller amplitude during Movement, the amplitude of the vertex N140 was smaller. We inferred that the neural activities in movement-related cortices affected the sources for the frontal N30 and vertex N140 in the same neuronal network simultaneously.
authors: Department of Integrative Physiology, National Institute for Physiological Sciences, Okazaki, Japan. nakata@aoni.waseda.jp
authors: Hiroki
authors: H
authors: Nakata
authors: Kiwako
authors: K
authors: Sakamoto
authors: Masato
authors: M
authors: Yumoto
authors: Ryusuke
authors: R
authors: Kakigi
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D004558:Electric Stimulation; D004569:Electroencephalography; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009068:Movement; D011930:Reaction Time / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology*; D013223:Statistics as Topic; D013997:Time Factors; D055815:Young Adult