[Modulation of evoked potentials following electrical tooth and finger stimulation at selective attention task]

To investigate the effect of attention and novelty change of stimulus, modulation of evoked potentials following electrical tooth stimulus (EP-TS) and finger stimulus (EP-FS) by selective attention task were studied in 17 healthy adult volunteers. Stimulus in this study were electrical tooth and finger stimulus, tone beep in constant (2.0 sec.) interval in random order, and delivering percentage of tooth and finger stimulus was 10, 20, 30, 40, and 50% and tone beep was 80, 60, 40, 20, and 0%. The results were as follows: 1) P2 latency and N 2-P2 amplitude were increased while the subject's attention was toward each stimulus (attention), decreased while the subject's attention was not toward each stimulus (non-attention) at EP-TS and EP-FS. 2) When paying attention, P 2 latency and N 2-P 2 amplitude were increased as delivering percentage of tooth and finger stimulus were decreased. These findings suggested that attention and novelty change of stimulus when paying attention were one of the factors that influence psychological factors and modulate EP-TS and EP-FS results.