An examination of EEG component of ERP at drink image display

Abstract

This study is to examine the event-related potential(ERP) relating the intention("I want to drink") to "with/without speech-imagery" when drink-images are displayed on the PC screen. An experimental process was set in 8s as followings; fixation-image display(1s), drink-image display(2.5s), intention check(1.5s), fixation-image display(1s), and speech-imagery period(2s). It was repeated 100-times. The ERP were measured with 10-20 system in a magnetically-shielded room with BPF(0.08-100Hz) and notch-filter(50Hz) for 10-subjects. In the analysis, it was averaged with 35-trials selecting by "with/without speech-imagery" in an epoch(fixation-image display and speech-imagery) of 3s and time-frequency analysis was done. Event-related synchronization(ERS) and desynchronization were examined with t-test. The ERS were observed in α-band on the left-hemisphere in case of "with speech-imagery" for latency of 500-1500ms and the significant differences(p<0.05) were shown in the left-hemisphere and occipital-region. It is suggested the useful information of selecting electrode positions to detect the ERP for judgment of "with/without speech-imagery" in the intention.