Potentials associated with the Go/No-Go paradigm in traumatic brain injury

Abstract

Surface event-related potentials associated with visually triggered movements (Go) and the inhibition of planned movements (No-Go) were examined in seven healthy subjects and five postacute traumatic brain injured (TBI) subjects. Analysis showed that the cortical potential P1-N1 was similarly affected by condition in both the control and TBI groups. Although TBI subjects showed smaller P1-N1 amplitudes (Go = 2.91uV; No-Go = 3.95uV; p < .03) relative to control subjects (Go = 4.82uV; No-Go = 6.03uV; p < .03), both groups showed larger amplitudes in the No-Go condition. A bipolar lead (C3′-C3″) over the sensorimotor cortex showed a reversal of polarity between Go and No-Go conditions which was synchronized with the EMG activity in all control subjects. This signal reversal and timing of potentials was absent in four of the five TBI subjects' waveforms, suggesting difficulty in sensorimotor processes associated with movement control. In addition, TBI subjects displayed a number of atypical stimulus-locked waveforms, which are discussed relative to the specific functional impairments of individual subjects. The results highlight the potential usefulness of such paradigms as the Go/No-Go procedure in the analyses of electroencephalographic waveforms and of the effects of TBI.