Cortical potentials related to the nogo decision

Citation
Sr. Filipovic et al., Cortical potentials related to the nogo decision, EXP BRAIN R, 132(3), 2000, pp. 411-415
Citations number
18
Categorie Soggetti
Neurosciences & Behavoir
Journal title
EXPERIMENTAL BRAIN RESEARCH
ISSN journal
00144819 → ACNP
Volume
132
Issue
3
Year of publication
2000
Pages
411 - 415
Database
ISI
SICI code
0014-4819(200006)132:3<411:CPRTTN>2.0.ZU;2-3
Abstract
The go/nogo reaction time task has been frequently used to assess volitiona l inhibition. Psychophysiological studies of the correlates of the go/nogo decision have almost exclusively been concerned with N2 and P3 potentials o f the event-related potentials (ERPs). However, in studies where the EMG on set latency was available, it was obvious that this latency was shorter tha n or at least equal to the latencies of the studied cerebral potentials. In this study, by concurrent recording of the EEG and EMG activity we aimed t o better define the temporal relationship between cortical activity and mot or response. Particularly, we wanted to identify the early (i.e. pre EMG-on set) electrophysiological correlates of the nogo decision. We used a modifi ed S1-S2 paradigm that involved a two-stage go/nogo decision. In this task both S1 and S2 were informative and required the subject to make a decision , but the nature of the decision differed. The decision at SI involved whet her to prepare a movement, whereas the decision at S2 involved whether to i nitiate or inhibit an already prepared response. To better visualise the no go decision related components of the ERPs, the go ERPs were subtracted fro m the corresponding nogo ERPs and difference ERPs were formed. Before EMG o nset, a small negative component common to both go/nogo difference traces a nd corresponding roughly with the N1 wave was detected. It is suggested tha t this early negativity may be a more specific electrophysiological reflect ion of the nogo decision proper.