TY  - JOUR
PY  - 1999//
TI  - P300 and response selection: a new look using independent-components analysis
JO  - Brain topography
A1  - Pritchard, W. S.
A1  - Houlihan, M. E.
A1  - Robinson, J. H.
SP  - 31
EP  - 37
VL  - 12
IS  - 1
N2  - PURPOSE: The most prevalent current view of the functional role of the P300 component of the event-related potential (ERP) is that it indexes strategic processing related to context updating. Using independent-components analysis (ICA), the present study examined the role of P300 in the tactical process of response selection. METHODS: In a task crossing manipulations of perceptual difficulty (PD) and response-selection difficulty (R-SD), ICA was employed to measure not only P300 latency, but its onset and duration as well. RESULTS: Increased PD delayed P300 latency and onset in parallel, while increased R-SD lengthened P300 duration. CONCLUSIONS: The latency and onset results suggest that the often-cited covariation of P300 latency with stimulus-evaluation time is secondary to effects on processing stages preceding P300. The results for duration indicate that P300 is involved in response selection, suggesting that it is not a unitary phenomenon. While P300's well-known relation to stimulus probability indicates a strategic role, our findings indicate a tactical role as well.<p /> <p>Language: en</p>
LA  - en
SN  - 0896-0267
UR  - http://dx.doi.org/
ID  - ref1
ER  -