A Comparative Investigation Of Erp Components And The Scr In A Habituation And Dishabituation Paradigm

The present experiment investigated the trial-by-trial habituation in the event-related potential (ERP) and the skin conductance response (SCR) to repeated stimuli and dishabituation to rare stimuli. In a balanced design, two groups of subjects passively observed either large black discs as repeated stimuli and small as rare, or vice versa. No consistent effects of stimulus size were obtained between the groups. Late positivity was composed of a double peak at Cz, containing contributions from P3a and P300; the latter only was observed at Pz. The SCR and P3a and P300 at Cz demonstrated habituation, but not the N100 or P200, nor the P300 at Pz. Rare stimuli elicited an enhancement, albeit nonsignificant, in SCR amplitude only. No dishabituation of any of the responses by these stimuli was observed. The SCR correlated significantly with late positivity at Cz and Pz. Discussion focuses on SCR and late positivity as OR components.