THE EFFECTS OF AWARENESS ON CORTICAL EVOKED POTENTIALS TO CONDITIONED AFFECTIVE STIMULI

A previous paper of ours (Begleiter, Gross, & Kissin, 1967) demonstrated that it was possible to condition affective meaning to meaningless figures (CS), and significantly alter visual evoked potential (VEP) amplitudes and latencies to them, without the S's awareness of the CS–UCS relationship (Experiment I, totally unaware). In the present study some Ss were deliberately informed that a CS–UCS connection existed; however, the exact nature of their relationship was not divulged (Experiment II, slightly aware). Other Ss were explicitly informed of the correct CS–UCS contingency, and entire conditioning paradigm (Experiment III, fully aware). One physiological (VEP) and two behavioral (interflash interval and semantic differential) indices of conditioning were obtained during an extinction procedure, and demonstrated significant differences between CRs in Experiment II, but none in Experiment III. VEP amplitudes to positive and negative CSs were enhanced in Experiment II, and suppressed in Experiment I, in comparison to the neutral CS. This effect was most marked in responses to the negative CS. It is suggested that level of awareness of the CS–UCS contingency might be reflected in our physiological index of conditioning - VEP amplitude.