Nonaware classical conditioning to pictorial facial stimuli in a between-groups paradigm

Abstract

The present experiment investigated the effects of aware and nonaware modes of extinction in classical conditioning to facial emotional stimuli. The subjects participated in three different experimental phases. In the first (habituation) phase they were presented with a 500 ms angry face. In the second (acquisition) phase, for half of the subjects the 500 ms face was paired with an aversive noise (experimental group) while for the other half of the subjects the face and the noise presentations were separated by 6-10 s intervals (sensitization control group). In the third (extinction) phase, these two groups were further divided into two subgroups. One subgroup of both the experimental and control group had the face stimulus presented for 30 ms, and immediately masked with a neutral picture. The other two subgroups had the face presented for 500 ms with no mask. The results showed that conditioning only occurred in the experimental subgroups which was indicated by a significant difference between skin conductance responses during habituation and corresponding responses during extinction. Secondly, comparing the experimental and control groups during the extinction phase, a significant conditioning effect was observed for both the aware and nonaware masked modes of extinction for the experimental group. The results suggest that conditioned autonomic responses may be elicited in a nonaware mode.

Strength of visual percept generated by famous faces perceived without awareness: Effects of affective valence, response latency, and visual field

“…There is much evidence that facial expressions can be detected pre-consciously and can influence psychophysiological and behavioural responses without awareness of the particular expression (e.g., Dimberg & Ohman, 1996;Dimberg, Thunberg, & Elmehed, 2000;Johnsen & Hugdahl, 1991Mogg & Bradley, 1999;Murphy & Zajonc, 1993;Niedenthal, 1990;Ohman, Esteves, & Soares, 1995;Robinson, 1998;Saban & Hugdahl, 1999;Whalen et al, 1998;Wong, Shevrin, & Williams, 1994). All of these studies presented masked faces for very brief exposure duration (target-to-mask stimulus onset asynchrony [SOA] of less than 35 ms).…”

Unequally masked: Indexing differences in the perceptual salience of "unseen" facial expressions

“…Backward visual masking entails the presentation of a masking stimulus in such a way as to disrupt the processing of a previously presented target image. Given the increasing and widespread interest in clarifying the roles of awareness and automatic processes in the appraisal and generation of emotion (Robinson, 1998;LeDoux, 1996;Niedenthal, 1990;Mogg & Bradley, 1999) and autonomic activity (Saban & Hugdahl, 1999;Wong et al, 1994;O È hman & Soares, 1998), backward visual masking has proved extremely valuable for investigations in the affective domain.…”

Angry and happy faces perceived without awareness: A comparison with the affective impact of masked famous faces

“…Dimberg & Ohman, 1996;Dimberg, Thunberg & Elmehed, 2000;Johnsen & Hugdahl, 1991;1993;Mogg & Bradley, 1999;Murphy & Zajonc, 1993;Niedenthal, 1990;Ohman, Esteves & Soares, 1995;Robinson, 1998;Saban & Hugdahl, 1999;Whalen, Rauch, Etcoff, McInerney, Lee & Jenike, 1998;Wong, Shevrin & Williams, 1994). All of these studies presented masked faces for very brief exposure duration (target-to-mask stimulus onset asynchrony of less than 35ms).…”