PLoS One. 2016 Sep 13;11(9):e0162689. doi: 10.1371/journal.pone.0162689.

Unconscious Processing of Facial Emotional Valence Relation: Behavioral Evidence of Integration between Subliminally Perceived Stimuli.

Liu C1, Sun Z2, Jou J3, Cui Q4, Zhao G5, Qiu J2, Tu S1.

1 Department of Psychology, Institute of Education, China West Normal University, Nanchong 637002, China.

2 Faculty of Psychology, Southwest University, Chongqing 400715, China.

3 Department of Psychological Science, University of Texas-Rio Grande Valley, Edinburg, TX, 78539, United States of America.

4 School of Political Science and Public Administration, University of Electronic Science and Technology of China, Chengdu, 610054, China.

5 School of psychology, Liaoning Normal University, Dalian, 116029, China.



Although a few studies have investigated the integration between some types of unconscious stimuli, no research has yet explored the integration between unconscious emotional stimuli. This study was designed to provide behavioral evidence for the integration between unconsciously perceived emotional faces (same or different valence relation) using a modified priming paradigm. In two experiments, participants were asked to decide whether two faces in the target, which followed two subliminally presented faces of same or different emotional expressions, were of the same or different emotional valence. The interstimulus interval (ISI) between the prime and the target was manipulated (0, 53, 163 ms). In Experiment 1, prime visibility was assessed post-experiment. In Experiment 2, it was assessed on each trial. Interestingly, in both experiments, unconsciously processed valence relation of the two faces in the prime generated a negative priming effect in the response to the supraliminally presented target, independent of the length of ISI. Further analyses suggested that the negative priming was probably caused by a motor response incongruent relation between the subliminally perceived prime and the supraliminally perceived target. The visual feature incongruent relation across the prime and target was not found to play a role in the negative priming. Because the negative priming was found at short ISI, an attention mechanism as well as a motor inhibition mechanism were proposed in the generation of the negative priming effect. Overall, this study indicated that the subliminal valence relation was processed, and that integration between different unconsciously perceived stimuli could occur.

PMID: 27622600

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