Abstract
Goal: To investigate the interplay between orienting eye movements and emotional judgment. Traditionally, emotional judgement is believed to be independent of bodily movements, or to influence them, but not vice versa. Method: We measured eye movements in subjects who inspected pairs of human faces freely to make a forced-choice decision. They had to decide, in separate sessions which face was: (1)more attractive (emotional judgement), (2) less attractive (emotional judgement), or (3) more round (objective decision) and to press one of two keys. Faces were shown until subjects reached their decision. Analysis: Inspection times were divided into time bins of 400 ms. The analysis aimed to establish the existence (if any) of a correlation between inspection times of faces and the subjects' emotional or objective judgements. Such correlation would imply a modulation of judgements by eye movements. Results: Significant correlation was found between the total looking times and choice in the “more attractive” condition, but not in the “less attractive” and the “more round” conditions. Subjects inspected longer the face that they indicated later as more attractive in the majority of trials (P<0.002, total gaze time). Also, the percentage of time that the chosen face was inspected increased from chance (50%) to a significant level (average 76%, p<0.009) as subjects approached decision. This indicates a positive feedback mechanism in attractiveness decisions, where eye movements may modulate the following emotional judgement. Neither of the other two conditions, i.e. less attractive and more round, rendered a significant correlation. Discussion: (1) Liking may be a special subjective decision, since disliking does not seem to be its opposite, as it semantically is. (2) Natural emotional decisions may have a strong somatic component, i.e. they may be influenced by orienting bodily movements such as eye movements, as implied in preferential looking phenomenon in infants, rather than relying exclusively on mental “attractiveness criteria”. (3) This effect seems to be limited to natural emotional judgements, because an unnatural emotional task (disliking) and a rather objective task (roundness) did not show significant trends.
Supported by California Institute of Technology.