Emotion facilitates perception and potentiates the perceptual benefits of attention

Abstract

Does emotion affect how people see? We investigated the effects of emotion and attention, as well as their conjoint effect, on contrast sensitivity, a dimension of early vision. We manipulated the emotional valence and the attentional distribution of cues preceding a target stimulus and asked observers to judge the orientation of the target as contrast varied. This study provides the first behavioral evidence that (a) emotion enhances contrast sensitivity irrespective of attention and (b) emotion potentiates the effect of attention on contrast sensitivity.

Fig. 1

Sequence of events in a trial and illustration of cue types. In Experiment 1, each trial contained a fearful or neutral face at the center of the screen. Shortly after presentation of this cue, four gratings were flashed—a tilted target and three vertical distractors. Observers performed a two-alternative forced-choice orientation discrimination task (left vs. right) for the target. The trial sequence and task in Experiment 2 were similar, except that the cue preceding the target was either peripheral (attracting covert attention) or distributed (baseline). ISI = interstimulus interval.

Fig. 2

Contrast psychometric functions from Experiment 1: observers' average accuracy as a function of the stimulus contrast level for trials with upright faces as cues (top) and trials with upside-down faces as cues (bottom). The averaged functions reflect the general performance of all observers. Error bars correspond to the average ±1 standard error for each condition.

Fig. 3

Contrast-sensitivity ratios for the 6 observers in Experiment 2 (upright faces). The ratio between contrast sensitivity following a fearful face and contrast sensitivity following a neutral face is shown separately for the peripheral-cue and distributed-cue conditions. A ratio of 1 would indicate no difference between the fearful and neutral conditions; values greater than 1 indicate that fearful faces improved contrast sensitivity more than neutral faces.

Fig. 4

The impact of emotion and attention on perception. The gratings shown represent the contrast threshold (i.e., the contrast necessary to perform the orientation discrimination task at 82% accuracy) in each condition: fearful face, peripheral cue (a); neutral face, peripheral cue (b); fearful face, distributed cue (c); and neutral face, distributed cue (d).