Temporal course of attention bias toward emotional faces in individuals with autistic traits: an eye-movement study

Abstract

Introduction: Similar attention patterns have been found in individuals with autism spectrum disorder (ASD) and autistic traits (ATs). The Intense World Theory and previous studies suggest that individuals with ASD may demonstrate a vigilance-avoidance attention pattern toward emotional faces. However, the attention patterns in individuals with ATs remain unclear. Therefore, this study employs eye-tracking technology to examine the characteristics and temporal course of attention bias toward emotional faces in individuals with ATs.

Methods: The Autism-spectrum Quotient (AQ) was used to evaluate the level of ATs among 2,502 college students. A total of 50 participants were selected from the 2,502 college students: 25 high-AQ group participants were randomly selected from the 10% of individuals with the highest AQ scores. Similarly, 25 low-AQ group participants were randomly selected from the 10% of participants with the lowest AQ scores. All selected participants completed an eye-tracking study while performing a dot-probe task with emotional faces (positive-neutral, negative-neutral, and negative-positive). By analyzing data from different time periods, the attention bias and time course of individuals with ATs toward emotional faces were investigated.

Results: The results show that compared to the low-AQ group, the high-AQ group detected negative faces faster in the early stages of emotional face processing. As the presentation time of emotional faces increased (at the 2-3 s mark), the fixation scores for negative-neutral faces of the high-AQ group were less than 0.5, which was significantly lower than those of the low-AQ group. Meanwhile, the high-AQ group showed brief attentional avoidance toward positive emotion at 3-4 s in the positive-neutral trials, indicating that the high-AQ group exhibited attention avoidance to both negative and positive faces during the middle and later stages of emotional processing.

Conclusion: This study suggests that individuals with ATs display a vigilance-avoidance pattern toward emotional faces. It contributes to a deeper understanding of the mechanisms of attention in persons with ATs and further supports the Intense World Theory.

Keywords: attention bias; autism spectrum disorder; autistic traits; eye movement; temporal course.

Figure 1

Flowchart describing the experimental design. All pictures in the experiment were selected from the Chinese facial affective picture system (Bai et al., 2005). During each trial, the order in which emotion combinations (positive-neutral, negative-neutral, negative–positive) were presented was random, and the positions of different emotion pictures in each combination were balanced.

Figure 2

The bar charts and fixation trajectory graphs of first fixation scores made by groups in different facial expression pairs. Data in the bar charts are expressed as Mean ± SE. *: p < 0.05. (A) The first fixation scores of three Expressions. (B) The fixation trajectory graphs show the fixation trajectories of two groups of participants during 0–1 s in the negative-positive pairs trials, and the numbers in the circle indicate the order of the fixation count, with negative facial expression on the left and positive facial expression on the right.

Figure 3

Line charts of participants’ fixation duration scores and fixation count scores in the different expression pair trials. The numbers 1–8 in the figure represent the scores of stimuli during 0–1 s, 1–2 s, 2–3 s, 3–4 s, 4–5 s, 5–6 s, 6–7 s, and 7–8 s, respectively. Data in the line charts are expressed as Mean ± SE.*: p < 0.05. (A) The scores of in the positive-neutral expression pair trials. (B) The scores of in the negative-neutral expression pair trials. (C) The scores of in the negative-positive expression pair trials.

Figure 4

Fixation duration hotspot graph of participants in the different conditions. (A) The left side shows a neutral facial expression, and the right side shows a negative facial expression. (B) The left side shows a neutral facial expression, and the right side shows a positive facial expression.