Visual attention and driving behavior of male autistic individuals while encountering driving hazards: A driving simulator study

Abstract

Hazard perception is an important aspect of driving competence that significantly contributes to road safety. Allocating sufficient visual attention to hazards and responding accordingly can help reduce the likelihood of road crashes. Although hazard perception has been investigated to some extent in autistic individuals, little attention is given to hazards for which attention has to be divided among different hazard sources. The current study assessed visual attention and driving behavior of autistic individuals to hazards, including dividing and focusing attention (DF), environmental prediction (EP), and behavioral prediction (BP) hazards. A total of 53, male participants, 19 autistic and 34 non-autistic individuals participated in the study. All participants completed a driving simulator scenario while wearing an eye-tracking system. The included eye-tracking measures were time to first fixation (TTFF), frequency count (FC), first fixation duration (FFD), and average fixation duration (AFD). The included driving measures were brake reaction time (BRT), minimum time-to-collision (minTTC), and speed change immediately before encountering the hazard. A self-reported appraisal regarding difficulty in managing hazards was also included. A series of Linear Mixed Models (LMM) were computed to assess the effects of participant group (autistic and non-autistic) and hazard types (DF, EP and BP) on the included measures. Comparisons of visual attention between autistic and non-autistic participants when responding to hazards yielded mixed results. For certain hazards, autistic participants demonstrated faster fixation (e.g., DF and BP). In contrast, for other hazards, non-autistic participants exhibited quicker fixation (e.g., EP) and longer average fixation duration (e.g., DF and EP). For some hazards, however, both groups displayed comparable levels of average fixation duration (e.g., BP). Although variations in visual attention to hazards were observed between autistic and non-autistic individuals, these differences did not manifest in driving performance metrics. This is evidenced by the absence of significant interactions between participant groups and hazard types concerning driving measures. However, autistic individuals were more likely to experience crashes involving BP hazards than non-autistic individuals. Notably, inexperienced autistic participants had a higher crash rate on BP hazards compared to non-licensed non-autistic participants. In contrast, the crash rates were comparable between licensed participants in both groups. The study may reflect that pre-driver autistic participants could benefit from hazard perception training, particularly in dealing with BP hazards.