Working Memory Capacity and Executive Attention as Predictors of Distracted Driving

The present study empirically examined the effects of working memory capacity (WMC) and executive attention on distracted driving. Study 1 examined whether a Grocery List Task (GLT) distractor would load onto WMC. Forty-three participants completed a series of WMC tasks followed by the GLT. They then completed two driving trials: driving without the GLT and driving while completing the GLT. It was hypothesized that WMC would positively correlate with GLT performance. A bivariate correlation indicated that WMC was positively associated with performance on the GLT. Study 2 tested a series of distractor tasks (GLT, Tone Monitoring, and Stop Signal) to examine whether these three distractor tasks were also related to WMC, and if each of the distractor tasks would result in poor driving performance. Eighty-four participants were randomly assigned to the distractor conditions. Results indicated that GLT was related to WMC, but Tone Monitoring was not related to WMC. Also, engaging in each of the three distractor tasks led to significantly poorer driving performance. Study 3 evaluated whether rainy or clear weather conditions would affect the relationship between WMC and distracted driving using the same three distractor tasks (GLT, Tone Monitoring, and Stop Signal) as used in Study 2. Ninety-six participants were randomly assigned to the distractor conditions. Results showed that engaging in GLT while driving led to slower braking response times compared to not engaging in GLT driving while driving. Furthermore, WMC moderated the degree to which distraction impaired performance. The present findings clearly indicate that all three distractor tasks had a deleterious effect on driving performance. Furthermore, this effect of distraction on driving depends on many factors, including the type of distraction, the driving performance measure, and the individual\u27s cognitive capabilities. Both theoretical and practical implications are discussed and directions for future research are presented