James R. Coleman

Assessing cognitive distraction in the automobile

Objective: The objective was to establish a systematic framework for measuring and understanding cognitive distraction in the automobile. Background: Driver distraction from secondary in-vehicle activities is increasingly recognized as a significant source of injuries and fatalities on the roadway. Method: Across three studies, participants completed eight in-vehicle tasks commonly performed by the driver of an automobile. Primary, secondary, subjective, and physiological measures were collected and integrated into a cognitive distraction scale. Results: In-vehicle activities, such as listening to the radio or an audio book, were associated with a low level of cognitive workload; the conversation activities of talking to a passenger in the vehicle or conversing with a friend on a handheld or hands-free cell phone were associated with a moderate level of cognitive workload; and using a speech-to-text interfaced e-mail system involved a high level of cognitive workload. Conclusion: The research established that there are significant impairments to driving that stem from the diversion of attention from the task of operating a motor vehicle and that the impairments to driving are directly related to the cognitive workload of these in-vehicle activities. Moreover, the adoption of voice-based systems in the vehicle may have unintended consequences that adversely affect traffic safety. Application: These findings can be used to help inform scientifically based policies on driver distraction, particularly as they relate to cognitive distraction stemming from the diversion of attention to other concurrent activities in the vehicle.

Working Memory's Workload Capacity

We examined the role of dual-task interference in working memory using a novel dual two-back task that requires a redundant-target response (i.e., a response that neither the auditory nor the visual stimulus occurred two back versus a response that one or both occurred two back) on every trial. Comparisons with performance on single two-back trials (i.e., with only auditory or only visual stimuli) showed that dual-task demands reduced both speed and accuracy. Our task design enabled a novel application of Townsend and Nozawa’s (Journal of Mathematical Psychology 39: 321–359, 1995) workload capacity measure, which revealed that the decrement in dual two-back performance was mediated by the sharing of a limited amount of processing capacity. Relative to most other single and dual n-back tasks, performance measures for our task were more reliable, due to the use of a small stimulus set that induced a high and constant level of proactive interference. For a version of our dual two-back task that minimized response bias, accuracy was also more strongly correlated with complex span than has been found for most other single and dual n-back tasks.

The smartphone and the driver’s cognitive workload: A comparison of Apple, Google, and Microsoft’s intelligent personal assistants.

The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple’s Siri, Google’s Google Now for Android phones, and Microsoft’s Cortana) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive workload of drivers when they used the voice-based features of each smartphone to place a call, select music, or send text messages. Cognitive workload was derived from primary task performance through video analysis, secondary-task performance using the Detection Response Task (DRT), and subjective mental workload. We found that workload was significantly higher than that measured in the single-task drive. There were also systematic differences between the smartphones: The Google system placed lower cognitive demands on the driver than the Apple and Microsoft systems, which did not differ. Video analysis revealed that the difference in mental workload between the smartphones was associated with the number of system errors, the time to complete an action, and the complexity and intuitiveness of the devices. Finally, surprisingly high levels of cognitive workload were observed when drivers were interacting with the devices: “on-task” workload measures did not systematically differ from that associated with a mentally demanding Operation Span (OSPAN) task. The analysis also found residual costs associated using each of the smartphones that took a significant time to dissipate. The data suggest that caution is warranted in the use of smartphone voice-based technology in the vehicle because of the high levels of cognitive workload associated with these interactions. Le but de cette recherche consistait à examiner, au moyen de trois différents assistants personnels (Siri de Apple, Google Now de Google pour téléphone Androïde et Cortana de Microsoft), l’impact d’interactions vocales sur la charge de travail cognitive du conducteur. À l’aide de deux expériences employant un véhicule instrumenté sur des routes de banlieue, nous avons mesuré la charge de travail cognitive de conducteurs alors qu’ils utilisaient les fonctionnalités vocales de chacun des téléphones intelligents pour effectuer un appel, sélectionner de la musique ou envoyer un message texte. La charge de travail cognitive a pu être déterminée après évaluation de la performance de la tâche principale par analyse-vidéo, de la performance de la tâche secondaire par tâche de détection-réponse (DRT) puis, de la charge de travail mentale subjective. Nous avons constaté que la charge de travail y était nettement plus élevée que celle associée à la tâche simple de conduire. Il y avait aussi des différences systématiques entre les téléphones intelligents. Le système Google était moins demandant cognitivement sur le conducteur que les systèmes Apple et Microsoft, lesquels avaient le même effet. L’analyse vidéo a montré que la différence au niveau de la charge de travail mentale entre téléphones intelligents était associée au nombre d’erreurs de système, à la durée de temps requise pour mener à bien une action et à la complexité et à l’intuitivité des appareils. Finalement, des niveaux étonnamment élevés de charge de travail cognitive ont été observés lorsque les conducteurs étaient en interaction avec leurs appareils : Les mesures de la charge de travail associée à la concentration sur une tâche ne différaient pas systématiquement de celles associées à une tâche (OSPAN) exigeante sur le plan mental. L’analyse a aussi révélé la présence de coûts résiduels associée à l’utilisation de chacun des téléphones intelligents, lesquels ont pris un temps considérable pour se dissiper. Les données suggèrent que la prudence est de mise en ce qui a trait à l’utilisation de technologie vocale sur téléphone intelligent dans un véhicule étant donné les niveaux élevés de la charge de travail cognitive associée à ces interactions.

Working memory capacity and task goals modulate error‐related ERPs

The present study investigated individual differences in information processing following errant behavior. Participants were initially classified as high or as low working memory capacity using the Operation Span Task. In a subsequent session, they then performed a high congruency version of the flanker task under both speed and accuracy stress. We recorded ERPs and behavioral measures of accuracy and response time in the flanker task with a primary focus on processing following an error. The error-related negativity was larger for the high working memory capacity group than for the low working memory capacity group. The positivity following an error (Pe) was modulated to a greater extent by speed-accuracy instruction for the high working memory capacity group than for the low working memory capacity group. These data help to explicate the neural bases of individual differences in working memory capacity and cognitive control.

Cognitive Workload Using Interactive Voice Messaging Systems

The current research sought to understand the sources of cognitive distraction stemming from voice-based in-vehicle infotainment systems (IVIS) to send and receive textual information. Three experiments each evaluated 1) a baseline single-task condition, 2) listening to e-mail/text messages read by a “natural” pre-recorded human voice, 3) listening to e-mail/text messages read by a “synthetic” computerized text-to-speech system, 4) listening and composing replies to e-mail/text messages read by a “natural” voice, and 5) listening and composing replies to e-mail/text messages read by a “synthetic” voice. Each task allowed the driver to keep their eyes on the road and their hands on the steering wheel, thus any impairment to driving was caused by the diversion of non-visual attention away from the task of operating the motor vehicle.

The Residual Costs of Multitasking: Causing Trouble down the Road

Objective: The cognitive workload of three Smartphone Digital Assistants (SDA) was manipulated in an on-off manner while participants drove an instrumented vehicle in order to measure the costs associated with intermittent dual tasking. Background: Previous research has shown costs in productivity when switching between two discrete tasks; however, similar costs have not yet been examined using intermittent, continuous dual tasks. Methods: Participating drivers completed 5 conditions: baseline driving, 3 SDA conditions, and a cognitively demanding math-memory operation span (OSPAN) task, each while responding to Detection Response Task (DRT) stimuli. Within the SDA conditions, on- and off-task DRT performance was compared to baseline driving and to the OSPAN task performance. Results: The on-task periods of the SDA conditions resulted in similar RTs as the OSPAN condition, while the off-task periods did not immediately return to baseline driving performance. Post hoc analyses of the on-off transitions within the SDA conditions revealed a gradual return to baseline driving performance over the course of 18 seconds. Conclusions: The delays in returning to baseline driving performance after completing a secondary task raise concerns about the usage of in-vehicle devices while driving as the effects of the delays last beyond the cessation of the SDA interaction.