An Initial Assessment of the Significance of Task Pacing on Self-Report and Physiological Measures of Workload While Driving

Abstract

Summary:In block A of a simulator study, a sample of 38 drivers showed a stepwise increase in heart rate and skin conductance level (SCL) from single task driving and across 3 levels of an auditory presentation -verbal response dual task (n-back), replicating findings from on-road research. Subjective ratings showed a similar stepwise increase, establishing concurrent validity of the physiological indices as measures of workload. In block B, varying the inter-stimulus interval in the intermediate 1-back level of the task resulted in a pattern across self-report workload ratings, heart rate, and SCL suggesting that task pacing may influence effective workload. Further consideration of the impact of task pacing in auditoryverbal in-vehicle applications is indicated.

How does eco-driving make us feel? Considering the psychological effects of eco-driving

“…to have high levels of concurrent validity with physiological measures including both heart rate and skin conductance levels when specifically exploring the driving task (Mehler & Reimer, 2013). That said greater understanding of the physiological effects of engaging with eco-driving practices would support the view that engaging with eco-driving behaviours directly impacts the drivers state.…”

Effects of an 'Expert Mode' Voice Command System on Task Performance, Glance Behavior & Driver Physiology

“…Finally, participants were asked to perform four levels of a delayed digit recall n-back task, e.g. blank back, 0-back, 1-back and 2-back [8,9] the results of which are not addressed in this paper.…”

The MIT AgeLab n-back

“…The cognitive load placed on drivers from the three levels of the n-back task results in a linear increase in heart rate (see Figure 1) and a similar pattern in skin conductance [8,10]. More complex effects appear in driving performance measures and drivers' allocation of attention; an increase in gaze centralization appears up to the 1-back level and a nominal increase (potentially indicating a plateau effect) appears at the 2-back level [16].…”

“…The same task has been used consistently starting in the AgeLab simulator experiment [11], a pilot on-road study in 2007 [14,15,18], methodological studies in the simulator [8,28] and the field [27,29], a large onroad study in 2008 [10,16], in projects utilizing the task to produce reference levels of cognitive workload [12,17,20], drivers' responses to cognitive demands [3,19] and efforts to develop physiological based methods for driver state estimation [22,25]. Additional background, details on the structure and methodological implementation of the task, and participant training materials can be found in [9].…”

“…Recent efforts [8,12] have also included a "blank-back" condition where participants simply listen to a series of single digit numbers (like the other n-back levels) but in which participants do not have to hold in the number in memory or repeat it out loud.…”