The Tactile Detection Response Task: Preliminary Validation for Measuring the Attentional Effects of Cognitive Load

Improved measures of the attentional effects of cognitive load are needed to reduce potential crashes caused by secondary tasks performed while driving. The Tactile Detection Response Task (TDRT) in the proposed ISO Draft Standard WD17488 was tested in laboratory and on-road venues with 16 and 15 subjects, respectively. A sensitivity test used a purely cognitive load increase from an easy (0- back) to hard (1-back) auditory-vocal task. The TDRT response time increased by 90±21 msec in the laboratory, and by 135±34 msec on the road, while the miss rate increased by 4% in the laboratory and 5% on the road, thus validating TDRT sensitivity to an increase in purely cognitive load. A specificity test used a visual load increase with little cognitive load difference from an easy to hard visual-manual “Surrogate Reference Task” (SuRT), to which the TDRT should not respond. The TDRT response time and miss rate to the SuRT did not increase in the laboratory or road as a result of the increased visual load, providing preliminary validation that the TDRT may be both specific and sensitive to the attentional effects of cognitive load.