Effortful processing in the speed-accuracy tradeoff phenomenon
Forty students participated in a dual-task speed-accuracy trade-off experiment. The primary task required them to compare the relative sizes of two symbolic stimuli, and the secondary task required them to periodically identify a tone which sounded at the beginning of each trial. The primary task was performed under both speed-emphasized and accuracy-emphasized conditions. Measures of response time and proportion correct were taken for both tasks under both conditions. Results for the primary task suggested that participants adhered to the instructional emphases of speed and accuracy. Decremented performance in the secondary task was not evident with respect to proportion correct; however, secondary task response times in the speed-emphasized condition were slower than in the accuracy-emphasized condition. These data provide some evidence that speeded responding might indeed be an inherently effortful process and, hence, might not simply involve passive adjustments to response criteria.