ABSTRACTThe present study was designed to test the hypothesis that individual differences in the speed of habituation of the phasic eleclrodermal response (EDR) reflect characteristic rates of attentional decrement with stimulus repetition. Subjects selected for the extrems of EDR habituation speed to a pure tone were subsequently tested in an auditory vigilance task. Slow habituators showed a high and substained rate of signal detection, while Fast habituatos showed a lower overall rate and a time‐on‐task decrement. Further analyses employing signal detection theory measures indicated that these detection differences were due to group differences in response criterion levels rather than to differences in the rate of attentional decrement. The implications of this finding for understanding individual differences in EDR habituation speed are discus