Sensorimotor variables and forced expiratory volume as correlates of speed, accuracy, and variability in reaction time performance in late adulthood

The relationship between performance on measures of sensorimotor and physio logical function and performance on measures of reaction time (RT) was inve stigated using an individual differences approach. Older participants showe d greater intra-individual variability on the RT measures. They were also s lower on measures of four choice visual RT but not on measures of three cho ice auditory RT. Sensorimotor and physiological variables explained nearly all the age differences in performance on the RT tasks and showed similar p atterns of relationships with measures of speed, accuracy, and intra-indivi dual variability. The results support a common factor interpretation of the relationships among these variables in old age.