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 physiological function and performance on measures of reaction time (RT) was investigated using an individual differences approach. Older participants showed greater intra-individual variability on the RT measures. They were also slower on measures of four choice visual RT but not on measures of three choice auditory RT. Sensorimotor and physiological variables explained nearly all the age differences in performance on the RT tasks and showed similar patterns of relationships with measures of speed, accuracy, and intra-individual variability. The results support a common factor interpretation of the relationships among these variables in old age.