Age-related decline in Digit-Symbol performance: eye-movement and video analysis

Examines age-related decline in Digit-Symbol performance using variables obtained from a slow-motion analysis of a first person perspective video filmed during test completion, including superimposed cross-hairs indicating eye movements. Standard WAIS-3 DSCT scores and the video-derived variables were compared across two age groups (mean age 20 years vs. mean age 59 years). The older group performed more poorly overall, t(16)=-2.359, p=.031. The correlation between writing time per item and overall performance was (negatively) larger in the older group compared with the younger group, z=-2.180, p=.014. There was no difference between the groups' correlation coefficients with respect to key search latency and overall performance, z=-0.064, p=.525. Overall these results suggest that characterisation of the age-related slowing on Digit-Symbol tests as a psychomotor deficit is appropriate.