Age-accelerated psychomotor slowing in temporal lobe epilepsy

Cognitive and psychomotor slowing is a complication of epilepsy and is less often a focus of investigation relative to other cognitive domains (e.g., memory). A diversity of tasks has been used to examine psychomotor slowing in epilepsy, but it remains unknown whether the degree of epilepsy-related slowing is fixed or is exacerbated with increasing task demand. Also unknown is to what degree age related slowing is accelerated in epilepsy. Participants with temporal lobe epilepsy (n=50) were compared to healthy controls (n=69) across three tasks of psychomotor speed with varied complexity. Performance was examined as a function of group (epilepsy, controls), task complexity (simple, intermediate, complex), and chronological age. The results showed that speed of performance declined across the epilepsy and control participants as a function of task complexity. Epilepsy participants were significantly slower than controls across the three tasks, and there was a significant three-way interaction (group by task complexity by age). These results demonstrate that psychomotor slowing is related to task complexity in both epilepsy and healthy control participants, always greater in epilepsy participants, and there is a significant age acceleration of psychomotor slowing in the epilepsy group that is magnified by complex tasks.