Auditory Reaction Time in People With Epilepsy and Healthy Controls

Simple reaction time (SRT) to acoustic stimuli is a typical parameter used in the assessment of driving ability in people with epilepsy (PWE). In clinical practice, auditory SRT is commonly compared during and outside of epileptiform discharges (ED). Yet, a subset of PWE also has slowed SRT outside their ED, possibly because of antiseizure medication (ASM) or disease-associated network alterations. SRT values should therefore be compared with reference values from matched controls which are currently lacking in practice. We here aimed to find a reference range of SRT in healthy controls using the same paradigm as commonly used in PWE.

We measured auditory SRT in heathy control subjects without epilepsy and a cohort of patients with epilepsy. We matched the control cohort, according to age and sex, to a cohort of PWE who had previously been recorded at our center using the same task. This allowed to compare auditory SRT between a control cohort and a cohort of PWE.

The control group showed a significantly lower mean SRT latency and a smaller SRT variability as compared with PWE. Within the cohort of PWE, the SRT was significantly prolonged during periods with ED. Potential confounding factors, such as age, did not show any significant contribution to auditory SRT.

Our findings demonstrate a small intrapersonal variance of SRT in the control group. Therefore, outlier SRT values in PWE during ED are likely a useful parameter for assessing driving ability.