Partial childhood epilepsy and reaction time: the effect of interictal EEG discharges

A study was conducted on seven children (five females and two males, aged 5.7-13.1 years) affected with partial epilepsy which was well controlled by therapy. A computer was connected on-line to a polygraph and during two EEG recordings, the subject had to react to the appearance of a colored rectangle on the display screen by pushing a key on the keyboard: these events were automatically marked on the trace of a polygraphic channel. By means of Anova analysis it was demonstrated that during the same recording, reactions simultaneous to paroxysmal discharges were not significantly slower than those measured during free intervals. However, in the same patient, reaction times were significantly prolonged during recordings characterized by a higher rate of EEG paroxysmal activity.