[Quantitative effect of treatment with methylphenidate on EEG--a pilot study]

Abstract

Objective: As a presumptive side effect, a lowered seizure threshold due to medication with methylphenidate remains controversial. The pilot study at hand addresses the experimental verification of this claim. Furthermore, quantitative effects of methylphenidate treatment on EEG are measured.

Method: The EEGs of 15 patients with ADHD aged 6 to 14 years were acquisitioned. Diagnosis was made according to multi-axial diagnostic procedures and in observance of all ICD-10 criteria. In order to evaluate the electrophysiological effects of methylphenidate, the EEG-data were analysed with regard to the composition of the frequency spectrum and the occurrence of pathological EEG-alterations.

Results: The analysis of EEG data prior to and subsequent to medication with methylphenidate showed an increase of occipital alpha-activity, whereas of delta-theta-activity was reduced. Beta-activity increased in the central region and showed a trend towards a frontal increase. Neither before nor after treatment with methylphenidate could pathological potentials be detected.

Conclusion: The results support the common view in the existing literature that methylphenidate does not lower the seizure threshold. Rather its effect on electrophysiological parameters can be described as a normalisation in terms of an acceleration of the occipital rhythm.