Myoclonic seizures induced by writing, calculation with figures and constructive acts - with special reference to 'neuropsychological EEG activation'

Only 11 cases of so-called graphogenic epilepsy and allied types of epilepsy in which seizures are induced mostly by writing have ever been reported. We experienced a case (27-yr-old, left-handed man) in which paroxysmal discharges and/or seizures were elicited not only by writing but also by calculation with figures or by constructive acts. On general EEG examination, no particular findings could be obtained. On 'neuropsychological EEG activation' (NPA), however, paroxysmal discharges and myoclonic seizures of hands were clearly induced by writing, calculation with figures and constructive acts. Measuring the amplitude of each preceding spike of the activated focal, bilateral or generalized spike and wave discharges, the following was found: the highest amplitude of the spikes tended to be seen over the right central area with writing, over the right frontal area with calculation with figures, and over the left parietal-central areas with constructive acts. An application of NPA for the diagnosis of graphogenic epilepsy was discussed. Characteristics and mechanism of the activated paroxysmal discharges by use of NPA and criteria in diagnosing graphogenic epilepsy were discussed as well. It was guessed that detailed examination of so-called graphogenic epilepsy and allied types of epilepsy may contribute to the elucidation of higher cognitive functions, such as writing, calculation with figures and constructive acts in relation to handedness.