Transitory Cognitive Disorders and Learning Impairment

The findings of the studies reviewed in this chapter show that an abnormal neural activity may be responsible for cognitive impairment even when overt clinical seizures are very rare. This abnormal neural activity, only evidenced on EEG, has not only immediate consequences on cognitive performances but also long-term effects. As they occur in childhood at a critical age for the development of most cognitive abilities and the acquisition of knowledge, they may be deleterious for further academic and psychosocial achievement. The demonstration that transitory cognitive impairments may be responsible for attention and learning problems in the so-called benign epilepsy suggests that the frequency of EEG abnormalities particularly spike-wave discharges should be taken into account as a criterion for therapeutic decision in the same way as the frequency of clinical seizures. In the same way, when an epileptic child has behavioral problems and learning difficulties that are not explained by frequent seizures or medication, the presence of TCI should be suspected. Finally, in a child with sub clinical discharges on EEG, even when the global IQ is normal, poor performances on specific subtests may be related to TCI.19