[Transient reading disorders associated with interictal epileptiform paroxysmal discharges in invasive...

Epilepsy in pediatric age are frequently associated with cognitive disorders. Different studies correlated the presence of transient cognitive disorders with the presence of interictal epileptiform discharges (IEDs).

A 23-year-old woman with pharmacoresistant focal epilepsy was evaluated with invasive videoEEG in the context of epilepsy surgery. There were selected 300 periods of 10 seconds duration from the invasive videoEEG, which were classified into two groups. Group 1 showed IEDs restricted to the cortex of the middle frontal gyrus, inferior temporal gyrus, left lateral and medial occipitotemporal gyrus (dominant hemisphere). In group 2, IEDs was observed in the upper and middle frontal gyrus, precentral, the inferior and middle temporal left gyrus. The patient read the same text during the selected peirods. The number of words read in each period was counted. The working memory was evaluated by the inverse digit test. In group 1, the average number of words read was 10.2 (95% CI: 10.04-10.35); in group 2 it was 2.3 (95% CI: 2.12-2.27; t(146) = 94.55; p < 0.0001). In group 1, the average of inverse digits was 4.05 (95% CI: 3.81-4.30); in group 2 it was 2.67 (95% CI: 2.48-2.86; t(33) = 10.34; p < 0.0001).

Our finding allows us to infer that the interference of IEDs in the cortex of the upper and middle frontal gyrus, precentral, middle and lower temporal gyrus of the dominant hemisphere, causes a dysfunction of neural networks involved in reading.