Mechanisms of Age-Dependent Increase of Perisylvian Cortical Excitability

An age-dependent increase of perisylvian cortical excitability is the widely accepted mechanism behind rolandic epilepsy. Its EEG correlate, the rolandic sharp wave focus, however, is observed also in 2.5% of healthy children. Its incidence is increased in children with cognitive developmental deficits or some brain lesions. In all cases, this EEG activity disappears during further brain development in early adolescence. This suggests a clear relationship to brain maturation.

In lack of an adequate animal model, there are very limited ways for experimental research. As there is no single known gene behind this phenomenon, we do not have any clues for molecular explanations or modeling. This presentation therefore will mainly rely on clinical observations. The following questions will be discussed:

• Is there a correlation between the occurrence of perisylvian sharp waves and other neurodevelopmental parameters?

• Is there a relationship between the disappearance of these foci and other neurodevelopmental parameters?

• Which known biological-neurodevelopmental processes occur at the typical ages of appearance and disappearance of perisylvian sharp waves?