Cerebral Dysplasias: Reviewed from a Neurophysiological Perspective

Improvements in neuroimaging techniques have highlighted the role of cerebral dysplasia in developmental disorders and in epilepsy. The current classification is founded on the presumed timing of the first insult as deduced from the imaging appearances. Although clinical neurophysiological findings are often non-specific, several unusual patterns have been reported in association with certain types of malformation. These include the high amplitude rhythmic activities of lissencephaly, and focal rhythmic spikes. In this general review, we describe the electroence-phalographic and evoked potential findings in a wide range of cerebral dysplasias, including our personal experience of rare conditions such as Ramer-Lin syndrome. We focus on their role in assessment and on potential insights into pathophysiology.