Landau–Kleffner syndrome: a rare childhood epileptic aphasia

Landau–Kleffner Syndrome (LKS), a rare epileptic aphasia which occurs at a crucial period for the development of verbal skills, arouses interest and controversy among both clinicians and neuroscientists interested in the development of language. On the one hand, the relationship between epilepsy and aphasia and the poor outcome of epileptic aphasia compared to lesional childhood aphasia is a matter of debate among the clinicians. On the other hand, the severe verbal agnosia experienced during the active period of epilepsy allows one to examine the effect of deprivation of verbal auditory input on further language development. The chronic language impairments observed in most cases following the complete recovery from epilepsy could be either a consequence of a permanent neurophysiological dysfunction (the epileptic focus) during a crucial period of functional differentiation in the brain tissue assigned to language processing (the left superior temporal cortex), or a consequence of a lack of auditory-verbal experience.