Landau±Klener syndrome: a rare childhood epileptic aphasia Marie-NoeÈlle Metz-Lutz a, *, Caroline Seegmuller a , Catherine Kleitz a , Anne de Saint Martin a, b , Edouard Hirsch a , Christian Marescaux a a INSERM U 398, Ho Ãpitaux Universitaires de Strasbourg, Clinique Neurologique, Strasbourg, 6709 Strasbourg Cedex, France b Service de PeÂdiatrie, Ho Ãpitaux Universitaires de Strasbourg, Strasbourg, France Abstract Landau±Klener 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 eect 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 dierentiation in the brain tissue assigned to language processing (the left superior temporal cortex), or a consequence of a lack of auditory-verbal experience. This paper reviews the clinical and experimental studies of Landau±Klener Syndrome with the aim of precisely de®ning the two main clinical features of the syndrome, the aphasic disorders and the epilepsy and examining their relationship. The recent ®ndings of a cognitive study of the components of the verbal memory system in six LKS patients who recovered from epilepsy and aphasia are presented. These data suggest the possibility of a de®cit within the phonological short-term memory system that would account for both the poor vocabulary development and the persisting impairment of verbal comprehension in the late outcome of LKS. # 1999 Elsevier Science Ltd. All rights reserved. 0911-6044/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S0911-6044(99)00013-5 Journal of Neurolinguistics 12 (1999) 167±179 www.elsevier.com/locate/jneuroling * Corresponding author. E-mail address: metzlutz@neurochem.u-strasbg.fr (M.-N. Metz-Lutz).