The relationship of medial temporal lobe epilepsy with the declarative memory system


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Journal of Epileptology

Foundation of Epileptology

Subject: Medicine


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VOLUME 24 , ISSUE 2 (December 2016) > List of articles

The relationship of medial temporal lobe epilepsy with the declarative memory system

Péter Halász *

Keywords : Medial temporal lobe epilepsy, memory consolidation, hippocampal memory, slow wave sleep sharp wave ripple, sleep spiking effect

Citation Information : Journal of Epileptology. Volume 24, Issue 2, Pages 157-165, DOI:

License : (CC BY 4.0)

Received Date : 03-October-2016 / Accepted: 10-November-2016 / Published Online: 22-November-2016



Introduction. Medial temporal lobe of epilepsy (MTLE) is considered as local/regional epilepsy. However, as was discussed in Part I of this review (Halasz, 2016a) there is more evidence regarding the involvement of both temporal lobes so as to consider MTLE as one of the typical bilateral system epilepsies.

Aim. To provide contemporary review of MTLE in relation to the declarative memory system and the newly recognized hippocampo-frontal memory consolidation during slow wave sleep.

Methods. A review of the available literature on experimental and clinical data and also the authors own studies in MTLE patients.

Review, discussion and results. New experimental and clinical neurophysiological data have shown that MTLE is closely linked to the hippocampal memory system. It is likely that hippocampal spiking is the epileptic variations of the normal sharp wave ripple events mediating the encoding and consolidation of memory engrams by a hippocampo-frontal dialogue during slow wave sleep.

Conclusions. The source of memory impairment in MTLE patients is not merely the cell loss and synaptic transformation of the hippocampal structure, but the every night interference with memory consolidation due to interictal spiking.

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