Mechanism of seizure-induced retrograde amnesia

Aijaz Ahmad Naik; Huayu Sun; Cedric L Williams; Daniel S Weller; J Julius Zhu; Jaideep Kapur

doi:10.1016/j.pneurobio.2020.101984

Mechanism of seizure-induced retrograde amnesia

Prog Neurobiol. 2021 May:200:101984. doi: 10.1016/j.pneurobio.2020.101984. Epub 2020 Dec 31.

Authors

Aijaz Ahmad Naik¹, Huayu Sun², Cedric L Williams³, Daniel S Weller⁴, J Julius Zhu⁵, Jaideep Kapur⁶

Affiliations

¹ Department of Neurology, University of Virginia, Charlottesville, VA, USA.
² UVA Brain Institute, University of Virginia, Charlottesville, VA, USA.
³ Department of Psychology, University of Virginia, Charlottesville, VA, USA.
⁴ Department of Electrical and Computer Engineering, University of Virginia, USA.
⁵ Department of Pharmacology, University of Virginia, Charlottesville, VA, USA.
⁶ Department of Neurology, University of Virginia, Charlottesville, VA, USA; UVA Brain Institute, University of Virginia, Charlottesville, VA, USA; Department of Neuroscience, University of Virginia, Charlottesville, VA, USA. Electronic address: jk8t@virginia.edu.

Abstract

Seizures cause retrograde amnesia, but underlying mechanisms are poorly understood. We tested whether seizure activated neuronal circuits overlap with spatial memory engram and whether seizures saturate LTP in engram cells. A seizure caused retrograde amnesia for spatial memory task. Spatial learning and a seizure caused cFos expression and synaptic plasticity overlapping set of neurons in the CA1 of the hippocampus. Recordings from learning-labeled CA1 pyramidal neurons showed potentiated synapses. Seizure-tagged neurons were also more excitable with larger rectifying excitatory postsynaptic currents than surrounding unlabeled neurons. These neurons had enlarged dendritic spines and saturated LTP. A seizure immediately after learning, reset the memory engram. Seizures cause retrograde amnesia through shared ensembles and mechanisms.

Keywords: EPSC; Engram; LTP; Seizure; T maze; TRAP.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Amnesia, Retrograde* / etiology
CA1 Region, Hippocampal
Excitatory Postsynaptic Potentials
Hippocampus
Humans
Neuronal Plasticity
Pyramidal Cells
Seizures* / complications
Synapses

Abstract

Publication types

MeSH terms

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