Computational support, not primacy, distinguishes compensatory memory reorganization in epilepsy

• DOI: 10.1093/braincomms/fcab025
• Publication Date: 2021-03-05T20:21:11Z
• Authors: Joseph I Tracy; Kapil Chaudhary; Shilpi Modi; Andrew Crow; Ashith Kumar; David Weinstein; Michael R Sperling
• Keywords: 0301 basic medicine; 03 medical and health sciences; 0302 clinical medicine; Original Article; 3. Good health

Temporal lobe epilepsy is associated with impairment in episodic memory. A substantial subgroup, however, able to maintain adequate memory despite temporal pathology. Missing from prior work cognitive reorganization a direct comparison of patients intact status those who are impaired. Little known about the regional activations, functional connectivities and/or network reconfigurations that implement changes primary computations or support functions drive adaptive plasticity and compensated We utilized task MRI on 54 unilateral 24 matched healthy controls during performance paired-associate address three questions: (i) which regions epilepsy, do they vary as function good versus poor performance, (ii) there unique connectivity present encoding accounts for by preservation supportive allow responses (iii) what features most distinctive: it magnitude location presence enhanced connections key structures such hippocampus? The study revealed non-dominant hemisphere (right posterior regions) involving both increased activity modulatory communication hippocampi important left compared impaired status. profile involved areas neither contralateral homologues areas, nor traditionally considered computationally None these activation were advantaged controls. Our emphasis different levels yielded insight into two forms reorganization: computational primacy, where showed little change relative controls, abnormalities. analyses isolated activations mediating implements truly compensatory epilepsy. results provided new perspective deficits making clear arise not just knockout hub, but failure instantiate complex set responses. Such ensure successful demonstrated keeping track levels, we can increase understanding brain neuroplasticity