Stroke and neurodegeneration induce different connectivity aberrations in the insula

INDIRA GARCÍA-CORDERO; LUCAS SEDEÑO; DANIEL FRAIMAN; LAURA ALETHIA DE LA FUENTE; PAULA SALAMONE; CECILIA SERRANO; LUCIANO SPOSATO; FACUNDO MANES; AGUSTIN IBAÑEZ

STROKE

LIPPINCOTT WILLIAMS & WILKINS

Lugar: Philadelphia; Año: 2015

0039-2499

Background and Purpose: Stroke and neurodegeneration cause significant braindamage and cognitive impairment, especially if the insular cortex (InsC) iscompromised. This study explores for the first time whether these two etiologiesdifferentially alter connectivity patterns in the InsC.Methods: Resting state-FMRI data were collected from insular stroke patients,behavioral variant frontotemporal dementia (bvFTD) patients, and healthy controls.Data from the three groups were assessed through a correlation function analysis.Specifically, we compared decreases in connectivity as a function of voxel Euclideandistance within the InsC.Results: Relative to controls, stroke patients showed faster connectivity decays as afunction of distance (hypoconnectivity). In contrast, the bvFTD group exhibitedsignificant hyperconnectivity between neighboring voxels. Both patient groups evincedglobal hypoconnectivity. No between-group differences were observed in avolumetrically and functionally comparable region without ischemia orneurodegeneration.Conclusions: Functional InsC connectivity is affected differently by cerebral ischemiaand neurodegeneration, possibly due to differences in the etiology-specificpathophysiological mechanisms of each disease. These findings have important clinicaland theoretical implications.