Stroke and Neurodegeneration Induce Different Connectivity Aberrations in the Insula

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

STROKE

LIPPINCOTT WILLIAMS & WILKINS

Lugar: Philadelphia; Año: 2015

0039-2499

Background and Purpose?Stroke and neurodegeneration cause significant brain damage and cognitive impairment,especially if the insular cortex is compromised. This study explores for the first time whether these 2 causes differentiallyalter connectivity patterns in the insular cortex.Methods?Resting state?functional magnetic resonance imaging data were collected from patients with insular stroke,patients with behavioral variant frontotemporal dementia, and healthy controls. Data from the 3 groups were assessedthrough a correlation function analysis. Specifically, we compared decreases in connectivity as a function of voxelEuclidean distance within the insular cortex.Results?Relative to controls, patients with stroke showed faster connectivity decays as a function of distance(hypoconnectivity). In contrast, the behavioral variant frontotemporal dementia group exhibited significanthyperconnectivity between neighboring voxels. Both patient groups evinced global hypoconnectivity. No between-groupdifferences were observed in a volumetrically and functionally comparable region without ischemia or neurodegeneration.Conclusions?Functional insular cortex connectivity is affected differently by cerebral ischemia and neurodegeneration,possibly because of differences in the cause-specific pathophysiological mechanisms of each disease. These findings haveimportant clinical and theoretical implications.