title: Intrahemispheric Perfusion in Chronic Stroke-Induced Aphasia.
abstract: Stroke-induced alterations in cerebral blood flow (perfusion) may contribute to functional language impairments and recovery in chronic aphasia. Using MRI, we examined perfusion in the right and left hemispheres of 35 aphasic and 16 healthy control participants. Across 76 regions (38 per hemisphere), no significant between-subjects differences were found in the left, whereas blood flow in the right was increased in the aphasic compared to the control participants. Region-of-interest (ROI) analyses showed a varied pattern of hypo- and hyperperfused regions across hemispheres in the aphasic participants; however, there were no significant correlations between perfusion values and language abilities in these regions. These patterns may reflect autoregulatory changes in blood flow following stroke and/or increases in general cognitive effort, rather than maladaptive language processing. We also examined blood flow in perilesional tissue, finding the greatest hypoperfusion close to the lesion (within 0-6 mm), with greater hypoperfusion in this region compared to more distal regions. In addition, hypoperfusion in this region was significantly correlated with language impairment. These findings underscore the need to consider cerebral perfusion as a factor contributing to language deficits in chronic aphasia as well as recovery of language function.
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Communication Sciences and Disorders, School of Communication, Northwestern University, Evanston, IL, USA; Department of Neurology, Feinberg School of Medicine, Northwestern University, Evanston, IL, USA.
authors.forename: Cynthia K
authors.identifier: 0000-0003-3197-3457
authors.initials: CK
authors.lastname: Thompson
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Communication Sciences and Disorders, School of Communication, Northwestern University, Evanston, IL, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Walenski
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Radiology, Feinberg School of Medicine, Northwestern University, Evanston, IL, USA.
authors.forename: YuFen
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Massachusetts General Hospital, Department of Neurology, Harvard Medical School, Boston, MA, USA.
authors.forename: David
authors.initials: D
authors.lastname: Caplan
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Speech, Language, and Hearing, College of Health & Rehabilitation, Boston University, Boston, MA, USA.
authors.forename: Swathi
authors.identifier: 0000-0003-1586-8913
authors.initials: S
authors.lastname: Kiran
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Cognitive Science, Krieger School of Arts & Sciences, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Brenda
authors.initials: B
authors.lastname: Rapp
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Psychology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL, USA.
authors.forename: Kristin
authors.initials: K
authors.lastname: Grunewald
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Psychology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL, USA.
authors.forename: Mia
authors.initials: M
authors.lastname: Nunez
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Psychology, Weinberg College of Arts and Sciences, Northwestern University, Evanston, IL, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Zinbarg
authors.affiliation: Center for the Neurobiology of Language Recovery, Northwestern University, Evanston, IL, USA; Department of Radiology, Feinberg School of Medicine, Northwestern University, Evanston, IL, USA.
authors.forename: Todd B
authors.initials: TB
authors.lastname: Parrish
mesh_terms: D000328:Adult; D000368:Aged; D001037:Aphasia / Q000000981:diagnostic imaging* / Q000209:etiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D054022:Cerebrum / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000502:physiology*; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D020521:Stroke / Q000150:complications / Q000000981:diagnostic imaging*