Neural substrates of word generation during stroke recovery

The influence of cortical hypoperfusion

V. Prabhakaran, S. P. Raman, M. R. Grunwald, A. Mahadevia, N. Hussain, Hanzhang Lu, Peter C Van Zijl, Argye Hillis-Trupe

Research output: Contribution to journalArticle

Abstract

Several studies have demonstrated reorganization of cognitive and motor function caused by stroke. This study examined the influence of hypoperfused brain regions, in addition to the area of the infarct itself, on reorganization of the cognitive processes underlying word generation in stroke patients. In addition, we also sought to determine the influence of hypoperfusion on the blood oxygen level dependent/(BOLD) effect. Subjects with left and right subacute or chronic subcortical strokes, along with normal controls, were imaged while performing a verbal fluency task (word generation). The study population included six normal subject and six stroke patients with subcortical infarcts and cortical hypoperfusion in the middle cerebral artery territory who had recovered or improved markedly in word fluency. While normal subjects displayed a left-lateralized fronto-temporo-parietal and bilateral cingulo-striatal- thalamic-cerebellar network, the activation pattern of stroke patients was determined both by the hypoperfused regions and infarcted areas of the brain. Specifically, patients showed diminished BOLD effect in the cortical regions that were hypoperfused, even though their infarcts were subcortical, and showed increased BOLD effect in the homologous regions of the normal hemisphere. This finding raises the possibility that cortical hypoperfusion in the absence of infarct can cause shift of language functions to the opposite, intact hemisphere. However, reduced BOLD effect in the task relative to rest was found in hypoperfused regions in two patients, raising the possibility that regional function persisted, even though vascular reactivity was impaired. Results illustrate the complexities of functional imaging studies of recovery in patients with vascular lesions.

Original languageEnglish (US)
Pages (from-to)45-52
Number of pages8
JournalBehavioural Neurology
Volume18
Issue number1
StatePublished - 2007

Fingerprint

Stroke
Oxygen
Blood Vessels
Corpus Striatum
Middle Cerebral Artery
Brain
Cognition
Language
Population

ASJC Scopus subject areas

  • Neuropsychology and Physiological Psychology
  • Neuroscience(all)

Cite this

Prabhakaran, V., Raman, S. P., Grunwald, M. R., Mahadevia, A., Hussain, N., Lu, H., ... Hillis-Trupe, A. (2007). Neural substrates of word generation during stroke recovery: The influence of cortical hypoperfusion. Behavioural Neurology, 18(1), 45-52.

Neural substrates of word generation during stroke recovery : The influence of cortical hypoperfusion. / Prabhakaran, V.; Raman, S. P.; Grunwald, M. R.; Mahadevia, A.; Hussain, N.; Lu, Hanzhang; Van Zijl, Peter C; Hillis-Trupe, Argye.

In: Behavioural Neurology, Vol. 18, No. 1, 2007, p. 45-52.

Research output: Contribution to journalArticle

Prabhakaran V, Raman SP, Grunwald MR, Mahadevia A, Hussain N, Lu H et al. Neural substrates of word generation during stroke recovery: The influence of cortical hypoperfusion. Behavioural Neurology. 2007;18(1):45-52.
Prabhakaran, V. ; Raman, S. P. ; Grunwald, M. R. ; Mahadevia, A. ; Hussain, N. ; Lu, Hanzhang ; Van Zijl, Peter C ; Hillis-Trupe, Argye. / Neural substrates of word generation during stroke recovery : The influence of cortical hypoperfusion. In: Behavioural Neurology. 2007 ; Vol. 18, No. 1. pp. 45-52.
@article{ee0ed7bc81dc4f3592548ccc4c2b3cba,
title = "Neural substrates of word generation during stroke recovery: The influence of cortical hypoperfusion",
abstract = "Several studies have demonstrated reorganization of cognitive and motor function caused by stroke. This study examined the influence of hypoperfused brain regions, in addition to the area of the infarct itself, on reorganization of the cognitive processes underlying word generation in stroke patients. In addition, we also sought to determine the influence of hypoperfusion on the blood oxygen level dependent/(BOLD) effect. Subjects with left and right subacute or chronic subcortical strokes, along with normal controls, were imaged while performing a verbal fluency task (word generation). The study population included six normal subject and six stroke patients with subcortical infarcts and cortical hypoperfusion in the middle cerebral artery territory who had recovered or improved markedly in word fluency. While normal subjects displayed a left-lateralized fronto-temporo-parietal and bilateral cingulo-striatal- thalamic-cerebellar network, the activation pattern of stroke patients was determined both by the hypoperfused regions and infarcted areas of the brain. Specifically, patients showed diminished BOLD effect in the cortical regions that were hypoperfused, even though their infarcts were subcortical, and showed increased BOLD effect in the homologous regions of the normal hemisphere. This finding raises the possibility that cortical hypoperfusion in the absence of infarct can cause shift of language functions to the opposite, intact hemisphere. However, reduced BOLD effect in the task relative to rest was found in hypoperfused regions in two patients, raising the possibility that regional function persisted, even though vascular reactivity was impaired. Results illustrate the complexities of functional imaging studies of recovery in patients with vascular lesions.",
author = "V. Prabhakaran and Raman, {S. P.} and Grunwald, {M. R.} and A. Mahadevia and N. Hussain and Hanzhang Lu and {Van Zijl}, {Peter C} and Argye Hillis-Trupe",
year = "2007",
language = "English (US)",
volume = "18",
pages = "45--52",
journal = "Behavioural Neurology",
issn = "0953-4180",
publisher = "IOS Press",
number = "1",

}

TY - JOUR

T1 - Neural substrates of word generation during stroke recovery

T2 - The influence of cortical hypoperfusion

AU - Prabhakaran, V.

AU - Raman, S. P.

AU - Grunwald, M. R.

AU - Mahadevia, A.

AU - Hussain, N.

AU - Lu, Hanzhang

AU - Van Zijl, Peter C

AU - Hillis-Trupe, Argye

PY - 2007

Y1 - 2007

N2 - Several studies have demonstrated reorganization of cognitive and motor function caused by stroke. This study examined the influence of hypoperfused brain regions, in addition to the area of the infarct itself, on reorganization of the cognitive processes underlying word generation in stroke patients. In addition, we also sought to determine the influence of hypoperfusion on the blood oxygen level dependent/(BOLD) effect. Subjects with left and right subacute or chronic subcortical strokes, along with normal controls, were imaged while performing a verbal fluency task (word generation). The study population included six normal subject and six stroke patients with subcortical infarcts and cortical hypoperfusion in the middle cerebral artery territory who had recovered or improved markedly in word fluency. While normal subjects displayed a left-lateralized fronto-temporo-parietal and bilateral cingulo-striatal- thalamic-cerebellar network, the activation pattern of stroke patients was determined both by the hypoperfused regions and infarcted areas of the brain. Specifically, patients showed diminished BOLD effect in the cortical regions that were hypoperfused, even though their infarcts were subcortical, and showed increased BOLD effect in the homologous regions of the normal hemisphere. This finding raises the possibility that cortical hypoperfusion in the absence of infarct can cause shift of language functions to the opposite, intact hemisphere. However, reduced BOLD effect in the task relative to rest was found in hypoperfused regions in two patients, raising the possibility that regional function persisted, even though vascular reactivity was impaired. Results illustrate the complexities of functional imaging studies of recovery in patients with vascular lesions.

AB - Several studies have demonstrated reorganization of cognitive and motor function caused by stroke. This study examined the influence of hypoperfused brain regions, in addition to the area of the infarct itself, on reorganization of the cognitive processes underlying word generation in stroke patients. In addition, we also sought to determine the influence of hypoperfusion on the blood oxygen level dependent/(BOLD) effect. Subjects with left and right subacute or chronic subcortical strokes, along with normal controls, were imaged while performing a verbal fluency task (word generation). The study population included six normal subject and six stroke patients with subcortical infarcts and cortical hypoperfusion in the middle cerebral artery territory who had recovered or improved markedly in word fluency. While normal subjects displayed a left-lateralized fronto-temporo-parietal and bilateral cingulo-striatal- thalamic-cerebellar network, the activation pattern of stroke patients was determined both by the hypoperfused regions and infarcted areas of the brain. Specifically, patients showed diminished BOLD effect in the cortical regions that were hypoperfused, even though their infarcts were subcortical, and showed increased BOLD effect in the homologous regions of the normal hemisphere. This finding raises the possibility that cortical hypoperfusion in the absence of infarct can cause shift of language functions to the opposite, intact hemisphere. However, reduced BOLD effect in the task relative to rest was found in hypoperfused regions in two patients, raising the possibility that regional function persisted, even though vascular reactivity was impaired. Results illustrate the complexities of functional imaging studies of recovery in patients with vascular lesions.

UR - http://www.scopus.com/inward/record.url?scp=33847346908&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33847346908&partnerID=8YFLogxK

M3 - Article

VL - 18

SP - 45

EP - 52

JO - Behavioural Neurology

JF - Behavioural Neurology

SN - 0953-4180

IS - 1

ER -