The effects of aging and cognitive performance on patterns of neural activity measured by functional magnetic resonance imaging

Persistent Link:
http://hdl.handle.net/10150/280555
Title:
The effects of aging and cognitive performance on patterns of neural activity measured by functional magnetic resonance imaging
Author:
Johnson, Jennifer Lee
Issue Date:
2004
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Previous functional magnetic resonance imaging (fMRI) research has shown that older adults activated bilateral frontal regions during tasks in which young adults had unilateral frontal activation (Cabeza, 2001). It has been suggested that older adults recruit bilateral frontal regions to compensate for declining brain function in other regions (Cabeza, Anderson, Locantore, and McIntosh, 2002). The primary aim of the current study was to determine how bilateral activation patterns observed in the frontal lobe during encoding and recognition were related to both cognitive performance of older adults and to function in other brain regions. Thirty-five older adults and 9 young adults completed an encoding and recognition task during fMRI scanning. During the encoding scans participants determined whether presented words were "natural" or "man made" objects. During the recognition scans, participants made "old/new" judgments for each word presented. Four sets of bilateral regions of interest (ROI) were defined from an overlap image of all participants' fMRI data: (1) right and left frontal cortex, (2) right and left medial temporal lobe, (3) right and left parietal lobe, and (4) right and left lateral temporal lobe. On a separate day participants completed a neuropsychological testing session that included a series of tests that had been previously used to characterize older adults in two cognitive domains, frontal (FL) and medial temporal lobe (MTL) function (Glisky, Polster & Routhieaux, 1995; Glisky, Rubin & Davidson, 2001). Consistent with the previous research, older adults showed greater bilateral fMRI activation in the frontal lobes during encoding than young adults. However, bilateral activation in the frontal lobes during encoding was associated with two different activation patterns: (1) when MTL activation was present, bilateral frontal activation was observed in older adults with high FL factor scores; (2) when the MTL was not active, bilateral frontal activation was found in older adults with low MTL factor scores. Older adults with high FL factor scores but who did not activate MTL had left lateralized frontal activation. Importantly, older adults with and without MTL activation did not differ in recognition performance scores, or factor scores.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Biology, Neuroscience.; Psychology, Psychobiology.; Psychology, Cognitive.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Psychology
Degree Grantor:
University of Arizona
Advisor:
Ryan, Lee

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleThe effects of aging and cognitive performance on patterns of neural activity measured by functional magnetic resonance imagingen_US
dc.creatorJohnson, Jennifer Leeen_US
dc.contributor.authorJohnson, Jennifer Leeen_US
dc.date.issued2004en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPrevious functional magnetic resonance imaging (fMRI) research has shown that older adults activated bilateral frontal regions during tasks in which young adults had unilateral frontal activation (Cabeza, 2001). It has been suggested that older adults recruit bilateral frontal regions to compensate for declining brain function in other regions (Cabeza, Anderson, Locantore, and McIntosh, 2002). The primary aim of the current study was to determine how bilateral activation patterns observed in the frontal lobe during encoding and recognition were related to both cognitive performance of older adults and to function in other brain regions. Thirty-five older adults and 9 young adults completed an encoding and recognition task during fMRI scanning. During the encoding scans participants determined whether presented words were "natural" or "man made" objects. During the recognition scans, participants made "old/new" judgments for each word presented. Four sets of bilateral regions of interest (ROI) were defined from an overlap image of all participants' fMRI data: (1) right and left frontal cortex, (2) right and left medial temporal lobe, (3) right and left parietal lobe, and (4) right and left lateral temporal lobe. On a separate day participants completed a neuropsychological testing session that included a series of tests that had been previously used to characterize older adults in two cognitive domains, frontal (FL) and medial temporal lobe (MTL) function (Glisky, Polster & Routhieaux, 1995; Glisky, Rubin & Davidson, 2001). Consistent with the previous research, older adults showed greater bilateral fMRI activation in the frontal lobes during encoding than young adults. However, bilateral activation in the frontal lobes during encoding was associated with two different activation patterns: (1) when MTL activation was present, bilateral frontal activation was observed in older adults with high FL factor scores; (2) when the MTL was not active, bilateral frontal activation was found in older adults with low MTL factor scores. Older adults with high FL factor scores but who did not activate MTL had left lateralized frontal activation. Importantly, older adults with and without MTL activation did not differ in recognition performance scores, or factor scores.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectBiology, Neuroscience.en_US
dc.subjectPsychology, Psychobiology.en_US
dc.subjectPsychology, Cognitive.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplinePsychologyen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRyan, Leeen_US
dc.identifier.proquest3132233en_US
dc.identifier.bibrecord.b46708972en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.