title: Aβ-related hyperactivation in frontoparietal control regions in cognitively normal elderly.
abstract: The accumulation of amyloid-beta (Aβ) peptides, a pathologic hallmark of Alzheimer's disease, has been associated with functional alterations in cognitively normal elderly, most often in the context of episodic memory with a particular emphasis on the medial temporal lobes. The topography of Aβ deposition, however, highly overlaps with frontoparietal control (FPC) regions implicated in cognitive control/working memory. To examine Aβ-related functional alternations in the FPC regions during a working memory task, we imaged 42 young and 57 cognitively normal elderly using functional magnetic resonance imaging during a letter Sternberg task with varying load. Based on (18)F-florbetaben-positron emission tomography scan, we determined older subjects' amyloid positivity (Aβ+) status. Within brain regions commonly recruited by all subject groups during the delay period, age and Aβ deposition were independently associated with load-dependent frontoparietal hyperactivation, whereas additional compensatory Aβ-related hyperactivity was found beyond the FPC regions. The present results suggest that Aβ-related hyperactivation is not specific to the episodic memory system but occurs in the PFC regions as well.
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA. Electronic address: hwamee.oh@columbia.edu.
authors.forename: Hwamee
authors.initials: H
authors.lastname: Oh
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Steffener
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Qolamreza R
authors.initials: QR
authors.lastname: Razlighi
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Habeck
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Liu
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Yunglin
authors.initials: Y
authors.lastname: Gazes
authors.affiliation: Division of Aging and Dementia, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Janicki
authors.affiliation: Cognitive Neuroscience Division, Department of Neurology, Columbia University College of Physicians and Surgeons, New York, NY, USA.
authors.forename: Yaakov
authors.initials: Y
authors.lastname: Stern
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism* / Q000473:pathology*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D003071:Cognition / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010296:Parietal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D049268:Positron-Emission Tomography; D055815:Young Adult
chemical_list: D016229:Amyloid beta-Peptides
keywords: Aging; Amyloid PET; Amyloid-beta deposition; Frontoparietal control regions; Working memory; fMRI