title: Alterations in working memory networks in amnestic mild cognitive impairment.
abstract: Patients with amnestic mild cognitive impairment (aMCI) show preserved or mildly impaired working memory, despite their deficits in episodic memory. We aimed to identify performance and/or neural differences between aMCI patients and matched controls on a standard working memory fMRI task. Neuropsychological assessment demonstrated aMCI impairments in verbal and visual episodic long-term memory, with intact IQ and executive function. Participants completed a standard three-level N-back task where patients were unimpaired. Functional activations in the control group were found in expected areas, including the inferior parietal lobule and dorsolateral prefrontal cortex. Group differences were found in the insula and lingual gyrus and, in a region of interest analysis, in the hippocampus. In all cases, these were caused by an absence of task-related deactivations in the aMCI group. The results are consistent with reports of failure in task-related deacivations in aMCI and could be early indications of pathology.
authors.affiliation: a King's College London, Department of Neuroimaging , Institute of Psychiatry , London , UK.
authors.forename: E M
authors.initials: EM
authors.lastname: Migo
authors.forename: M
authors.initials: M
authors.lastname: Mitterschiffthaler
authors.forename: O
authors.initials: O
authors.lastname: O'Daly
authors.forename: G R
authors.initials: GR
authors.lastname: Dawson
authors.forename: C T
authors.initials: CT
authors.lastname: Dourish
authors.forename: K J
authors.initials: KJ
authors.lastname: Craig
authors.forename: A
authors.initials: A
authors.lastname: Simmons
authors.forename: G K
authors.initials: GK
authors.lastname: Wilcock
authors.forename: E
authors.initials: E
authors.lastname: McCulloch
authors.forename: S H D
authors.initials: SH
authors.lastname: Jackson
authors.forename: M D
authors.initials: MD
authors.lastname: Kopelman
authors.forename: S C R
authors.initials: SC
authors.lastname: Williams
authors.forename: R G
authors.initials: RG
authors.lastname: Morris
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000473:pathology*; D001931:Brain Mapping; D060825:Cognitive Dysfunction / Q000150:complications* / Q000473:pathology*; D056344:Executive Function; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D008570:Memory, Short-Term / Q000502:physiology*; D008875:Middle Aged; D009434:Neural Pathways / Q000098:blood supply / Q000473:pathology; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011597:Psychomotor Performance; D011930:Reaction Time
chemical_list: D010100:Oxygen
keywords: N-back; fMRI; mild cognitive impairment; working memory