Temporal integration of 3D coherent motion cues defining visual objects of unknown orientation is impaired in amnestic mild cognitive impairment and Alzheimer's disease.
The nature of visual impairments in Alzheimer's disease (AD) and their relation with other cognitive deficits remains highly debated. We asked whether independent visual deficits are present in AD and amnestic forms of mild cognitive impairment (MCI) in the absence of other comorbidities by performi...
| Publicado en: | Journal of Alzheimer's Disease Vol. 28; no. 1; pp. 885 - 897 |
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| Autores principales: | , , , , , , , , , |
| Formato: | research Journal Article |
| Publicado: |
Sage Publications Inc.
2012
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| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=104520482&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 104520482 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 13872877 FLR jtl: Journal of Alzheimer's Disease issn: 13872877 maglogo: N pubinfo: dt: 2012 vid: 28 iid: 1 pid: 20732 pub: Sage Publications Inc. place: Thousand Oaks, California artinfo: ui: 104520482 104520482 NLM22112549 2011463456 10.3233/JAD-2011-110719 NLM22112549 104520482 ppf: 885 ppct: 12 formats: tig: atl: Temporal integration of 3D coherent motion cues defining visual objects of unknown orientation is impaired in amnestic mild cognitive impairment and Alzheimer's disease. aug: au: Lemos R Figueiredo P Santana I Simoes MR Castelo-Branco M Lemos, Raquel Figueiredo, Patrícia Santana, Isabel Simões, Mário R Castelo-Branco, Miguel affil: IBILI, University of Coimbra, Coimbra, Portugal sug: subj: Alzheimer's Disease Physiopathology Cues Diagnostic Imaging Cognition Disorders Physiopathology Visual Perception Orientation Aged Aged, 80 and Over Alzheimer's Disease Diagnosis Amnesia Diagnosis Amnesia Physiopathology Case Control Studies Female Human Male Middle Age Cognition Disorders Diagnosis Physical Stimulation Prospective Studies Time Factors Aged: 65+ years Aged, 80 & over Middle Aged: 45-64 years Female Male ab: The nature of visual impairments in Alzheimer's disease (AD) and their relation with other cognitive deficits remains highly debated. We asked whether independent visual deficits are present in AD and amnestic forms of mild cognitive impairment (MCI) in the absence of other comorbidities by performing a hierarchical analysis of low-level and high-level visual function in MCI and AD. Since parietal structures are a frequent pathophysiological target in AD and subserve 3D vision driven by motion cues, we hypothesized that the parietal visual dorsal stream function is predominantly affected in these conditions. We used a novel 3D task combining three critical variables to challenge parietal function: 3D motion coherence of objects of unknown orientation, with constrained temporal integration of these cues. Groups of amnestic MCI (n = 20), AD (n = 19), and matched controls (n = 20) were studied. Low-level visual function was assessed using psychophysical contrast sensitivity tests probing the magnocellular, parvocellular, and koniocellular pathways. We probed visual ventral stream function using the Benton Face Recognition task. We have found hierarchical visual impairment in AD, independently of neuropsychological deficits, in particular in the novel parietal 3D task, which was selectively affected in MCI. Integration of local motion cues into 3D objects was specifically and most strongly impaired in AD and MCI, especially when 3D motion was unpredictable, with variable orientation and short-lived in space and time. In sum, specific early dorsal stream visual impairment occurs independently of ventral stream, low-level visual and neuropsychological deficits, in amnestic types of MCI and AD. pubtype: Academic Journal doctype: research Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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