Neurophysiological and perceptual correlates of navigational impairment in Alzheimer's disease

Voyko Kavcic, Roberto Fernandez, David Logan, Charles J. Duffy

Research output: Contribution to journalArticle

60 Citations (Scopus)

Abstract

We assessed visual processing related to navigational impairment in Alzheimer's disease hypothesizing that visual motion evoked responses to optic flow simulating observer self-movement would be linked to navigational performance. Mild Alzheimer's disease and older adult control subjects underwent open-field navigational testing, visual motion perceptual threshold determination and a battery of neuropsychological examinations. We recorded visual motion evoked potentials (EPs) at occipital and parietal sites during centred visual fixation. Randomly moving or stationary pattern pre-stimuli preceded horizontal motion and radial optic flow stimuli to separate motion N200s from pattern onset responses. Radial optic flow evoked N200 responses comparable with those obtained with uniform horizontal motion, despite the variety of motion directions in radial optic flow. Alzheimer's disease patients showed smaller radial optic flow N200s than older adult subjects, and these were greatly diminished when preceded by stationary dots. Combining N200 amplitudes with optic flow perceptual thresholds and contrast sensitivities yielded a strong correlation with navigational impairment in Alzheimer's disease (R 2 = 0.95). We conclude that navigational impairment in Alzheimer's disease is linked to a disorder of extrastriate visual cortical motion processing reflected in specific perceptual and neurophysiological measures.

Original languageEnglish (US)
Pages (from-to)736-746
Number of pages11
JournalBrain
Volume129
Issue number3
DOIs
StatePublished - Mar 1 2006

Fingerprint

Optic Flow
Alzheimer Disease
Visual Evoked Potentials
Contrast Sensitivity
Vision Disorders

All Science Journal Classification (ASJC) codes

  • Clinical Neurology

Cite this

Kavcic, Voyko ; Fernandez, Roberto ; Logan, David ; Duffy, Charles J. / Neurophysiological and perceptual correlates of navigational impairment in Alzheimer's disease. In: Brain. 2006 ; Vol. 129, No. 3. pp. 736-746.
@article{9d8964abf1d3442e8f3eaffefde3f6f6,
title = "Neurophysiological and perceptual correlates of navigational impairment in Alzheimer's disease",
abstract = "We assessed visual processing related to navigational impairment in Alzheimer's disease hypothesizing that visual motion evoked responses to optic flow simulating observer self-movement would be linked to navigational performance. Mild Alzheimer's disease and older adult control subjects underwent open-field navigational testing, visual motion perceptual threshold determination and a battery of neuropsychological examinations. We recorded visual motion evoked potentials (EPs) at occipital and parietal sites during centred visual fixation. Randomly moving or stationary pattern pre-stimuli preceded horizontal motion and radial optic flow stimuli to separate motion N200s from pattern onset responses. Radial optic flow evoked N200 responses comparable with those obtained with uniform horizontal motion, despite the variety of motion directions in radial optic flow. Alzheimer's disease patients showed smaller radial optic flow N200s than older adult subjects, and these were greatly diminished when preceded by stationary dots. Combining N200 amplitudes with optic flow perceptual thresholds and contrast sensitivities yielded a strong correlation with navigational impairment in Alzheimer's disease (R 2 = 0.95). We conclude that navigational impairment in Alzheimer's disease is linked to a disorder of extrastriate visual cortical motion processing reflected in specific perceptual and neurophysiological measures.",
author = "Voyko Kavcic and Roberto Fernandez and David Logan and Duffy, {Charles J.}",
year = "2006",
month = "3",
day = "1",
doi = "10.1093/brain/awh727",
language = "English (US)",
volume = "129",
pages = "736--746",
journal = "Brain",
issn = "0006-8950",
publisher = "Oxford University Press",
number = "3",

}

Neurophysiological and perceptual correlates of navigational impairment in Alzheimer's disease. / Kavcic, Voyko; Fernandez, Roberto; Logan, David; Duffy, Charles J.

In: Brain, Vol. 129, No. 3, 01.03.2006, p. 736-746.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Neurophysiological and perceptual correlates of navigational impairment in Alzheimer's disease

AU - Kavcic, Voyko

AU - Fernandez, Roberto

AU - Logan, David

AU - Duffy, Charles J.

PY - 2006/3/1

Y1 - 2006/3/1

N2 - We assessed visual processing related to navigational impairment in Alzheimer's disease hypothesizing that visual motion evoked responses to optic flow simulating observer self-movement would be linked to navigational performance. Mild Alzheimer's disease and older adult control subjects underwent open-field navigational testing, visual motion perceptual threshold determination and a battery of neuropsychological examinations. We recorded visual motion evoked potentials (EPs) at occipital and parietal sites during centred visual fixation. Randomly moving or stationary pattern pre-stimuli preceded horizontal motion and radial optic flow stimuli to separate motion N200s from pattern onset responses. Radial optic flow evoked N200 responses comparable with those obtained with uniform horizontal motion, despite the variety of motion directions in radial optic flow. Alzheimer's disease patients showed smaller radial optic flow N200s than older adult subjects, and these were greatly diminished when preceded by stationary dots. Combining N200 amplitudes with optic flow perceptual thresholds and contrast sensitivities yielded a strong correlation with navigational impairment in Alzheimer's disease (R 2 = 0.95). We conclude that navigational impairment in Alzheimer's disease is linked to a disorder of extrastriate visual cortical motion processing reflected in specific perceptual and neurophysiological measures.

AB - We assessed visual processing related to navigational impairment in Alzheimer's disease hypothesizing that visual motion evoked responses to optic flow simulating observer self-movement would be linked to navigational performance. Mild Alzheimer's disease and older adult control subjects underwent open-field navigational testing, visual motion perceptual threshold determination and a battery of neuropsychological examinations. We recorded visual motion evoked potentials (EPs) at occipital and parietal sites during centred visual fixation. Randomly moving or stationary pattern pre-stimuli preceded horizontal motion and radial optic flow stimuli to separate motion N200s from pattern onset responses. Radial optic flow evoked N200 responses comparable with those obtained with uniform horizontal motion, despite the variety of motion directions in radial optic flow. Alzheimer's disease patients showed smaller radial optic flow N200s than older adult subjects, and these were greatly diminished when preceded by stationary dots. Combining N200 amplitudes with optic flow perceptual thresholds and contrast sensitivities yielded a strong correlation with navigational impairment in Alzheimer's disease (R 2 = 0.95). We conclude that navigational impairment in Alzheimer's disease is linked to a disorder of extrastriate visual cortical motion processing reflected in specific perceptual and neurophysiological measures.

UR - http://www.scopus.com/inward/record.url?scp=33244493744&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33244493744&partnerID=8YFLogxK

U2 - 10.1093/brain/awh727

DO - 10.1093/brain/awh727

M3 - Article

C2 - 16461482

AN - SCOPUS:33244493744

VL - 129

SP - 736

EP - 746

JO - Brain

JF - Brain

SN - 0006-8950

IS - 3

ER -