Visual-spatial deficits expalin visual symptoms in Alzheimer's disease
C M Butter1, J D Trobe, N L Foster
1Department of Psychology, University of Michigan, Ann Arbor, USA.
American Journal of Ophthalmology
|July 1, 1996
Summary
Visual symptoms in Alzheimer's disease (AD) are linked to visual-spatial deficits. Early screening for AD should focus on assessing these specific visual-spatial skills.
Area of Science:
- Neuroscience
- Ophthalmology
- Cognitive Science
Background:
- Alzheimer's disease (AD) is a neurodegenerative disorder.
- Visual symptoms are reported in some AD patients.
- The underlying cause of visual symptoms in AD is not fully understood.
Purpose of the Study:
- To investigate the relationship between visual symptoms and visual-spatial dysfunction in Alzheimer's disease.
- To determine if visual-spatial deficits are a primary cause of visual symptoms in AD patients.
Main Methods:
- Administered a neuropsychometric test battery assessing visual-spatial skills, form identification, color vision, and visual memory.
- Compared three groups: AD patients with prominent visual symptoms, AD patients without visual symptoms, and a control group.
- Matched AD groups by Wechsler Adult Intelligence Scale-Revised scores.
Main Results:
- Patients with Alzheimer's disease and prominent visual symptoms showed significantly poorer visual-spatial test scores compared to those without visual symptoms.
- No other significant differences were noted between the AD groups on the tested visual functions.
Conclusions:
- Visual symptoms in Alzheimer's disease are primarily associated with visual-spatial deficits.
- Findings suggest partially segregated brain pathways for visual-spatial and form identification.
- Screening tools for visually symptomatic AD patients should emphasize visual-spatial assessments.
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