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Functional Magnetic Resonance Imaging (fMRI) of the Visual Cortex with Wide-View Retinotopic Stimulation
Published on: December 8, 2023
Alzheimer disease: functional abnormalities in the dorsal visual pathway
Arun L W Bokde1, Patricia Lopez-Bayo, Christine Born
1Discipline of Psychiatry, School of Medicine and Trinity College Institute of Neuroscience, Laboratory of Neuroimaging and Biomarker Research, Trinity College Dublin, Adelaide and Meath Hospital incorporating National Children's Hospital, Dublin, Ireland. Arun.Bokde@tcd.ie
Radiology
|December 25, 2009
Summary
Patients with Alzheimer disease (AD) show altered brain activation in the dorsal visual pathway compared to healthy controls (HC). This suggests the dorsal pathway may be more vulnerable to AD neuropathology.
Area of Science:
- Neuroscience
- Neuroimaging
- Alzheimer Disease Research
Background:
- Alzheimer disease (AD) is a neurodegenerative disorder.
- Visual pathway alterations may occur in AD.
- The dorsal visual pathway's role in AD is not fully understood.
Purpose of the Study:
- To investigate neural activation differences in the dorsal visual pathway between patients with mild Alzheimer disease (AD) and age-matched healthy controls (HC).
- To compare brain activation during face and location matching tasks.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was used to measure brain activation.
- Twelve patients with mild AD and 14 HC subjects participated.
- Statistical analyses employed mixed-effects models with corrections for multiple comparisons.
Main Results:
- No significant differences in task performance were observed between AD patients and HC subjects.
- Healthy controls showed selective activation of visual pathways.
- Alzheimer disease patients exhibited non-selective activation and recruited additional brain regions in the dorsal pathway during location matching.
Conclusions:
- Altered dorsal visual pathway activation in AD may indicate a compensatory mechanism for reduced processing efficiency.
- The dorsal visual pathway appears more susceptible to AD-related neuropathological changes than the ventral visual pathway.
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