Abnormalities of saccadic eye movements in dementia due to Alzheimer's disease and mild cognitive impairment.

Background: There is increasing evidence that people in the early stages of Alzheimer's disease (AD) have subtle impairments in cognitive inhibition that can be detected by using relatively simple eye-tracking paradigms, but these subtle impairments are often missed by traditional cognitive assessments. People with mild cognitive impairment (MCI) are at an increased likelihood of dementia due to AD. No study has yet investigated and contrasted the MCI subtypes in relation to eye movement performance. Methods: In this work we explore whether eye-tracking impairments can distinguish between patients with the amnesic and the non-amnesic variants of MCI. Participants were 68 people with dementia due to AD, 42 had a diagnosis of aMCI, and 47 had a diagnosis of naMCI, and 92 age-matched cognitively healthy controls. Results: The findings revealed that eye-tracking can distinguish between the two forms of MCI. Conclusions: The work provides further support for eye-tracking as a useful diagnostic biomarker in the assessment of dementia.