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

Abstract

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.

The Disengagement of Visual Attention: An Eye-Tracking Study of Cognitive Impairment, Ethnicity and Age

“…People with amnesic MCI are at a greater risk of progressing to dementia [ 45 , 46 , 47 ]. Recently, our lab has shown that these errors are also evident in amnesic MCI to a greater extent than non-amnesic MCI participants [ 20 ]. We have argued that this error correction implicates a neural network that includes the anterior cingulate.…”

“…Mounting research has demonstrated that the attentional operations used in eye tracking tasks can provide an early marker of neurodegenerative disease [ 15 , 16 , 17 , 18 , 19 , 20 ]. Importantly, eye movement abnormalities occur earlier than the more noticeable changes in memory, which present relatively late in the progression of the disease [ 21 ].…”

Assessing Saccadic Eye Movements With Head-Mounted Display Virtual Reality Technology

“…Those with Alzheimer's Disease (AD) and amnestic MCI (aMCI) also exhibited significantly longer response time in the anti-saccade task compared to non-aMCI population and healthy controls. More errors were also observed in people with AD and aMCI (11). Obliquely oriented microsaccades were often seen in people with AD and aMCI (8).…”

“…Ocular movements can be subcategorized into two clauses: 1) fixation, blink, vergence, smooth pursuit, vestibuloocular reflexes, optokinetic nystagmus, and pupillary responses, and 2) saccade (7,9). While it is important to evaluate eye movements with combining these subcategorized events (9), saccadic eye movement is often assessed in various neurodegenerative disorders; e.g., in dementia (11).…”

Afferent and Efferent Visual Markers of Alzheimer’s Disease: A Review and Update in Early Stage Disease

“…Most interestingly, Wilcockson et al ( 2019 ) were the first group to study saccadic eye movement within MCI subtypes. They found that the antisaccade error rate is significantly higher in those with amnestic MCI compared to those with non-amnestic MCI and was negatively associated with memory score as measured by the free and cued selective reminding test free recall ( Table 3 , Wilcockson et al, 2019 ).…”