A new functional biomarker of cognitive impairment in Alzheimer's disease: Neuroimaging / Optimal neuroimaging measures for early detection. (7th December 2020)

• Record Type: Journal Article
• Authors: Stothart, George; Smith, Laura
• Is Part Of: Alzheimer's & dementia. Volume 16(2020)Supplement 5
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-12-07
• Subjects: Alzheimer's disease -- Periodicals; Alzheimer Disease -- Periodicals; Dementia -- Periodicals; Démence; Maladie d'Alzheimer; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.83
• DOI: 10.1002/alz.041056
• Languages: English
• ISSNs: 1552-5260

Abstract

Abstract: Background: Fast Periodic Visual Stimulation (FPVS) provides a new objective electroencephalographic method for assessing an individual's ability to discriminate between different categories of stimuli. Participants do not need to understand the task, or provide any response, making it ideal for the assessment of cognition in patient populations. We have adapted FPVS to examine a range of cognitive processes that deteriorate in Alzheimer's disease, see Figure 1, with the ultimate aim of developing a functional biomarker to aid early diagnosis. Method: Healthy younger (n=42, ACE‐III=92 +‐ 6) and older adult controls (n=39, ACE‐III=95 +‐5), and Alzheimer's disease patients (n=20, ACE‐III=62+‐15) completed a battery of FPVS and behavioural tasks designed to measure their recognition memory, semantic categorisation and visual object processing, see Figure 2. Result: FPVS provided an objective measure of recognition memory, semantic categorisation and visual object processing in just 1min of EEG recording time with no behavioural response or comprehension of the task required. There were no significant differences between younger and older adults in any FPVS measures of cognitive function. Alzheimer's disease patients showed significant FPVS decreases in all three cognitive domains compared to healthy controls, with the greatest deficits in recognition memory (Old vs Alzheimer's, t (58)=3.68, p =0.001, Hedge's g = 1.38). FPVS measures of recognition memory separated AD from healthy ageing in binary classification approaches, outperforming behavioural measures, see Figure 3. Conclusion: We have demonstrated that FPVS can be adapted to measure a range of cognitive functions pertinent to dementia. It provides a fast, objective and implicit measure of cognitive function that remains stable in healthy ageing. Alzheimer's disease has a significant impact on FPVS measures of cognition, and the approach holds promise for the development of new early diagnosis tools.