Eye-tracking indices of impaired encoding of visual short-term memory in familial Alzheimer’s disease

Ivanna M. Pavisic*, Yoni Pertzov, Jennifer M. Nicholas, Antoinette O’Connor, Kirsty Lu, Keir X.X. Yong, Masud Husain, Nick C. Fox, Sebastian J. Crutch

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

16 Scopus citations

Abstract

The basis of visual short-term memory (VSTM) impairments in preclinical Alzheimer’s disease (AD) remains unclear. Research suggests that eye movements may serve as indirect surrogates to investigate VSTM. Yet, investigations in preclinical populations are lacking. Fifty-two individuals from a familial Alzheimer’s disease (FAD) cohort (9 symptomatic carriers, 17 presymptomatic carriers and 26 controls) completed the “Object-localisation” VSTM task while an eye-tracker recorded eye movements during the stimulus presentation. VSTM function and oculomotor performance were compared between groups and their association during encoding investigated. Compared to controls, symptomatic FAD carriers showed eye movement patterns suggestive of an ineffective encoding and presymptomatic FAD carriers within 6 years of their expected age at symptom onset, were more reliant on the stimuli fixation time to achieve accuracy in the localisation of the target. Consequently, for shorter fixation times on the stimuli, presymptomatic carriers were less accurate at localising the target than controls. By contrast, the only deficits detected on behavioural VSTM function was in symptomatic individuals. Our findings provide novel evidence that encoding processes may be vulnerable and weakened in presymptomatic FAD carriers, most prominently for spatial memory, suggesting a possible explanation for the subtle VSTM impairments observed in the preclinical stages of AD.

Original languageAmerican English
Article number8696
JournalScientific Reports
Volume11
Issue number1
DOIs
StatePublished - Dec 2021

Bibliographical note

Publisher Copyright:
© 2021, The Author(s).

Fingerprint

Dive into the research topics of 'Eye-tracking indices of impaired encoding of visual short-term memory in familial Alzheimer’s disease'. Together they form a unique fingerprint.

Cite this