Looking but not seeing: Increased eye fixations in behavioural-variant frontotemporal dementia

Abstract

Face processing plays a central role in human communication, with the eye region a particularly important cue for discriminating emotions. Indeed, reduced attention to the eyes has been argued to underlie social deficits in a number of clinical populations. Despite well-established impairments in facial affect recognition in behavioural-variant frontotemporal dementia, whether these patients also have perturbed facial scanning is yet to be investigated. The current study employed eye tracking to record visual scanning of faces in 20 behavioural-variant frontotemporal dementia patients and 21 controls. Remarkably, behavioural-variant frontotemporal dementia patients displayed more fixations to the eyes of emotional faces, compared to controls. Neural regions associated with fixations to the eyes included the left inferior frontal gyrus, right cerebellum and middle temporal gyrus. Our study is the first to show such compensatory functions in behavioural-variant frontotemporal dementia and suggest a feedback-style network, including anterior and posterior brain regions, is involved in early face processing.