Visual problems in dementia

Increased life expectancy in the U.K. has lead to an increasingly ageing population. In turn, this is leading to an increasing prevalence of dementia.

Currently, there are estimated to be at least 700,000 people in the U.K. with some form of dementia: by 2025, this figure looks set to rise to 1 million.

Although dementia is more likely in the elderly population, it is not exclusively a disease of older people. According to a recent study by the Alzheimer’s society, there are in excess of 40,000 people in the U.K. below the age of 65 who have the condition.

There are several visual problems associated with dementia. These include loss of visual acuity (reduction in the level of vision), defects in colour vision, accuracy of eye movements and the disturbance of complex visual functions. Such functions include reading ability, visuospatial function (relating to, or being thought processes that involve visual and spatial awareness), and the naming and identification of objects.

Visual problems can result in impaired motion detection, impaired appreciation of 3D vision (stereopsis), and difficulties in the recognition of faces, objects and colour. Having difficulties with 3D vision can lead to problems with everyday tasks like climbing the stairs and placing objects down. Suffering with difficulties with orientation can mean people with dementia may experience symptoms such as bumping into things, misinterpreting reflections and getting lost in familiar surroundings. It can be particularly disturbing when a person with dementia views themselves in the mirror and does not recognise themselves, or sees a much younger version of themselves.

The Dementia Friends programme https://www.dementiafriends.org.uk  is a superb initiative to help transform people’s perception of dementia.