Eyesight in dementia - what might happen

As we age, we see a decline in our abilities, including vision. Dementia and eyesight are closely linked and it’s important we understand the implications of sensory loss in dementia. In this article, find out more about sight loss in dementia and the issues your loved one might be dealing with. 

Potential sight problems in dementia

Looking after loved one could be made easier if you are aware of how their eyesight might be affected. As dementia is the disease of the brain, and our brain processes all of our sensory perception, a person’s vision could become impaired. This manifests itself through the following: 

• Loss of depth perception – the person could have trouble distinguishing between a flat picture and a 3D object, as well as difficulties judging how far away the objects are. 

• Trouble detecting motion – dementia patient could perceive their surroundings as series of still images instead of a continuous ‘film’. 

• Narrow field of vision – our peripheral vision narrows as we age, however, for people in dementia care, this change could be much more dramatic. This can cause them to perceive the world as if through binoculars, resulting in disorientation and confusion.

• Colour perception and contrast sensitivity – people with dementia may struggle to perceive colours and distinguish between objects of similar colour. Locating the loo in an all-white bathroom could become a problem, as well as recognising food on the plate and co-ordinating their clothes. 

• It’s easy to see how these changes in vision will affect a person’s daily life. They may struggle with reading, writing, watching television as well as recognising friends and family. Illusions, misperceptions and misidentifications could become a regular occurrence. The person may be startled by someone approaching them, their ability to perform daily tasks could become affected, confusion and disorientation become more frequent. It’s important that your loved one’s vision is checked regularly, and any treatable issues are addressed, as their behaviours could be confused with symptoms of dementia. 

Sight loss and behavioural changes

As a carer, it’s crucial to understand the issues associated with reduced vision or becoming sightless in dementia. The patient might be reaching out for things they perceive to be much closer or trying to pick something off the floor that isn’t there, which comes across as strange behaviour. It’s vital that you understand it could be caused by a decline in their eyesight and are able to assist where it is necessary. Knowing that these issues relate to sight loss will reduce worries that your loved one is behaving irrationally. Vision impairment could also increase their risk of falls, as well as causing difficulty adjusting from light to dark spaces and vice versa, so it’s critical that such problems are dealt with and their risk of injuring themselves is reduced. The person may become even more anti-social, so it’s important that isolation is prevented through social activities and directing attention to enjoyable hobbies like listening to the radio or music. Activities that stimulate other senses such as getting a manicure or hand massage, or holding onto objects with varied and pleasant textures could also be helpful.