Dementia-related illness causes many changes in the brain including damage to the visual-perception system—or how the brain processes what the eyes see. In many cases there is no change in eye health but only in the way the brain interprets the vision field. This can dramatically alter a dementia patient’s perception of the world and how they understand it, which can lead to anxiety, fear and unusual behaviour.

If you are caring for a loved one with dementia, appreciating how their vision could be affected and the type of behaviours you may see because of these changes can be very helpful. Read on for the most common problem areas and helpful adaptations for each challenge.

DEPTH PERCEPTION

A decline in the ability to process distance can make it difficult for dementia patients to judge how far away an object is. This can cause collisions with objects and people, difficulty navigating stairs or flooring changes (e.g., tile to wood) and trouble distinguishing between two- or three-dimensional objects.

These changes can also cause odd behaviours such as: grabbing at the air instead of making contact with a light switch, attempting to pick up a flower on a floral tablecloth or worrying about the depth of water during bath time.

How to Help:

• Keep areas around the house well lit.
• Apply brightly coloured tape or textured strips to stair edges.
• Hardwood or plain carpeting is always best for dementia patients. Remove any throw rugs. If required, make sure any area rugs are not patterned and are safely secured.
• Keep regularly used areas around the home clutter-free and avoid rearranging furniture.
• Be patient and regularly reassure your loved one. Walk across a floor surface or place a clean foot in the tub to demonstrate the depth.
• Remove or cover mirrors which often cause depth perception issues.

REDUCED PERIPHERAL RANGE

With age, we naturally experience a narrowing of the field of vision, but this ‘tunnel vision’ can be quite significant for dementia patients. Experts say that it can feel like wearing binoculars or looking through a tube. The brain changes that occur with dementia can also lead patients to only process information from one eye, typically the right one.

As a result, those with dementia may not see people approaching from the side, they may trip or bump into things, they can struggle in crowded places or in areas with low lighting and only be aware of what is right in front of them.

How to Help:

• Let your loved one know when you enter a room and stand in front of them before you speak.
• Always place needed objects directly in front of your loved one.
• Rotate their plate at mealtimes to encourage eating from both sides.
• Remove clutter from floors, hallways and tables.

COLOUR AND CONTRAST DECLINE

These changes can also affect a dementia patient’s ability to differentiate between colours or subtle differences in their environment. This means that the person in your care may find it difficult to see objects that are the same or a similar colour and struggle to distinguish between horizontal and vertical surfaces.

It can also be difficult for people with dementia to see large panes of glass which can lead to accidents and injuries. Creating more (or sometimes less) contrast between objects can be beneficial.

How to Help:

• Bathroom sinks, toilets and other fixtures should contrast with the walls and floor. Add a coloured toilet seat, and if painting is an option, paint the bathroom walls.
• If wandering is a concern, paint exit doors the same colour as the walls so they are more concealed.
• Cover couches and chairs with bright sheets or use a colourful tablecloth on the kitchen table to make furniture stand out.
• Hang wall art or tapestries to help differentiate the walls from the floors.
• Use a bright placemat under a white plate or select a darker plate for lighter foods like mashed potatoes or toast. Replace clear drinking cups with coloured ones and consider coloured utensils.
• Add removable decals on shower doors, patio doors and windows to prevent collisions.

In some cases, vision changes can be unrelated to dementia and may be caused by cataracts or other age-related decline. Always make sure that your loved one has regular eye exams and that any glasses prescriptions are correct. Any changes in vision can make dementia confusion and disorientation worse.

It is often helpful for caregivers to understand how these changes in vision and perception can be scary and stressful for the person in their care. Modifying the home environment as outlined above will help keep loved ones safe, reduce difficult behaviours like aggression and agitation and also help promote as much autonomy and independence as possible.

Visit VHA Home HealthCare’s Dementia Care resource if you need in-home support or for more ways to keep your loved one safe and healthy.

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If you found this article helpful, you may also want to read:

• Compassionate Care Strategies Using the 7 ‘A’s of Dementia
• Dementia and Aggressive Behaviour