When someone mentions Alzheimer’s disease, what do you think of? Memory loss and confusion. Maybe changes to mood. But what about visual impairments?
Many people don’t realize that Alzheimer’s (and other forms of dementia) can lead to problems with vision and perception. For those already suffering from confusion and communication issues, problems with sight can be a serious safety risk.
Here are 10 surprising ways Alzheimer’s might affect vision and how you can help:
1. Increased need for light – Alzheimer’s may cause your older adult’s pupils to react slowly to light. That means that if they’re looking out the window, for example, the room might appear pitch black when they turn back around. In addition, people with Alzheimer’s need two to three times more light than others.
When coupled with changes to gait and balance, these issues can cause a huge safety risk. Maintaining adequate lighting, as well as giving your loved one plenty of time to adjust, is essential.
2. Decreased color perception – As people age, there are often changes to color perception–but those with dementia seem to have an even greater deficit. For many, this means a reduced ability to perceive the vividness of colors (for instance, red may appear pink) and a possible inability to recognize blue colors. While this doesn’t prove a huge safety risk, it can make everyday tasks like coordinating an outfit more difficult.
3. Need for high contrast – In addition to not recognizing certain colors, recognizing gradients in color can be a problem in persons with Alzheimer’s. For example, if the bathroom floor, toilet, and walls are all white, they may not be able locate the toilet. Keeping a light on can help, but also make sure the walls are painted a color that contrasts with the toilet and other objects around it.
4. Need for visual simplicity – Those with dementia may have difficulty finding an object on a patterned background or identifying an object in a crowded scene. For example, it can be impossible to locate and pick up a pill that has been placed on a patterned tablecloth. Try setting the table with plain color cloths and placements that offer high contrast.
5. Tunnel vision – People’s field of vision narrows as they age, but for those with Alzheimer’s, it can narrow significantly. They may not be able to see to either side when gazing forward, resulting in clumsiness and confusion. Be aware that they may not be seeing everything that you see: For example, if you notice that your loved on has only eaten food on half the plate, try turning the plate around. In addition, be aware of their limited peripheral vision when you approach, so you don’t startle them.
6. Depth perception– Advanced dementia can cause the brain to only see from one eye, which affects the ability to determine distance, changes in elevation, or distinguish between three-dimensional and flat objects. Simple tasks like judging the depth of water in the bathtub or navigating thresholds and steps can become dangerous. Restricting the use of multi-focal lenses when walking can help avoid accidents.
7. Reduced ability to detect motion – Some people with Alzheimer’s are unable to detect movement. They view the world as a series of still photos, rather than a moving picture, like most people see it. This can make formerly enjoyable activities, like watching television or looking out a car window, unpleasant and disorienting.
8. Illusions – Illusions occur when a person views a physical object as something other than it actually is. For instance, a shiny spot on the floor may appear as a puddle or a dark spot may look like a hole. Illusions differ from hallucinations in that when an individual hallucinates, there is no physical object present. There is nothing that can be done to prevent illusions, but it is important to be understanding and accepting.
9. Misidentifications – As many as one in six people with Alzheimer’s may suffer from misidentifications – an upsetting issue for both them and their caregivers. Misidentifications occur when an individual is unable to identify certain objects or people. For example, they may believe that their husband is actually their brother, or a fluffy pillow might get called a “puppy”. These issues occur as a result of damage to the process linking the eyes to the brain and are not the same as delusions.
10. Mood – It’s quite common for people with dementia, especially Alzheimer’s, to become agitated and anxious in the late afternoon or early evening, a phenomenon known as “sundowning.” Increasing the artificial light in a room before the shadows get long seems to help.
Changes in vision may cause your loved on to act in a way that seems strange to you, but your older adult is just reacting to the world as they see it. Try to be patient and understand that things might be confusing, or even scary, for them.
For more information, visit the National Eye Institute (NEI) or the National Institute on Aging (NIH).