Seeing is believing, yes? In our day-to-day world, we believe that what we see around us is pretty much what others with healthy eyes can see. We see a clear glass filled with milk sitting on a white table, and we assume that others can see a clear glass filled with milk sitting on a white table, too.
But that’s not necessarily true if someone has Alzheimer’s Disease — they may only see the white table. Though it is not widely recognized, it is a fact that people with several types of dementia (but especially Alzheimer’s Disease) experience significant changes in the way their brains take in and interpret visual information, generally unconnected to eye health and function. These changes follow several predictable patterns that powerfully influence the behavior of people with dementia.
In this, Part 3 of a series of articles on Habilitation Therapy (HT) for Alzheimer’s Disease and other dementias (ADRD), we focus on how this loss of function in the visual cortex of the brain helps us better understand a person with dementia. HT focuses on helping dementia patients function at the best of their still-present abilities, instead of trying to return lost functioning to them. (It is Rehabilitation Therapy that returns lost functioning; regaining former abilities is not known to be possible with ADRD.) (Alzheimer’s Association, 2011) Habilitation Therapy can be applied with enormous effectiveness to the difficulties that arise from these changes in visual processing.
In HT, care partners do their best to enter into the dementia patient’s reality, and to see the world through their eyes. (Alzheimer’s Association, n.d., p. 138) When it comes to vision and dementia, this is quite literal: we must understand visual processing changes to help the patient’s functioning and reduce or eliminate difficult behaviors.
Seven Types of Major Visual Changes
- Inability to perceive dimensionality. People with Alzheimer’s Disease lose the ability to see and judge depth correctly. A light fixture flush with a nine-foot-high ceiling may seem to them to be reachable while standing on the floor, no stepstool needed. A stripe of black linoleum visible around the edges of a light carpet can be interpreted to be a bottomless pit they must not fall into.
- Shrinking peripheral vision. By mid-disease, Alzheimer’s patients have the equivalent of tunnel vision. Occupational therapist and dementia expert Teepa Snow suggests we can experience how limited a view this is by using “binoculars” like a child would create with his or her hands. Do this by loosely circling fingers to make two tunnels through which to peer. By putting the circled fingers to our eyes like binoculars, we get a good estimation of this limited view; the field of vision is about 12” in diameter in all directions. (Snow, n.d.) This means the Alzheimer’s patient cannot see something unless it is directly in front of them at just about eye level.
- High color contrast. Go back to the example at the beginning of this article: a clear glass filled with milk on a white table. Alzheimer’s patients need high contrast to discern one object from another. They may not notice a glass of milk on a table unless the table and milk are distinctly different colors – for example, chocolate milk on a white table would be easier to see.
- Need for brighter lighting. Normal aging brings about the need for brighter lighting for most people. Enhanced lighting is even more imperative for people with Alzheimer’s. Dr. Paul Raia, one of the founders of HT, recommends significantly increasing the intensity of normal household lighting from 30-foot-candle power, to 60- or 70-foot-candle power. (Raia, 2011, p. 2)
- Trouble with glare and shadows. “Sundowning” – the exacerbation of difficult behaviors as sunset approaches – is not well understood, but is not uncommon in dementia. One theory is that glare and lengthening shadows caused by the sun’s lower angle might be confusing to people with dementia. Pulling shades or curtains and providing steady, bright lighting for some people can be helpful to avoid or diminish such episodes. (Raia, 2011, p. 2)
- Need for greater simplicity. Visual complexity can be difficult for the dementia patient to interpret. For example, multiple overlapping visual patterns can become a swirl of confusion. The same goes for the normal clutter in so many homes. Such visual “noise” makes it difficult for the dementia patient to organize their thinking and activities, thereby reducing their ability to function.
- Right eye preference. In some types of dementia, the brain may stop or reduce processing information taken in by the left eye. This is why some dementia patients may, for example, say that they are hungry when the left side of their dinner plate still contains more food. (Snow, n.d.)
Knowing now about these significant changes people with dementia experience in their ability to see and understand what they see, it is easy to understand how they struggle to get through each day. There is much confusing or missing information about their immediate environment – information they previously had. Because their cognition and judgement also are damaged, it may be impossible to teach dementia patients strategies for operating with confused and diminished vision. Their resulting difficult behavior might be considered a fully normal reaction to a highly abnormal situation.
People with dementia cannot leave the reality they live in; care partners must join them there. Yet, most family and caregivers do not know about the profound and sweeping changes in visual perception that happen in people with dementia. Even though Alzheimer’s is the most commonly diagnosed type of dementia, and its visual changes are highly common, they remain one of its biggest secrets. (Alzheimer’s Association, 2011b)
By understanding and anticipating the vision changes experienced by people with Alzheimer’s, Habilitation Therapy can help care partners make simple, effective adaptations to the physical environment. These changes are all intended to enhance the patient’s ability to function more independently, which has an enormous positive impact on everyone’s emotional well-being.
Alzheimer’s Association, Massachusetts/New Hampshire Chapter. (n.d.) Caring for People with Alzheimer’s Disease: A Habilitation Training Curriculum. Watertown, MA: Alzheimer’s Association.
Alzheimer’s Association, Massachusetts/New Hampshire Chapter. (August 2, 2011) Caring for People with Alzheimer’s Disease: A Habilitation Training Curriculum [Training Course]. Lawrence, MA: Alzheimer’s Association.
Alzheimer’s Association. (2011b). 2011 Alzheimer’s Disease Facts and Figures. Alzheimer’s & Dementia, Volume 7, Issue 2.
Raia, P. (Fall, 2011) Habilitation Therapy in Dementia Care. Age in Action. Vol. 25, No. 4.
Snow, T. (n.d) The Art of Caregiving. [Video] Florida: Pines Education Institute of Southwest Florida.