Visuoperceptual Impairment

Visuoperceptual distortions are problems that involve both vision and perception. Common mistakes are illusions (seeing a face in a shadow), misperceptions (mistaking a stain on the carpet for a hole), and misidentifications (difficulties distinguishing daughter from grandaughter).

Understandably caregivers might mistake these distortions as delusions. But it is important to know that what the person with dementia is experiencing is not a true delusion. It is not based on incorrect reasoning or delusional thinking. Rather, it is the result of damage to neuro-visual system. Consequences include but are not limited to:

• needing more time to adapt to changes in light levels (eg when going from a dark room into sunlight or viceversa)
• changes in the reaction of the pupil to light
• loss of peripheral vision (being able to see things outside of the direct line of vision),
• reduced ability to differentiate colours
• problems directing or changing gaze
• problems with the recognition of objects, faces and colours
• loss of ability to name what has been seen
• double vision
• problems with depth perception.

As a result a person  may:

• become lost or disorientated, even in familiar places
• have problems locating people or objects
• misinterpret reflections (i.e. seeing an 'intruder' or refusing to go into a bathroom because it appears occupied, mistaking images on the TV for real people).

Regular eye examinations are important since cataracts, glaucoma, macular degeneration and retinal complications from diabetes also cause visuoperceptual distortions.

As a caregiver, the best approach is not to point out or correct distortions unless they are disturbing to the person experiencing them.

What a big store!

So Opa and I have added a new activity: Sunday night grocery shopping at Walmart. He likes it because there aren't too many people and we can always get parking close to the store. But the thing that impresses him the most is the store's size. Each time we go there he marvels, "What a big store!"

Tonight Opa must have been particularly impressed because even on the way home while waiting at a traffic light, he said: "What a big store! Huge!"

Noticing that I failed to share his amazement, Opa pointed to the next set of traffic lights about half a kilometre down the road. "Unbelievable!" he said. "Look at the light at the back of the store! Can you see it? This store is huge!"

I got with the picture then, commented on the hugeness of what we were seeing, and how good Opa's eyesight is for a person of 85 years. Once we started driving again, Opa talked about how satisfied he is with his life. As we pulled into our driveway, I asked him if I had told him lately what a great person he is. He answered with a grin, "Yes, but I wouldn't mind hearing it again!"

So there's the bitter-sweetness of life with Opa. There are daily indications of continued cognitive decline, like this visuoperceptual difficulty, and reminders of mortality and change and the shortness of time. But there is also humour and tenderness.  I think to myself, the more accepting I can be of death, my own as well as Opa's, the freer and more open I am to the beauty of our shared experience.