Shrinking Brain in Dementia
“What time is it?” asks the person with dementia.
“Five seconds since the last time you asked!” fumes the irritated caregiver.
Questions asked repeatedly can tax the patience of the most easy-going caregiver. It is a behavior that many formal and family caregivers find upsetting. Plus, caregivers are completely mystified how their spouse or parent or adult child (yes, there are moms and dads caring for adult children with dementia) cannot remember what they were just told, but can relate a memory from 30 years ago.
Brain nerve cells die off in Alzheimer’s disease and other types of dementia. The loss of nerve cells causes the brain to shrink. The medical term for shrinkage is “atrophy.” In the picture below, the brain on the left is showing significant atrophy or shrinkage, compared to the brain on the right.
One way to think of a healthy brain is that it is like a box. All of your memories are placed in the box. Your earliest memories are tucked away in the bottom. Your most recent memories are on top. So, imagine your brain as a large box filled with all of your memories. What would happen if that box started to shrink, started to slowly become smaller?
That’s right…as the box shrinks, the stuff inside falls out. The most recent memories, the ones at the very top, fall out and are lost. This is why a person with dementia may forget what he or she had for lunch, or may even deny having had lunch at all. This also explains why people with dementia can recall events from very long ago so clearly. As the most recent memories fall out of the box, the memories that were buried are now more accessible. In fact, people with dementia move backward in time. The memories from 40 plus years ago are now so vivid, they feel like they are reliving the memories, not just remembering.
This situation of vivid long-ago memories plus lost current memories creates a type of “new reality” for persons with dementia. These people are living in a world of their own memories that may be at odds with the present. If a box has shrunk, one cannot keep putting stuff into it. Likewise, as the brains of people with dementia shrink, they lose the ability to make new memories. That is why your family member may ask you “What time is it” every 5 minutes, or revisit the same topic constantly during a 15 minute conversation. They are not trying to be difficult. They are making the most of what memories they are able to get to.
These same memory problems may show up as care refusals. In your family member’s mind, he or she just bathed, even though you know he or she hasn’t had a bath in 2 weeks. They may also be living in a time period of their lives when they had no health problems, so you handing them a bunch of pills does not make sense. What high blood pressure? As the dementia becomes worse, and the box shrinks even more, they may mistake a son or daughter for a spouse, or even fail to recognize a loved one. This lack of recognition can create more refusals. Would you let some stranger take off your clothes and stand you naked in a shower?