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Clues About Consciousness from Dementia Research

Photo credit: Laura Fuhrman via Unsplash.

Researchers have begun to ask about the curious fact that persons with obvious dementia sometimes have lucid episodes:

In the last week, Sarah has occasionally said things that were recognizable, startling her family. Most notably, on two occasions, she clearly and unexpectedly told her spouse, “I’m scared. I want you to come with me.” These episodes unsettled him. He reported them to Sarah’s physician, asking for advice. (This case is adapted from one of the author’s [JK] clinical experiences.)

Peterson A, Clapp J, Largent EA, Harkins K, Stites SD, Karlawish J. What is paradoxical lucidity? The answer begins with its definition. Alzheimers Dement. 2022 Mar;18(3):513-521. doi: 10.1002/alz.12424. Epub 2021 Aug 2. PMID: 34338400; PMCID: PMC8807788. The paper is open access.

The Mystery of Paradoxical Lucidity 

It’s called “paradoxical lucidity because it is unexpected and we know very little about its causes. Documented cases are even causing researchers to question what we do know about dementia. From the Penn Memory Center:

How can a person living with advanced dementia abruptly communicate in a clear manner? Many wonder what mechanism underlies this phenomenon and if it might be a key to mitigating — or even reversing — neurodegeneration. It’s also a mystery whether people who exhibit these episodes are aware when they happen, and how that might affect dementia care.

Cait Kearney, “Penn researchers study a phenomenon that makes them question what we know about dementia,” Penn Memory Center, March 30, 2022

One difficulty is, people lose interest in and contact with friends and relatives who suffer from dementia. Thus their moments of lucidity may go entirely unnoticed. As a result, they are are understudied.

One research team notes the contrast with what happens when the person with dementia is actually dying. Family and professionals may easily remember sudden insights (terminal lucidity). But chances are, if such awareness had happened several times earlier in the same year, the deathbed witnesses were not around when it happened.

That’s a Problem for Two Reasons

According to Parnia Lab, which is conducting a five-year study of the phenomenon, dementia may affect 75 million people by 2030. But the reality is that current treatments for the disorder are showing only fits and starts of progress. As Andrew Peterson et al. explain, “Systematic investigation could shed light on its clinical manifestation and underlying neurobiology, which may pave the way for novel therapies that reverse impairments caused by neurodegenerative diseases.” That’s worth thinking about in an age when in Canada, for example, euthanasia is becoming accepted as the solution for dementia.

Those of us who reject that approach might begin by rethinking the problem. Stephen Post, Director of the Center for Medical Humanities, Compassionate Care and Bioethics at Stony Brook University, prefers to call people struggling with dementia “deeply forgetful,” which is reflected in the title of his 2022 book, Dignity for Deeply Forgetful People (Johns Hopkins University Press). Elsewhere, he has written,

In the lives of carers for the deeply forgetful, hope might be best defined as an openness to surprises … The idea of hope as “being open to surprises” is not something this author simply dreamed up. It emerges from 20 years of working with carers in support groups and community dialogues. Yes, there is an assault on the story of a life, but despite the losses, there are also sporadic indicators of continuing self-identity that make caring meaningful.

Post SG. Hope in caring for the deeply forgetful: enduring selfhood and being open to surprises. Bull Menninger Clin. 2013 Fall;77(4):349-68.

Here’s a Surprise

Could we capture those sudden moments of lucidity via brain imaging and pinpoint their neural correlates? What is happening in the brain at the same time? Is it something that changed care routines or treatments could prolong or make more frequent, as Andrew Peterson et al. hope? Given the amount of time, energy, and money that has been spent on other approaches that haven’t been very fruitful, it’s only fair to give this one a try.

That, of course, means addressing the reality that, even if treatments that use paradoxical lucidity as a base camp are shown to work, the lucidity they create may remain somewhat mysterious — like consciousness itself. But researchers should surely be glad to live with such a creative mystery.

Cross-posted at Mind Matters News.