Dementia/Alzheimer's as an Ancient Hibernation Response Triggered by Ever Present and Inescapable Chronic Stressors of Modern Life

Especially Chronic Loneliness, Isolation, Separation, Abandonment, and Grief

Introduction

I recently watched a very interesting podcast, and read a related article, about a new theory of Alzheimer’s. Although I don’t agree fully with the scientists’ conclusion, this was the final piece of the jigsaw for my own ideas around dementia, which I have been working on for some time. I can now summarize my own concept with the following proposal:

Some forms of dementia/Alzheimer’s are the outcome of the triggering of an ancient hibernation circuit in humans due to specific chronic stressors in modern life, namely chronic loneliness, isolation/separation, abandonment and loss/grief.

This is mainly based on my own empirical observations from living in a residential care home for a number of years, and seeing lots of people with different types and stages of dementia, as well as observing individuals progressively worsen and move through these stages.

From these observations, I group some folks with dementia into three main types or stages. Now, not every case of dementia of fits into these groupings, and so I am not saying my concept explains all forms of dementia, but just that these are commonalities among significant subgroupings.

1. The person is still relatively mobile, and can move around on their own. They constantly wander around, look to escape the building, or are searching for things, or family members. They may be violent or short tempered if interrupted in their searching. They are awake and can be interacted with. It is this stage which didn’t seem to fit my idea, until the above mentioned podcast and article put this piece of the jigsaw into place for me.

2. The person is no longer mobile and cannot move around on their own. They may display seeking behaviours to get attention, e.g. shouting out. They are partially reachable and can interact, but seem to be stuck in a waking dream, where time, memory and causality, and sense making are absent, as if they are in a REM sleep state. Indeed, they can display characteristics of RBD (rapid eye movement sleep disorder), including screaming, shouting, laughing, crying, arm flailing, kicking, punching.

3. The person appears to be in very deep sleep from which they cannot be woken, and they are no longer reachable, nor interactable with.

What is the new theory of Alzheimer’s covered in the podcast and article?

The quotes below are excerpts from the article.

“Johnson and his team suggest that Alzheimer’s is a harmful adaptation of an evolutionary survival pathway used in animals and our distant ancestors during times of scarcity.

When threatened with the possibility of starvation, early humans developed a survival response which sent them foraging for food. Yet foraging is only effective if metabolism is inhibited in various parts of the brain. Foraging requires focus, rapid assessment, impulsivity, exploratory behaviour and risk taking. It is enhanced by blocking whatever gets in the way, like recent memories and attention to time.”

Now this is what made sense of the type 1 behaviours I’ve observed, within my own re-framing of dementia, since:

“Johnson suspects that the tendency of some AD patients to wander off might be a vestige of the ancient foraging response.”

Where I differ from these scientists, however, is that, I my view the foraging response is only the first stage of a more complete ancient hibernation response. It is like just the hyperphagia phase of bears preparing for hibernation.

They propose that the worsening of Alzheimer’s, and hence the person eventually moving into type 2 and type 3 phases above, is due to those suffering getting stuck in the foraging response, and hence the parts of the brain, which are metabolically shutdown during foraging, atrophying. In contrast, in my version, if the foraging behaviour doesn’t resolve the chronic stressors in the environment, then the person’s brain and body proceeds into hibernation proper, to wait out the danger. As time goes on without resolution, the hibernation state becomes deeper. This is what I believe the type 2 and 3 stages actually represent. So instead of the body and brain going wrong, as in the scientists’ scenario, it is an adaptive and wise survival strategy in the ancestral context.

The second place I differ from the scientists is that, due to a convoluted argument about the role of fructose in the brain, they propose Alzhemier’s is entirely a function of poor diet. While diet may be a likely contributing factor to a cumulative or threshold effect of mounting chronic stressors, in my view, the craving for sweet food and drink which I have observed in type 1 folks (I have also observed hiding or caching of food, like animals preparing for hibernation also do), it seems to me that this is an effect of being in foraging stage, rather than the cause. Indeed, the scientists say as much themselves:

“Johnson suspects the survival response, what he calls the ‘survival switch’, that helped ancient humans get through periods of scarcity, is now stuck in the ‘on’ position in a time of relative abundance. This leads to the overeating of high fat, sugary and salty food prompting excess fructose production.”

Furthermore, a lack of food is not the only chronic stressor that our ancestors would have faced, and is very far from the actual threat we are facing today. Just as dangerous, and potentially lethal, would have been getting separated and isolated from the family or tribe, or being ostracized and abandoned. Thus separation could have resulted in the foraging/hibernation circuits getting switched on in a similar response to food shortages. Initially, the foraging response would cause the separated person to put all their effort and focus on searching for tribe members and safety. To paraphrase Johnson’s statement above,

“when threatened with the possibility of separation, early humans developed a survival response which sent them foraging for tribe members”.

I believe that this is what the type 1 behaviours are actually a manifestation of. Then, if the foraging is deemed unsuccessful, the body and brain goes into a hibernation state, to save any remaining energy in the last ditch hope the tribe will come back and find them.

In the modern world, where food is over-abundant, but we are more and more isolated and atomized, it is the separation as chronic stressor which is much more likely to be the major factor that is tripping the foraging/hibernation circuits to switch on. Indeed, loneliness is known to be a huge accelerant of dementia, as we saw during the pandemic, where deaths due to dementia skyrocketed.

In talking and listening to folks at the type 1 stage in the home here, about their lives, it is clear to me that they universally feel lonely, isolated, and especially abandoned by family members, and the decline often began after the loss of a loved one or a spouse, or family moving away, or a family dispute.

What is the evidence for hibernation in humans??

Firstly, it is important to say that the type of hibernation at play here, is not “obligate hibernation”, when some animals “spontaneously, and annually, enter hibernation regardless of ambient temperature and access to food”. It is “facultative hibernation”, which is entered “only when either cold-stressed, food-deprived, or… as a response to stressors from the environment”. As explored above, I think for our ancestral humans, separation from the tribe would also have been one of these stressors, on a par to food deprivation.

An example of a modern day hibernating primate is the fat tailed dwarf lemur of Madagascar, which hibernates in tree boles, not due to cold, or lack of food, but due to summer drought. Pertinent to my description of type 2 above

“during torpor, this lemur has been found to periodically enter REM sleep”.

Some anthropological research suggests early hominids may have hibernated.

That this can happen in modern days is illustrated by a famous case of a Swedish woman who slept for 32 years. However, a more recent and stark example is provided by the epidemic of kids of highly traumatized refugee families in Sweden, who, when the family is threatened to be returned to the country of origin, go to sleep and cannot awoken. There was a Netflix documentary made about this.

Another link between Alzheimer’s and hibernation has been made, in that hibernation demonstrates a hope that reversal is also possible:

“bears, hedgehogs and mice destroy brain connections as they enter hibernation, and repair them as they wake up.”

If I am correct about this, that the triggering of ancient hibernation circuits helps to explain some fraction of cases of dementia due to chronic loneliness/separation being the main chronic stressor which is switching these circuits on, then they way we treat and care for folks suffering due to this, requires a massive paradigm shift. This would include providing therapies like grief counselling, and making anyone with early signs feel embedded and valued in a supportive community, as a priority.

It would also further point to the scale of the horrors that were inflicted by the social distancing and isolation measures which were instigated during the pandemic. No wonder deaths due to dementia skyrocketed during the pandemic, and remain in high excess even today. If my concept is correct, this helps to underline why we must never do this again.