Alzheimer’s disease may cause us to forget faces, where we left familiar objects… even where we are… because our brains cannot find where we put those memories!

At least that’s what a new study suggests.

The study, reported in Nature1, challenges the assumption that Alzheimer’s prevents the brain from making new memories. It also suggests that brain stimulation may temporarily improve  memories in early stages of the disease.

This new research enhances earlier work by lead author Susumu Tonegawa, a neuroscientist, and his colleagues at MIT in Cambridge. Last year, they showed that in certain types of amnesia, memories were stored but could not be retrieved2.

It’s hard to detect what is a  stored and what is a retrieved memory . The only way to test a memory is to ask a patient to recall it.
Memories can be manipulated in mice, so Tonegawa and colleagues tested their theory using two strains of mice with mutations in genes linked to Alzheimer’s disease.

These mice develop amyloid protein clusters, or plaques, in their brains and eventually lose their memories — just like humans. The team were able to  demonstrate this memory loss by placing the mice in a box in which they received an electric shock. (Ouch) Normal mice learned to fear the box, but the mutant mice did n’t. They had no memory of being shocked.

The researchers engineered the mutant mice to make a  light-sensitive protein in neurons in the part of the brain that encodes short-term memories. Then they placed the mice back into the box, shining a light onto the animals’ brains to force the modified neurons to fire. This caused the mice to recall the memory of being shocked, and the animals froze — suggesting that the memory had been encoded in the first place. And yet… the next day, the mice had again forgotten their fear of the box.

Next, the scientists pulsed the light, mimicking a process that occurs naturally as a memory is accessed repeatedly over time. This strengthened the connections between the hippocampus and another brain region called the entorhinal cortex, a connection that serves as long-term memory storage. With the memories now firmly embedded, the mice remembered to be afraid of the box, even when the light was off.

Can you get what this means? It means that the memories seemingly obliterated by Alzheimers may not be.

When the team dissected the mouses’ brains, they found that the pulsing stimulation had created new connections between the hippocampus and the entorhinal cortex — connections that are lost as Alzheimer’s disease progresses. Don’t get too excited yet.. the researchers expect that the technique may only work for a few months in mice, or two to three years in humans, before the disease  erases any gains.

This theory about how Alzheimer’s affects the brain agrees with symptoms seen in patients. Our hippocampus appears to be particularly vulnerable to the ravages of Alzheimer’s, so a person with the disease first forgets new memories, like where he left his car. As Alz worsens, more of the brain is destroyed, causing us to forget long-term information such as family members’ names.

Stimulating memories

“It’s a beautifully executed study,” says Itzhak Fried, a neurosurgeon at the University of California Los Angeles. But he cautions that the findings may not translate to human brains, because mice do not develop amyloid plaques in the same way as humans do. And… it’s impossible to test whether the memory-retrieval hypothesis holds true in humans, because researchers haven’t worked out how to stimulate human brains using light.

Ian’s Comment:

Yet another study that tells us that care of the brain is perhaps our most important self-health regimen. My own experience with what looked starkly like early onset Alzheimers came unbidden and -I have to admit – not because I was in any way abusing my brain. I wasn’t taking drugs, drank very moderately.. I was (at that time) vegetarian, so the only possible culprit I can think of is carbs and sugar.

I have learned a great deal since I posted our Coconut Oil Video almost a million views ago. I’ve learned that I am still susceptible. If I go ‘off the rails’ and indulge in either sugar or carbs, it takes only a couple of days before words seem to disappear from my vocabulary and I get ‘foggy’. We use coconut oil in all our cooking so I am still getting plenty, but the carb/sugar effect is clear. I’m also taking H2 every day in water in the form of our I LOVE H2 tablets, mainly because of another study using H2 on Alzheimers.

It appears from the study that H2  that “It is also suggested that the major findings of this study is that hydrogen rich saline was able to improve long-term potentiation, learning, and memory most likely by reducing inflammation and oxidative stress.”

Here’s a video of a discussion between myself and an old friend comparing notes on memory loss, coconut oil and H2. The studies are only mouse studies, but for me, with the constant reminder of memory loss – and possible worse – always close at hand, I’m happy to use everything I can to avert Alzheimers even when it’s only shown to be beneficial in some poor mousies.

If you want more info on H2, Go here for Australia, US, Canada, UK, EU, Gulf


Sources:

  1. Roy, D. S. et al. Nature http://dx.doi.org/10.1038/nature17172 (2016).
    PubMed
  2. Ryan, T. J., Roy, D. S., Pignatelli, M., Arons, A. & Tonegawa, S. Science 348, 10071013(2015).
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  3. Sankar, T. et al. Brain Stim. 8, 645654 (2015).
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