Seeing this paper is bittersweet for me as I work in a memory neuroscience lab that's been working on essentially the same question for a number of years. These guys beat us to the headline :(
That said, it is a great accomplishment for the field. Less so for the prospect of 'memory-restoring' technology in the near future, but more for what it says about how memory works. Essentially, this paper (and our work hopefully coming soon), proves that retrieval cues are the most superficial aspect of the brain's systems for memory. Thus, they fall first to the ravages of Alzheimer's and when they're gone, the pattern of information is still there, but the brain is unable to recall that specific memory when input into the network is noisy. There's been some other papers recently showing the persistence of memories even when synapses and spines are lost (for example, during hibernation). It's as if a record of learning is also stored somewhere in the cell's genes, but no one seems to really know what to make of it.
Maybe that stuff will also be of interest to neural network people...
All that said, there's now a large-scale study getting started in Canada that will be stimulating the brains of MCI and AD patients with tDCS to slow down Alzheimer's (pACT-MD). Maybe they'll be able to recover some those lost memories!
I find it really interesting how often neuro-science reminds me of work. This apparently means that the brain has some kind of equivalent to a partitioning table of a hard drive, and if that's botched, it becomes hard to find the data on the disk again. It's still there, but good luck figuring out where the file starts.
And how far still from editing bad experiences out from memory, replacing them with pleasant ones that never happened, and freely moving that memory across customized bodies?
Given what we think we know about how memory works, we're probably much closer to editing out bad memories than we are to copying memories across bodies.
I say that because there does not seem to be a non-interactive way to recall memories. Every time a person experiences a memory (remembers), they also alter that memory. Researchers have been able to fairly easily alter or implant memories simply by suggesting the changes to subjects while they are in the process of remembering.
It sort of makes sense--the moment of remembering is itself a memorable moment, and so the brain updates or replaces the original memory with what was recalled the most recent time. If the recall was messy, the old memory will now be messy too.
Thanks for commenting, in any case, from a position of expertise!
Just curious, in such experiments, how does the 'blue light' reach interior cells? Is it simply of such intensity, from an external source, that it penetrates deeply through tissue into the mice skulls? (A bit like a flashlight-through-a-hand?)
Or, is the light source somehow inserted to be close to the cells (even under the skull)?
Not an expert; what I think jdpigeon is referring to, though, is that the information storage is just fine, even if the indexing mechanisms aren't.
Like recovering data from a broken filesystem - the directory structure is lost and for a normal usecase the data might as well be gone, but a lot of the content is theoretically there and recoverable if some indexing system (even one different from the original) can be created.
Yes! It hasn't been demonstrated in mammals, but in the elife paper linked above, I think they saw synapses regrowing in the same positions. However, its not clear if it's actually necessary for them to be in the same position.
I'm a medical student and had to conduct several simple short-term memory tests (Mini Mental State Examinations, or MMSEs for short) today. It's quite upsetting for the patient when they don't even know how to spell 'world' backwards, or can't recall the words "ball car man" that you told them half a minute earlier. I wonder if this concept will improve both long term and short term memory, or just the latter?
The article says:
Doug Brown, director of research at the Alzheimer’s Society, cautioned that the technique is not something that can be translated into a procedure that is safe for the estimated 44 million people worldwide with dementia just yet.
which makes clear that the blue light technology is very far from being a cure for Alzheimer.
On the other hand, Dr Dale Bredesen has already in a very small study with 10 persons, reversed Alzheimer in 9 of 10 patients. A followup study with 100 persons is not yet finished but preliminary results show "similar results".
The work of Dr Bredesen is mostly unknown but this will likely change in the near future. The work of Dr Bredesen may start a revolution since he does not use a traditional medicine but a holistic approach which basically fights inflammations at all levels possible.
I did some digging into Dr. Bredesen's work and the study you mentioned didn't have a control group. If you don't have a control group and you're changing dozens of variables simultaneously, you're not doing science.
This is not to say that his patients don't enjoy some subjective benefits, or that diet and exercise and mental stimulation aren't helpful, but Dr. Bredesen cannot have any scientific insight into Alzheimer's until he does an actual study.
That said, it is a great accomplishment for the field. Less so for the prospect of 'memory-restoring' technology in the near future, but more for what it says about how memory works. Essentially, this paper (and our work hopefully coming soon), proves that retrieval cues are the most superficial aspect of the brain's systems for memory. Thus, they fall first to the ravages of Alzheimer's and when they're gone, the pattern of information is still there, but the brain is unable to recall that specific memory when input into the network is noisy. There's been some other papers recently showing the persistence of memories even when synapses and spines are lost (for example, during hibernation). It's as if a record of learning is also stored somewhere in the cell's genes, but no one seems to really know what to make of it.
Maybe that stuff will also be of interest to neural network people...
All that said, there's now a large-scale study getting started in Canada that will be stimulating the brains of MCI and AD patients with tDCS to slow down Alzheimer's (pACT-MD). Maybe they'll be able to recover some those lost memories!