In memory, we understand the process of encoding memory involves a process called long term potentiation (LTP). A neuron signals another connected neuron through the release of neurotransmitters (chemical messengers) that span the gap between neurons called the synapse. As neurons become linked through LTP, one of the ways the receiving neuron can strengthen this connection is by having more receptors sensitive to incoming neurotransmitter messages. One of the problems for translating this LTP mechanism into a model for memory is that these cellular receptors (and just about all of the cellular machinery involved in LTP) are transient. So how can molecular receptors that come and go be used to store memories that last a lifetime?

Work published here by Craddock et.al in the March PLoS Computational Biology provides an intriguing hypothesis that may help to explain how the brain stores persistent, long-term memories. According to this group’s hypothesis microtubules might be the storage medium behind the brain’s capacious memory storage. Microtubules are ubiquitous proteins (assembled from tubulin) into tube shaped networks that makeup the cell’s cytoskeleton. In the PLoS paper, they propose a schemata whereby phosphorylation of microtubules by CaMKII could serve to create storage and logic gates that would enable the brain to store information.

While there are several unknowns presented in the paper, and I at least am cautious to accept taking metaphors too literally, further experimental evidence could bear out that the brain functions very much like a Turing machine.

Northwestern Medicine researchers have made a major discovery that can aid in understanding and treating Alzheimer’s. These researchers have taken human embryonic stem cells and transformed them into basal forebrain cholinergic neurons, those that die in early Alzheimer’s. The technology to grow these neurons in a laboratory will enable drug testing for treatment and also testing to study why these neurons die.

Researchers have demonstrated that these newly formed neurons work just like the originals. They were transplanted into the hippocampus of mice and were shown to function normally. The neurons produced axons to the hippocampus and pumped out acetylcholine, a chemical needed to retrieve memories.

These cells can be grown indefinitely in the lab, allowing for heavy amounts of research into these cells, something that’s never been done before. Perhaps now, with these new cells, we can be one step closer to understanding and treating this disease.

It is important to remember that savantism is not autism, although it very often occurs with severe forms of autism, what really is key to the condition is memory. Mr. Peek could read a book in a fraction of the time it would take a normal person. He would read the left page with his left eye and the right page with his right eye; and whatever he read, he remembered. Some savants can memorize digits to thousands, or tens-of-thousands of decimal places, play complex music after one hearing, or recreate images or scenery of vast complexity from a glimpse. What underlies all of these abilities is a fantastic memory. Will we ever understand, how Kim Peek, the most brilliant memory documented by science worked? Many are trying to figure out this neurological puzzle.

One of the clues to Mr. Peek’s inner workings might lie not in the gain of some abilities, but instead in the loss of ability. According to the Wisconsin Medical Society, “He had an enlarged head, with an encephalocele, according to his doctors. An MRI shows, again according to his doctors, an absent corpus callosum — the connecting tissue between the left and right hemispheres; no anterior commissure and damage to the cerebellum.” Some neuroscientists have argued that these missing structures allowed his brain to work in its own unique way, and that what really was different about Mr. Peek was not that he could remember, but that he could recall, and in fact not forget what he had learned.

What would it be like to have at least some of these abilities? What I think all savants show us is that there is some untapped potential within all of us, a potential that we somehow are unable to access. We also see that these abilities seem to come at a high price of diminished social or physical functioning. Will there be a time when we can access these abilities, when we understand more about the brain? Would these abilities be as valuable as they appear to be? I guess we will have to answer that question if any when we get there.

Great info and Videos on Kim Peek:

http://www.wisconsinmedicalsociety.org/savant_syndrome/savant_profiles/kim_peek