Bernards Voices

Finding any sort of treatment [for TBI], much less a cure, has not been easy. But some neuroscientists now see great potential in techniques of manipulating the brain’s “neuroplasticity,” its propensity to rearrange its neuronal structure in response to behavior and stimuli.

Earlier this year, the Department of Defense awarded a $2 million grant to Brain Plasticity Inc. to study the effectiveness of Posit Science software in restoring memory and attention in victims of traumatic brain injury, or T.B.I. Posit Science, based in San Francisco, is one of several companies, including Nintendo and Luminosity, that sell brain health software products to consumers.

In Turning to Software to Help Treat Brain Injuries – NYTimes.com, Gordy Slack reports (June 17, 2011) such software could potentially help Traumatic Brain Injury patients and also those who have been determined to have autism, Parkinson’s disease, schizophrenia and other psychiatric and neurological diseases.

“This is the beginning of a revolution,” said Michael Merzenich, the co-founder and chief scientist of Posit Science; the president of Brain Plasticity; and a celebrated University of California, San Francisco, neuroscientist who pioneered the idea of neuroplasticity.

“There is a big gap between the claims and the evidence,” said Dr. Doraiswamy [a Duke University psychiatrist], who said he doubted whether short-term improvements in memory would last longer than the three-month period most studies test.

“If they were a drug,” he said of the software, “they would have been pulled from the market.”

The malfunctioning brain, or what Dr. Merzenich calls the “noisy” brain, is like a radio that, for any number of reasons, is badly tuned to its intended station. The objective of his software, he says, is to clarify a strong signal by repeatedly practicing simple tasks, like recognizing repeated visual patterns.

Theoretically, the brain training software could address both cognitive problems and post-traumatic stress, said Henry Mahncke, Posit Science’s chief executive, a neuroscientist and a former student of Dr. Merzenich.

From May 10th, The New York Times, Alastair Gee reports that “Hazy Recall as a Signal Foretelling Depression”

–in studies under way at Oxford and elsewhere, scientists are looking … to gain new insights into the diagnosis and treatment of depression. They are focusing not on what people remember, but how.

The phenomenon is called overgeneral memory, a tendency to recall past events in a broad, vague manner. “It’s an unsung vulnerability factor for unhelpful reactions when things go wrong in life,” said Mark Williams, the clinical psychologist who has been leading the Oxford studies.

Some forgetting is essential for healthy functioning — “If you’re trying to remember where you parked the car at the supermarket, it would be disastrous if all other times you parked the car at the supermarket came to mind,” said Martin Conway, a cognitive psychologist at the University of Leeds in England. But, a chronic tendency to obliterate details has been linked to longer and more intense episodes of depression.

This is one of my posts, which is just a string of excerpts from the article, but the article is clear, really speaks for itself.

And an unusual paper suggests that overgeneral memory is a risk factor for post-traumatic stress disorder. Scientists at the University of New South Wales in Sydney, Australia, assessed 46 firefighters during their initial training and again four years later, when all had experienced traumatic events like seeing comrades injured or killed. Those who could not recall the past in specific detail during the first assessment were much likelier to have developed the disorder by the later one.

Is overgeneral memory the chicken or the egg? “perhaps overgeneral memory exists in the first place … to block particular traumatic or painful memories.”

Without detailed memories to draw upon, dispelling a black mood can seem impossible. Patients may remember once having felt happy, but cannot recall specific things that contributed to their happiness, like visiting friends or a favorite restaurant.

Some experts think such insights could also be helpful in treating depression. For example, Spanish researchers have reported that aging patients showed fewer symptoms of depression and hopelessness after they practiced techniques for retrieving detailed memories.

Dr. Williams has found that specificity can be increased with training in mindfulness, a form of meditation increasingly popular in combating some types of depression. Subjects are taught to focus on moment-to-moment experiences and to accept their negative thoughts rather than trying to avoid them.

Neurobiologist Eric Kandel shared the 2000 Nobel Prize in Physiology or Medicine for “discoveries concerning signal transduction in the nervous system.” Dr. Kandel studies how neurons in organisms such as sea slugs alter their responsiveness to chemical signals to produce a coordinated change in behavior — work that ties into learning and memory. In this segment, Ira Flatow talks with Dr Kandel about his work and interests.

Clik on Listen button in upper left corner to hear the podcast:

How does memory happen?  At the molecular level …

• short term memory is functional, recorded biochemically
• long term memory is anatomical, new synapses are grown when the memory becomes long term
• how?  genes in the nucleus are turned on, the produce more genes that produce proteins that grow synapses

Kandel also talks about why neurons are more sensitive to oxygen starvation.  Compared to other cells, the cell body of a neuron (which houses the nutritional engine that creates the energy for the cell) is very small compared to its gigantic extensions (axioms and dentrites, which can extend the length of our spine) and thus a neuron is much more vulnerable than other cells to insult to that energy producing engine.

But still a lot left to discover about memory.  What is the frontier now?

• How is it recorded?
• Psychiatric disorders most all involve memory.  Not just alzheimers, but also schizophrenia, depression (at storage problem), PTSD (too much memory, store too well).

Psychiatric illness is a major area of need.  Kandel emphasizes that the meds for schizophrenia haven’t improved since 1960, nor the SSRI meds for depression, since 1980.  And while the SSRIs are effective for certain types of depression, they are not useful for others. We still don’t understand the biological basis, the anatomy nor the genes, involved in mental illness.

And then a lot of anecdotal, reminiscing …  and a very charming laugh.

On NPR’s Science Friday, December 11th, 2009, Ira Flatow interviews Elizabeth Phelps, Professor, Department of Psychology New York University. The podcast is short, only 12 minutes, and it is remarkably clear and informative.

To listen to the podcast, go to http://www.sciencefriday.com/program/archives/200912116, and clik the play button in the upper left hand corner under Listen.

Researchers report a non-invasive, drug-free technique to erase a bad memory in the human brain. Writing this week in the journal Nature, the researchers describe using a behavioral modification technique to remove a simple fear memory in people. The key appears to lie in when the technique is applied. Reactivating a memory, the team found, appears to open a “reconsolidation window,” a time-limited period during which the memory can be changed. We’ll talk with one of the team members about the finding, and how it may aid victims of trauma.

The current conventional talk-therapy for dealing with phobias and Post Traumatic Stress Disorder (PTSD) is called Systematic Desensitization therapy or Extinguishment. This is the old get back up on the horse that threw you therapy. Dr Phelps says that the problem with this therapy is that it creates two memories–the original fear memory and a new one that is safe–and when faced with the stimulus (you see the horse) the two memories compete with each other causing further anxiety and tilting your brain towards choosing the fear memory.

The current consensus of memory is that each time you recall a memory you change it slightly. There is a window of time, called consolidation, where the new, revised memory is processed–tagged, sorted, labeled stored in the right place in the brain. When you recall the fear memory, and then create a new version of that memory during that consolidation window, this research shows that you can replace the original fear memory, instead of creating an extra, competing version of it. (That consolidation window opened, in this study, 10 minutes after recalling the original fear memory.

We can imagine therapies (versus meds) that could be created to do this. This is an example we can understand of how drug-free, non-invasive therapy might work.

Phobias and PTSD involve fear and trauma memories.

At HOP’s (Healthy Outcome Partnership) upcoming Mental Health Week (May 10th – 15th), we will have two or three speakers on PTSD. Listening to this podcast is a nice introduction to potential PTSD therapies.

I highly encourage you to listen to this short podcast.