MAY 29, 2015 9:17 AM PDT

Good News for Alzheimer's and TBI: Light Activates Memories Lost to Amnesia

WRITTEN BY: Will Hector
One of the bigger questions in the field of neuroscience has been whether the amnesia that results from Alzheimer's or traumatic brain injury is caused by damage to brain cells storing memories or by damage to the mechanisms of memory retrieval.

Either way, memory loss is a frightening prospect since it's a major component to one's identity. Luckily, answering the question-and potentially solving the problem of memory loss-just got a lot easier. A groundbreaking paper provides strong evidence pointing to damaged memory retrieval mechanisms as the culprit in this type of retrograde memory loss.
Optogenetics procedures use light to activate the memory retreival mechanism in the brain.
Memory is a tricky thing conceptually, as anyone who's ever discovered that details of a shared memory don't match those of a friend or family member can attest. Neurologically it gets even trickier. That's why this discovery offers so much potential.

Susumu Tonegawa, who directed the research from his post as the Picower Professor in MIT's Department of Biology and director of the RIKEN-MIT Center at the Picower Institute for Learning and Memory, summed up the findings succinctly: "Amnesia is a problem of retrieval impairment."

Prior to the discovery by MIT researchers, the prevailing theory on memory has been that during the process of having a memory, physical or chemical changes activate a network of neurons known as memory engram cells. If these cells get activated, for example by an odor or a photograph, a constellation of neurons responds to provide a particular memory.

The paper, published in the journal Science, describes how researchers used a light technology called optogenetics to restore memories that were irretrievable prior to the treatment. The process involved adding proteins-which could be activated with light-to the relevant neurons in the hippocampus.

The researchers then used the optogenetic process to activate memory engram cells, which in turn were able to express a memory. But the experiment also showed the synapses connecting these cells had been strengthened by the process, or in Tonegawa's words, had "undergone this augmentation of synaptic strength."

The researchers had used anisomycin to block the synapses from strengthening-essentially blocking memory-before recovering memory function using the optogenetic procedure.

"If you test memory recall with natural recall triggers in an anisomycin-treated animal, it will be amnesiac, you cannot induce memory recall," Tonegawa reported. "But if you go directly to the putative engram-bearing cells and activate them with light, you can restore the memory, despite the fact that there has been no LTP."

LTP stands for long-term potentiation and describes what happens when, through learning and experience, synapses are strengthened and connectivity between neuron groups becomes enhanced.

Follow Will Hector on Twitter: @WriterWithHeart

(Source: Science Daily)
About the Author
  • Will Hector practices psychotherapy at Heart in Balance Counseling Center in Oakland, California. He has substantial training in Attachment Theory, Hakomi Body-Centered Psychotherapy, Psycho-Physical Therapy, and Formative Psychology. To learn more about his practice, click here: http://www.heartinbalancetherapy.com/will-hector.html
You May Also Like
NOV 07, 2019
Neuroscience
NOV 07, 2019
Reading, Hearing Language Connects Meaning to Same Region in the Brain
Scientists at the University of California Berkeley used improved functional MRI resolution to show that similar neural circuits in the same regions of the...
NOV 11, 2019
Neuroscience
NOV 11, 2019
The Women Who Can Smell Without Olfactory Bulbs
Until now, it has been commonly accepted that our sense of smell depends on the transmission of olfactory information from the nose to the olfactory bulb i...
DEC 04, 2019
Neuroscience
DEC 04, 2019
Antibiotic Usage May Cause Parkinson's, Study Finds
A study from Helsinki University Hospital, Finland suggests that excessive usage of certain antibiotics may increase one’s risk of developing Parkins...
DEC 20, 2019
Neuroscience
DEC 20, 2019
Does Having Herpes Increase Your Risk for Alzheimer's?
Around 44 million people around the world have Alzheimer’s disease, a progressive form of dementia that leads to memory loss and a decline in cogniti...
FEB 03, 2020
Cell & Molecular Biology
FEB 03, 2020
Brain Organoids May Not be Living Up to the Hype
Cells can be grown in special ways to create three-dimensional, miniature models of organs. But how good are they?...
FEB 12, 2020
Cannabis Sciences
FEB 12, 2020
Smoking Marijuana Leads to False Memory Formation
Smoking marijuana is known to make people forgetful. Now however, research has shown that smoking the substance may also make people remember things that n...
Loading Comments...