Trigger for Learning Discovered

Reported August 11, 2008

ORLANDO, Fla. (Ivanhoe Newswire) -- In a study with surprising results, scientists recently identified a protein necessary for learning.

The protein, called Otx2, works with cells called parvalbumin cells to enable the brain to learn at critical periods of development. Parvalbumin cells are responsible for making connections in the part of the brain that processes visual information. They also receive information from the eye. These cells, in cooperation with the Otx2 proteins, encourage brain plasticity, or the ability to learn.

"There's one cell between the visual input and the actual plasticity, and that's where we made the surprising finding -- that a particular protein used very early in the fetus … is recycled, or reused, in a very specific way after birth to induce a plastic period," senior investigator Takao Hensch, Ph.D., professor of molecular and cellular biology at Harvard University and professor of neurology at Children's Hospital Boston, told Ivanhoe.

This key protein is first responsible for forming the head of a fetus, Dr. Hensch explained.

After studying the function of parvalbumin cells in mice, Dr. Hensch and his colleagues found the Otx2 proteins are sent to these cells by the retina, triggering critical periods of brain plasticity.

Dr. Hensch said developmental disorders like autism are a result of impaired timing of these learning "windows," like the one during which children learn to read. He said he hopes the discovery of this protein will eventually lead to new treatments for disorders like autism, and brain injuries.

"If you have a brain injury in adulthood, it's very hard to recover from that; but if you knew how to switch on the brain plasticity, and basically rejuvenate the brain, then maybe you could accelerate or help out the degree of recovery from injury," he said.

SOURCE: Cell, 2008;134:508-520