Brain Study Sheds Light on Language Use

VOA News 15/01/2010

A new study on the brain is shedding light on how humans process language. The research, being carried out in San Diego, Boston and New York is helping scientists understand a part of the brain known as Broca's area. The study shows that the brain is more complex than scientists had realized.

This is an X-ray showing electrodes that surgeons use to find and remove the source of seizures (to cure epilepsy), while sparing the source of mental functions like language. In this study, recordings when patients spoke words revealed that one small part of the brain computes the meanings, structure, and sounds of words, separately and in a quick sequence. It is important to note that electrodes are only implanted in people's brains as part of existing and accepted surgical practice. We then get patients' consent to also record from these electrodes for research purposes. Electrodes are never implanted just for research. This image relates to an article that appeared in the October 16, 2009, issue of Science, published by AAAS. The study, by Dr. N.T. Sahin of the University of California, San Diego in La Jolla, Calif., and colleagues, was titled, "Sequential Processing of Lexical, Grammatical, and Phonological Information within Broca's Area."

The medical center at New York University is one of the clinical sites for the study.

Denise Harris, 39, is helping researchers gain a better understanding of the brain. She suffers from epilepsy, and doctors are monitoring her seizures in the hope of performing an operation to minimize them. Her head is bandaged. Wires protruding from the side are attached to electrodes implanted in her brain. Harris says doctors are monitoring her to see whether she is a good candidate for surgery.

"I've been on many medications throughout my life and after a while, they don't work," she said. "I still get seizures. So now, when they remove the part that the seizure is triggered from, it's supposed to stop."

Scientists Use Colored Lights to Program Brain Activity

VOA News 07/01/2010

Scientists in the United States have developed a powerful new method to help calm the abnormal brain activity associated with diseases such as epilepsy and Parkinson's. The technique involves the use of laser light stimulation of special proteins implanted in key areas of the brain.

So-called neural "super silencers," were developed by scientists at Massachusetts Institute of Technology from two genes found in fungi and bacteria. The genes, called Arch (ARK) and Mac, are responsible for making light-sensitive proteins that help the organisms convert light into energy.

But when those genes are inserted into the brain, neurons can be engineered to express the proteins, making it possible to manipulate them with a laser beam and calm irritated nerve cells that are responsible for epilepsy, Parkinson's disease and chronic pain syndromes.

Mouse neuron expressing Arch gene Photo - Image courtesy of Brian Chow, Xue Han and Ed Boyden/MIT

Ed Boyden is a professor of brain and cognitive sciences at MIT. He is the lead author of a study that showed how neurons containing the genes could be turned on and off with pulses of laser-beam light. "If you could turn off those neurons that are behaving inappropriately just for the right amount of time, that allows you to cancel out the aberrant neural dynamics with fewer side effects than if you were to bathe the entire brain in a pharmacological agent," he said.