VOA慢速英语2014 一种电刺激而非药物可以帮助治疗大脑疾病（在线收听）

Electric Shocks, Not Drugs, Help A Brain Disease 一种电刺激而非药物可以帮助治疗大脑疾病

From VOA Learning English this is the Health Report.

Modern medicine mainly uses drugs to cure disease.  But what if drugs were replaced with electricity?  Pacemakers, small machines that doctors surgically place in the body, already use electric signals to help weak hearts beat right.

And now, scientists are using electricity on the brain to ease the effects of Parkinson's disease.  Parkinson's disease causes uncontrollable shaking, or tremors.

Simply walking down the street is a great gift for David Dewsnap.

The usual drug treatment did not help his Parkinson's disease.  So, doctors cut open his skull and placed wires, or electrodes, deep in his brain.

The Deep Brain Stimulation System is a two part medical device.  One part is thin wires that doctors place in the part of the brain connected with movement.  The other part is a battery pack. The battery produces the electric signals.

Before doctors wired his brain, Mr. Dewsnap could not even take a short walk.

DAVID DEWSNAP: "This procedure has been just amazing for me.  Without seeing me before, you don't really understand what it was like. I couldn't use ... the left side of my body. I couldn't (could not) use it really."

Caleb Kemere is an electrical engineer and brain scientist at Rice University.  He has been using brain stimulation in his experiments on rats.

He knows this treatment works.  What he doesn’t know is how.

CALEB KEMERE: "We are probably making it work not as it is supposed to work, but in a new way that allows for movements to happen faithfully or for a tremor to go away."

Mr. Kemere says the small electric shocks may trick the brain. The shocks copy the work of a brain chemical called dopamine.  Dopamine helps control movement – or motor activity.

Mr. Kemere wants to develop a brain stimulation system to treat other disorders.  He explains that the system would process signals coming from the brain in real-time and then use those signals to control its own electrical output.

CALEB KEMERE: "We propose to take this and then expand into something that has a much more complicated processor like the one that is found in your cell phone that can process incoming signals that we actually would be getting from the brain in real time, understand what’s (what is) going on and then modulate the brain stimulation in response to that."

Mr. Kemere says first researchers need to settle some small problems such as what electrical signal to use.

CALEB KEMERE: “We don’t what signal to use and we don’t know how to do that modulation.”

The National Science Foundation gave Caleb Kemere money to work on such research.  He believes there could be experimental devices that help people suffering from other mental disorders within five years.