He says they might be trying to increase their dopamine levels to make up for the deficits in their reward system.

VOA: special.2009.09.16

Yet,every day,Americans depend on their transportation system to keep them, and the largest economy in the world, on the move.

VOA: special.2010.01.11

He says they might be attempting to increase their dopamine levels to make up for the deficits in their reward system.

VOA: special.2009.09.29

Their central nervous system may tell the brain that there is pain even when there is no cause for the pain.

VOA: special.2011.07.26

They are making their way up a system built years ago to link the Mississippi to Lake Michigan.

VOA: special.2009.12.15

And the answer,she says, is that bilingual people are often better at controlling their attention -- a function called the executive control system.

VOA: special.2011.03.09

He plans to work to improve the legal system so that competing groups can settle their differences in court instead of the battlefield.

VOA: special.2009.01.28

It had been the first time people moved beyond their small planet into the huge solar system.

VOA: special.2009.07.29

"The criminal justice system relies on the testimony of persons and their ability to tell the truth.

VOA: special.2009.08.31

Researchers at the University of Toronto in Canada are studying a mobile phone system that may help people with diabetes control their blood pressure.

VOA: special.2010.12.06

Google agreed to create a system to pay copyright holders when their works are used online.

VOA: special.2011.04.01

In California, voters passed a measure to replace their primary election system, starting next year.

VOA: special.2010.06.12

But the researchers say their holographic telepresence system is still years away from completion.

VOA: special.2010.11.15

Workers in an office are afraid to try to use their new computer system.

VOA: special.2010.06.27

Of course,with signers,their first language has no written system at all, just hand gestures.

VOA: special.2011.04.13