ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Wednesday, November 20, 1996 TAG: 9611200059
SECTION: NATIONAL/INTERNATIONAL PAGE: A-7 EDITION: METRO
DATELINE: WASHINGTON
SOURCE: Associated Press
Cigarette smoking sharpens short-term learning and memory among young people, but the slight improvement comes at a high risk of heart disease, cancer and a shortened life span, researchers say.
The finding's real value may lie in providing clues about how to treat nicotine addiction, the researchers said Tuesday.
In an effort to pinpoint nicotine's precise effects on the brain, researchers at the University of California, San Diego, tested young smokers and nonsmokers at a word game that required rapid memory and quick recall. Both groups of 12 had electrodes attached to their heads that recorded brain waves.
``It is clear that there was a lot more processing going on in the brains of smokers, when compared to nonsmokers,'' said Jaime Pineda, lead author of a study presented Tuesday at a meeting of the Society for Neuroscience. ``A smoker's brain is busier at the memory task than were the others'.''
Smokers were quicker and more accurate in specifying whether or not a word was part of a set of five words that had been flashed on the screen shortly before. That is a powerful test of working memory.
``Working memory also has been called `scratch pad memory' because it is when the brain only needs to remember things for a short period of time and then wipes it out,'' he said.
The enhanced performance of the smokers was evident even after they abstained from cigarettes for 12 hours, Pineda said.
The researcher, a nonsmoker, emphasized that the slight advantage does not justify the health risks.
``This in no way supports an argument that people should go out and smoke,'' Pineda said.
Despite all the known health effects, scientists are still uncertain about nicotine's precise effects on the brain, Pineda said. Understanding how cigarettes affect the brain may help find ways of breaking the addiction, he said.
Pineda said nicotine from cigarettes appears to mimic a brain chemical called acetylcholine, one of the neurotransmitter molecules that carries messages between brain cells.
When people smoke, Pineda said, the nicotine acts on the same parts of brain cells as acetylocholine and may thus boost brain activity.
Whether that effect continues through a lifetime of smoking, however, is still uncertain.
``All of the people in this study were young, an average of about 21,'' he said. ``We plan to conduct this same test on older smokers to see if the positive effects are maintained. It could well be that the effects are reversed'' and that continued smoking actually diminishes thinking ability.
A spokesman at the University of California, San Diego, said the study was funded entirely by the university and was not supported in any way by tobacco companies.
LENGTH: Medium: 59 linesby CNB