Nicotine Helps Schizophrenics with Attention and Memory
Cigarette smoking may improve attention and short–term memory in persons with schizophrenia by stimulating nicotine receptors in the brain, according to a study by Yale School of Medicine researchers in the June issue of The Archives of General Psychiatry.
Persons with schizophrenia smoke two to three times more than smokers without mental illness, said the researchers. They found that when study subjects with schizophrenia stopped smoking, attention and short–term memory were more impaired, but, when they started smoking again, their cognitive function improved. No effects from stopping or resuming smoking were observed in smokers without mental illness.
Participants with and without schizophrenia were then asked to smoke while taking a drug called mecamylamine, which blocks nicotinic acetylcholine receptors in the brain, preventing the nicotine from acting on those receptors. Mecamylamine blocked the ability of smoking to improve cognitive deficits in schizophrenia, but not in persons without mental illness. The findings suggest that when people with schizophrenia smoke, they may in part be self–medicating with nicotine to remedy cognitive deficits.
“Our findings have significant implications for developing treatments for cognitive deficits and nicotine addiction in schizophrenia,” said Kristi Sacco, associate research scientist in the Department of Psychiatry and first author of the study. She said the results may also help explain the high rates of smoking in people with schizophrenia. She added that this study does not suggest that people with schizophrenia who do not smoke should start smoking.
Tony George, M.D., associate professor in the Department of Psychiatry, is senior author of the study.
The study was funded by grants from The National Institute on Drug Abuse and the National Alliance for Research on Schizophrenia and Depression. The researchers are members of the Transdisciplinary Tobacco Use Research Center at Yale and the Program for Research in Smokers with Mental Illness. For more information about both projects please see www.quitwithyale.org and www.prism.yale.edu.