People with mild cognitive impairment (MCI) who wear a nicotine patch for six months show improvements in attention, memory and mental processing, according to a new study.

MCI involves a decline in mental sharpness that is noticeable, but not severe enough to be classified as dementia, The New York Times reports. Those with the condition often go on to develop more severe disease.

In the new study, 67 men and women with MCI and no other health problems wore a nicotine patch or a placebo patch for six months. The participants, whose average age was 76, did not smoke. They took periodic tests of their mental ability, behavior and mood.

Those who wore a nicotine patch showed improvements in their reaction times, long-term memory and attention, and smaller gains in short-term memory. People who wore a placebo patch showed declines on all of these measures.

Lead author Dr. Paul A. Newhouse of Vanderbilt University said there is evidence nerve cells that regulate attention have nicotine receptors. He pointed out the study was small, and researchers still do not know the effect of nicotine patches on the long-term progression of MCI. He warned against anyone using nicotine patches to try to improve their memory.

The study appears in the journal Neurology.