Long-term smoking can affect the brain by making its cortex thinner, claims a new study.
The study led by McGill University additionally found that stopping smoking helps to restore at least part of the cortex's thickness.
The team of researchers explained that cortex was the outer layer of the brain in which critical cognitive functions such as memory, language and perception take place.
Dr. Sherif Karama, lead author and assistant professor of psychiatry at McGill University said that current and ex-smokers with average age of 73 had many areas of thinner brain cortex than those that never smoked, whereas the ones who stopped smoking seemed to be partially recovered with the cortical thickness for each year without smoking.
The study suggested that recovery was slow, as heavy ex-smokers in the study who had given up smoking for more than 25 years still had a thinner cortex.
The researchers further added that the cortex grows thinner with normal aging, but smoking appears to accelerate the thinning process, and a thinner brain cortex was associated with adult cognitive decline.
Dr. Karama added that smokers should be informed that cigarettes could hasten the thinning of the brain's cortex, which could lead to cognitive deterioration.