A new study by researchers from The University of Texas at Dallas (UT) suggests that the brain's response to nicotine hinges on the smoker's belief about whether or not there is nicotine in the cigarette. Examination of the neural activity of the insular cortex – a part of the brain associated with addiction, drug craving, bodily perception and self-awareness – revealed that in order for smokers to satisfy their cravings, they not only required a cigarette with nicotine in it, but also had to hold the belief that the drug was present. Without this belief, their cravings were not satisfied.
"These results suggest that for drugs to have an effect on a person, he or she needs to believe that the drug is present," says Xiaosi Gu of UT, lead author of the study.
The team used functional magnetic resonance imaging (fMRI) to capture the insular cortex activity of 24 chronic, nicotine-addicted smokers in a double-blind study that took place over four visits. Over this time period, each participant experienced the following four different conditions once each: told "nicotine" and smoked a cigarette with nicotine; told "nicotine" but smoked a non-nicotine cigarette; told "no nicotine" and smoked a non-nicotine cigarette; and told "no nicotine" and smoked a cigarette with nicotine.
"We examined the impact of beliefs about cravings prior to and after smoking while also measuring neural activity," says Gu.
The results revealed a connection between belief and nicotine. Logically, there was a significant decrease in craving when participants smoked a nicotine cigarette and believed that it contained nicotine. However, this effect was not present in those that smoked a nicotine cigarette but believed it was a placebo.
"We expected the presence of nicotine to show some sort of craving response compared to conditions where the subjects did not receive nicotine despite the belief about the nicotine given, but that was not what we found," says Read Montague of of Virginia Tech Carilion and co-author of the study.
The findings suggest that even in deprived smokers, belief can have a powerful effect on addictive psychoactive substances at the behavioral and biological levels, supporting the current data on the subject. Future research could expand on these findings and use them to explore new methods of treating addiction by focusing on the importance of our belief systems and their interactions with brain chemistry.
The findings were published in the journal Frontiers in Psychiatry.
Source: University of Texas at Dallas
