Xiaosi Gu, University of Texas at Dallas – Effects of Belief on Nicotine Cravings

Is your brain to blame for your nicotine craving?

Xiaosi Gu, Assistant Professor at the School of Behavioral and Brain Sciences at the University of Texas at Dallas, explores this question.

In 2015, Dr. Xiaosi Gu established the Computational Psychiatry Unit at the Center for BrainHealth, part of The University of Texas at Dallas where she is also an assistant professor in the School of Behavioral and Brain Sciences.

Dr. Gu’s research in computational psychiatry examines the neural and computational mechanisms underlying human decision-making and social interaction in both health and disease, through a synthesis of functional magnetic resonance imaging (fMRI), brain connectivity modelling, neuropsychology (brain lesions studies), pharmacological challenges, and computational modelling.

The goal of her research program is two-fold: 1) to help re-define and eventually improve human mental health; 2) to understand the neural and computational mechanisms of decision-making and social behavior. She uses a highly inter-disciplinary approach in her research, which involves the integration of theories and methods from cognitive neuroscience, behavioral economics, psychology, psychiatry, mathematics, biophysics, computer science, and more.

Dr. Xiaosi Gu started her neuroimaging research at the Department of Psychology at Peking University (PKU), Beijing. After receiving a dual degree in Psychology and Economics from PKU, she moved to New York City to pursue a Ph.D. in Neuroscience at the Mount Sinai School of Medicine.  Dr. Gu completed her postdoctoral training in computational psychiatry and decision neuroscience at the Wellcome Trust Centre for Neuroimaging at University College London (UCL). During her time in London, she set up the world’s first computational psychiatry course at UCL.

Effects of Belief on Nicotine Cravings

How much of a nicotine craving is only in your head? Our research shows that it is a lot more than we thought. My colleagues and I found that in order to satisfy a nicotine craving, smokers had to not only smoke a nicotine cigarette, but also believe that they were smoking nicotine.

In a recent study, we examined the impact of beliefs on cravings before and after smoking while measuring neural activity in the insula cortex, a region of the brain that plays a role in diverse functions such as bodily perception and self-awareness. The insula cortex is also associated with drug cravings.

Twenty-four nicotine-addicted smokers participated in the double-blind fMRI study. Over four visits, participants were twice given a nicotine-containing cigarette and twice a placebo. With each type of cigarette, they were once accurately told they received nicotine and once told no nicotine.

We expected the presence of nicotine to show some sort of craving response in the brain compared to conditions where individuals did not receive nicotine, but that was not what we found.

The fMRI scans showed significant neural activity that correlated to both craving and learning signals when participants smoked a nicotine cigarette and believed its nicotine content was genuine. However, smoking nicotine, but believing it was a placebo, did not produce the same brain signals.

These findings drastically contrast with conventional neuroscience ideas about nicotine that focus on the molecular level. We were able to see a ‘top down’ effect that suggests belief has a much greater role in nicotine addiction than we previously recognized. Better understanding this can help open up new avenues of addiction treatment.