Mount Sinai study shows that human beliefs about drugs could have dose-dependent effects on the brain
Mount Sinai researchers have shown that a person’s beliefs related to drugs can influence their own brain activity and behavioral responses in a way comparable to the dose-dependent effects of pharmacology.
The implications of the study, which directly focused on beliefs about nicotine, are profound. They range from elucidating how the neural mechanisms underlying beliefs may play a key role in addiction, to optimizing pharmacological and nonpharmacological treatments by leveraging the power of human beliefs. The study was published in the journal Nature Mental Health.
To explore this dynamic, the Mount Sinai team, led by Ofer Perl, PhD, a postdoctoral fellow in Dr. Xiaosi Gu’s lab when the study was conducted, instructed nicotine-dependent study participants to believe that an electronic cigarette they were about to vape contained either low, medium, or high strengths of nicotine, when in fact the level remained constant. Participants then underwent functional neuroimaging (fMRI) while performing a decision-making task known to engage neural circuits activated by nicotine.
The scientists found that the thalamus, an important binding site for nicotine in the brain, showed a dose-dependent response to the subject’s beliefs about nicotine strength, providing compelling evidence to support the relationship between subjective beliefs and biological substrates in the human brain. This effect was previously thought to apply only to pharmacologic agents. A similar dose-dependent effect of beliefs was also found in the functional connectivity between the thalamus and the ventromedial prefrontal cortex, a brain region that is considered important for decision-making and belief states.
