Nicotine is a very commonly used drug. As we know, drugs can alter our brain states and brain areas after continuous use. This study focuses on different brain states (activity of the brain) and how nicotine affects them. One brain state is DMN which stands for the default mode network. This network of interacting brain regions is active typically when one is awake, but not focused on anything specifically, a wakeful rest in other words. Other brain states include SN, which is the salience network, this network is involved with feelings associated with rewards and is one of the most commonly activated. The third one that this study mentions is the CEN which stands for central executive network. The CEN manipulates information, is responsible for decision making, problem solving, etc. This study will be measuring the activity of these brain states with the use of fMRI’s, this technique stands for functional magnetic resonance imaging. It is done by basically using magnets to capture images of the brain that show which parts of the brain are functioning during different tasks. During these scans, our brains are moving between different states, staying in one for an amount of time before we transition out of that brain state and enter into another.

Previous studies have stated that nicotine-dependent individuals spending more time in DMN state at rest, positively predicts greater brain reactivity to smoking cues and therefore a rise in cue-induced cravings. The current study wants to focus on whether or not nicotine has a strong impact on resting-state network dynamics in non-smoking individuals. To test this, 17 healthy non-smokers participated in the study where they were either given a nicotine lozenge or a placebo, their resting state data was then collected with use of the fMRI.

The results of this study found that while nicotine did not seem to have much of an effect on the CEN, acute nicotine administration in these healthy non-smokers significantly increased their time spent in SN state and decreased their time spent in DMN state at rest. Simply, nicotine reduced DMN and enhanced SN function. This is similar with what we find in chronic smokers, in that nicotine reduced activity in key DMN regions during both resting state as well as during attention demanding tasks (Wang et al., 2021). Overall, this study shows how just an initial, acute dose of nicotine in non-smokers gives the same results when it comes to brain states as chronic smokers. This can impact our cognition in a way that may lead to continuous nicotine use as it may be reflected with the increase in activity of the salience network.

Reference:

Wang, K. S., Brown, K., Frederick, B. B., Moran, L. V., Olson, D., Pizzagalli, D. A., Kaiser, R. H., & Janes, A. C. (2021). Nicotine acutely alters temporal properties of resting brain states. Drug and Alcohol Dependence, 226. https://doi-org.cbu.idm.oclc.org/10.1016/j.drugalcdep.2021.108846