Resisting food temptation: how do affective and cognitive brain systems interact?

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PROJECT SUMMARY/ABSTRACT The brain's reward system can promote survival by incentivizing adaptive behaviors such as eating, or it can undermine survival by incentivizing maladaptive behaviors such as compulsive drug use or excessive eating. Results from animal models indicate that reward-seeking behaviors such as eating and substance use are regulated by two systems: an affective system, which automatically allocates attention to reward-related cues, and a cognitive system, which enables top-down allocation of attention (Pitchers et al., 2018). Animals with an overreactive affective system are prone to compulsive cue-induced eating and cue-induced drug self- administration, whereas animals with a strong cognitive system are often able to resist these behaviors (Tunstall & Kearns, 2015). Much like these preclinical results, our results showed that humans with enhanced affective responses to reward-related cues are more likely to be obese (Versace et al., 2016), are more vulnerable to cue- induced eating (Versace et al., 2018), and are more vulnerable to smoking relapse (Versace et al., 2012) than individuals who are not highly cue-reactive (non-cue-reactive individuals). While our results demonstrate that an overreactive affective system confers vulnerability to many maladaptive, cue-induced behaviors, these results are silent about the role that the brain's cognitive system plays in mitigating this vulnerability. The proposed research aims to address the following gap in knowledge: are cue-reactive individuals also burdened by an impaired cognitive control system, or do they have an efficient cognitive control system that is overwhelmed in the presence of enhanced incentive responses to cues? My central hypothesis is that cue-reactive individuals do not have a general deficit in cognitive control, but rather their enhanced cue-induced incentive responses overwhelm their cognitive control system. I will test this hypothesis with the following specific aims: 1) Determine the extent to which cognitive control differs between cue-reactive and non-cue-reactive individuals while they engage affective and cognitive brain systems; 2) Integrate measures of cognitive control into predictive models of cue-induced behavior. I will test aim 1 by monitoring the engagement of cognitive control using power in the EEG theta frequency band—a validated measure of cognitive control—while human subjects complete a cued food delivery task and a flanker task. To achieve aim 2, I will incorporate psychophysiological measures of cognitive control into our predictive models of cue-induced behavior which previously relied on affective measures only. This research is significant because it will identify not only the mechanisms that make some individuals vulnerable to cue-induced, addictive behaviors, but also the mechanisms that make others resilient. Furthermore, this fellowship will provide me with the necessary training to become an impactful independent researcher in the neuroscience of addiction.