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Yale Researchers Link 'Sticky' Brain Activity to Stronger Cravings

In a recent study, Yale researchers have discovered that individuals with stronger cravings for food or substances exhibit a particular pattern of brain activity. The findings, published in the journal Molecular Psychiatry, suggest that these individuals get "stuck" in certain brain networks.

Communication between regions of the brain is constantly changing. However, traditional neuroimaging technologies often capture only a few minutes of brain activity, missing moment-to-moment changes. Using a more dynamic approach, Yale researchers observed rapid changes in brain activity related to craving.

Jean Ye, lead author and Ph.D. student at Yale School of Medicine (YSM), explained the significance: "But on top of identifying what brain regions are involved in craving, I think how people engage these networks of brain regions over time also has implications." Ye works with Elizabeth Goldfarb and Dustin Scheinost, co-senior authors of the study and faculty members at YSM.

The study included 425 participants with varying health conditions such as alcohol use disorder, cocaine use disorder, prenatal cocaine exposure, or obesity. Participants underwent functional magnetic resonance imaging (fMRI) while viewing neutral images or descriptions of relaxing situations and rated their level of craving on a scale from no craving to very strong craving.

Researchers used machine learning to analyze fMRI images and participants’ craving scores, identifying two networks: one where stronger connectivity predicted stronger craving (positive craving network) and another where stronger connectivity predicted weaker craving (negative craving network). They then applied techniques to detect rapid changes in activity between pairs of brain regions.

Ye noted, "We saw that people who experienced stronger craving spent more time in the network state that is more positively associated with craving." At the same time, these individuals engaged less with the negative craving network state.

The reduced engagement with the negative craving network could be crucial. This network includes brain regions involved in sensory processing and movement initiation. Previous studies have linked crosstalk between these regions to decreased impulsivity and reduced cocaine use. Engaging this network may promote self-regulation and inhibit habit-based behaviors associated with substance use.

Ye emphasized that this imbalance between cognitive stability and flexibility might indicate impaired cognitive control linked to substance use. Additionally, how one engages these networks over time affects experience and behavior. The researchers are now exploring whether similar patterns occur in states like stress or rumination associated with depression.

"For instance," said Ye, "we’d like to know whether people at risk for or diagnosed with depression engage in rumination brain networks more and stay engaged for longer periods than those without depression."

For further inquiries:

Fred Mamoun: fred.mamoun@yale.edu

203-436-2643