In a recent study published in Translational Psychiatry, researchers discovered distinct patterns in how brain regions communicate in individuals with alcohol use disorder compared to healthy individuals. Using advanced imaging and analytical techniques, the study found altered connections in specific brain areas related to self-control, decision-making, and reward processing. These changes, they suggest, could explain why some people develop alcohol use disorder and struggle to control their alcohol intake.
The study aimed to clarify how different parts of the brain interact in alcohol use disorder. Alcohol misuse is a widespread public health issue, causing significant health and social challenges. While past studies have explored brain function in individuals with alcohol use disorder, the exact patterns of connectivity between specific brain areas remain unclear. This study focused on identifying the unique brain connectivity patterns associated with alcohol use disorder, hoping to improve diagnosis and treatment.
“Our laboratory has extensively researched addiction, aiming to elucidate the neural mechanisms underlying addiction and identify key biomarkers for effective treatment interventions,” said study author Xiaochu Zhang, a professor at the University of Science and Technology of China.
“Additionally, we have been actively involved in developing innovative therapeutic approaches for addiction management, including neurofeedback and transcranial electrical stimulation techniques. Alcohol use disorder is a significant addiction that imposes a substantial economic burden on families and society, while its treatment remains challenging. The identification of key neurobiomarkers in the management of alcohol addiction can offer crucial insights for more effective interventions. Our project is conducted within this framework.”
To investigate this, researchers examined two groups: 30 men with alcohol use disorder and 32 healthy men. Each participant underwent resting-state functional MRI, a type of brain scan that measures connectivity between different brain regions while the person is at rest. The study used a method called multivariate pattern analysis, which involves machine learning to distinguish individuals with alcohol use disorder from healthy individuals based on brain activity patterns.
By looking at the direction and strength of connections between regions, they aimed to identify patterns unique to alcohol use disorder. They focused on specific brain areas that past research suggested were involved in self-control, decision-making, and reward processing, including the pre-supplementary motor area, anterior cingulate cortex, lateral orbitofrontal cortex, putamen, and nucleus accumbens.
The findings revealed distinct connectivity patterns in individuals with alcohol use disorder, especially in the pre-supplementary motor area, anterior cingulate cortex, putamen, and nucleus accumbens. These areas showed altered connectivity that, the researchers suggest, might contribute to the difficulties in self-control and heightened impulsivity seen in individuals with alcohol use disorder.
Importantly, they found that the connection between the anterior cingulate cortex and putamen, as well as between the nucleus accumbens and pre-supplementary motor area, were linked to the severity of alcohol dependence. Individuals with more severe alcohol use disorder symptoms showed stronger or weaker connections in these areas, depending on the specific brain pathway. The analysis accurately distinguished between participants with alcohol use disorder and healthy individuals, suggesting that these connectivity patterns could be used as potential markers for diagnosing alcohol use disorder.
“Our findings revealed atypical causal connectivity between cortical and subcortical brain regions in patients diagnosed with alcohol use disorder,” Zhang told PsyPost. “Furthermore, these atypical causal brain connections contribute to the correlation observed between addiction severity and behavioral measures. These findings suggest that impulsivity may serve as a significant personality trait predisposing individuals to alcohol consumption and the development of alcohol use disorder, thereby providing crucial insights for early prevention and diagnosis.”
“Moreover, in future studies focusing on withdrawal and relapse prevention in patients with alcohol use disorders, medical professionals or researchers could consider integrating traditional drug therapy with innovative interventions (such as transcranial electrical stimulation) to gain valuable insights into enhancing rehabilitation outcomes by ameliorating aberrant causal connectivity between cortical-subcortical brain regions.”
However, there are some limitations to consider. The study focused only on men, as male participants were more readily available in treatment settings, so the results may not apply to women with alcohol use disorder. Future research should include a more diverse sample. Additionally, many participants with alcohol use disorder also used nicotine, which could influence the brain’s connectivity patterns. While the researchers attempted to account for this, future studies could benefit from more rigorous control over smoking habits. They also suggest that examining larger brain networks and incorporating additional imaging techniques could deepen understanding of how alcohol use disorder affects the brain’s overall connectivity.
The study, “Atypical effective connectivity from the frontal cortex to striatum in alcohol use disorder,” was authored by Hongwen Song, Ping Yang, Xinyue Zhang, Rui Tao, Lin Zuo, Weili Liu, Jiaxin Fu, Zhuo Kong, Rui Tang, Siyu Wu, Liangjun Pang, and Xiaochu Zhang.
