A research group led by Professor Hidehiko Takahashi of the Graduate School of Medicine, Kyoto University, has found that gambling addicts have difficulty in flexibly switching the amount of risk they can tolerate, and take risks as a result of experiments based on newly devised tasks. It was confirmed that unnecessary risks are taken even under unnecessary conditions.Examination of the patient's brain activity by fMRI also revealed a weak connection between the dorsolateral prefrontal cortex and the medial prefrontal cortex, which are part of the frontal lobe of the brain.
Previous studies have predominantly considered that patients with gambling addiction always prefer risk excessively, tend to have a certain tendency, such as personality, and take fixed risk.However, it was thought that this model was not realistic because people switch the way of taking risks depending on the situation.Therefore, we hypothesized that gambling addiction impairs the ability to switch risk taking depending on the situation.
The study included 21 male patients diagnosed with gambling addiction and 29 healthy males, and devised a gambling task that required switching the optimal risk taking method according to the situation.Since previous studies have revealed brain regions and brain connections related to quota recognition and risk attitude switching in tasks, we investigated brain activity during task execution by fMRI (functional magnetic resonance imaging).As a result, in the case of gambling addicts, the activity of the dorsolateral prefrontal cortex is reduced, and in patients with weaker connections between the dorsolateral prefrontal cortex and the medial prefrontal cortex, the period of gambling is shorter and lower. It was found that there is a strong tendency to select high-risk, high-return gambling based on norm conditions.
By clarifying the neural basis of addiction, it is expected that it will lead to understanding of various pathological conditions of gambling addiction and development of new treatment methods.
Paper information:[Translational Psychiatry] Deficit of state-dependent risk attitude modulation in gambling disorder (English)
