Domestication Process in Addiction: Understanding Addiction from the Evolutionary Perspective

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K22511
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 48:Biomedical structure and function and related fields
• Research Institution: Kyoto University
• Principal Investigator: Goto Yukiori 京都大学, 霊長類研究所, 准教授 (10645584)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: 依存症 / 認知機能 / 情動機能 / 攻撃性 / 意思決定 / ドーパミン / エピゲノム / 前頭前皮質

Outline of Final Research Achievements

This study investigated cognitive, affective, and physiological deficits that characterize behavioral addiction, by conducting a battery of psychological tests and questionnaire surveys, along with physiological assessments, such as prefrontal cortical activity using functional near-infrared spectroscopy, blood monoamine concentrations using HPLC, and whole-genome DNA methylation analysis. We found that patients with behavioral addiction exhibited deficits in probability judgements, associated with attenuated prefrontal cortical activity, and heightened negative affects, such as anxiety, stress, and depression. Moreover, alterations in blood concentrations of monoamines, such as dopamine and serotonin, as well as DNA methylation on the genes associated with synaptic transmission and immune system, were observed in the patients. These results suggest that behavioral addiction may involve deficits of biological systems that are mutual with those with drug addiction.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

近年、ゲーム障害やインターネット依存など、行動嗜癖（行動依存症）に注目が集まっている。しかし、行動嗜癖の概念自体は近年登場した新しいものであり、例えば他の精神障害のカテゴリー強迫性障害との区別も曖昧であり、未だ十分な知見は得られていない。また、行動依存症を特徴づけるような神経メカニズムの知見はなく、これまで研究の進んできた物質に対する依存症との共通点・相違点も明らかになっていない。本研究において、我々は、行動嗜癖の認知機能、情動機能、ならびに生理学的特徴は、薬物依存症と多くが共通することを見出し、行動嗜癖の依存症としての位置づけを発展させた。