Internet gaming disorder: Microstructural brain alterations and their relation to functionally assessed correlates of reward processing, inhibitory control and the self-concept

在过去的10年里，网络游戏障碍的病例数量不断增加，使这种疾病日益成为临床研究的焦点。然而，仍然缺乏适当的治疗和预防措施，特别是针对青少年的治疗和预防措施。鉴于这种情况的高成瘾性，本提案侧重于在线角色扮演游戏的问题使用。这些游戏提供了多个用户通过他们的图像代理（角色）在虚拟世界中相互合作或对抗的同时游戏。与物质成瘾和病理性赌博的相似之处指向中皮质边缘奖励处理以及前额叶抑制控制机制的改变。扩散张量成像（Diffusion Tensor Imaging， DTI）研究表明，皮层下区域（如边缘奖励系统纹状体）的相对早熟与前额叶控制区成熟过程的延迟之间存在不平衡，这是青少年成瘾障碍易损性增加的基础。奖励相关脑区的早期成熟可能导致对即时奖励的渴望和冒险行为的增加，由于其发育迟缓，前额叶抑制控制机制无法抵消这种渴望。鉴于年轻人受影响的比例很高，这个解释模型可能对网络游戏障碍也很重要。对网络游戏成瘾者的奖励处理研究表明，在感知虚拟世界和虚拟世界相关图像时，纹状体大脑激活增加。这些线索的高度显著性可能是基于通过增加对自己化身的认同来补偿经常观察到的自我概念缺陷。与自我概念相关的功能性磁共振成像（fMRI）研究表明，这涉及到一个额顶叶网络，例如由内侧前额叶皮层（MPFC）和顶叶包括角回（AG）组成。相应的青少年DTI研究显示，与年龄相关的白质成熟过程发生在连接大脑额顶叶区域的上纵束。我们自己的研究小组对网络游戏成瘾者进行的一项研究表明，与身体相关的自我概念缺陷与AG活性降低有关。相反，AG过度激活与对自己化身的认同程度呈正相关。结合之前的研究结果，本研究旨在纵向评估男性青少年和年轻成人网络游戏成瘾者的奖励加工、抑制控制和自我概念方面的微观结构（DTI）和功能（fMRI）测量之间的关系。

Accumulating case numbers of internet gaming disorder have moved the condition increasingly into the focus of clinical research within the past 10 years. Yet, adequate therapies and preventive measures, especially for adolescents, are still lacking. Given the high addictive potential of the condition, this proposal focuses on problematic usage of online role-playing games. These offer the simultaneous gaming of multiple users via their graphical agent (avatar) with or against each other in a virtual world. Similarities to substance addictions and pathological gambling point towards alterations in mesocorticolimbic reward processing- as well as prefrontal inhibitory control mechanisms. Diffusion Tensor Imaging (DTI) studies suggest an imbalance between the relatively early maturation of subcortical areas such as the striatum of the limbic reward system and retarded maturation processes in prefrontal control areas to be at the basis of adolescents increased vulnerability for addictive disorders. The early maturation of reward-associated brain regions might entail craving for immediate rewards and increase risk-taking, which cannot be counterbalanced by prefrontal inhibitory control mechanisms due to their delayed development. Seeing the high prevalence of young affected individuals, this explanatory model might also become essential for internet gaming disorder. Reward processing studies on internet gaming addicts showed increased striatal brain activations upon the perception of avatar- and virtual world-related images. The high salience of these cues might have its basis in the compensation of often observed self-concept deficits by an increased identification with the own avatar. Self-concept-related functional Magnetic Resonance Imaging (fMRI) studies suggest the involvement of a fronto-parietal network, e.g. composed of the medial prefrontal cortex (MPFC) as well as the parietal lobe including the Angular Gyrus (AG). Corresponding DTI studies on adolescents showed age-related white matter maturation processes in the superior longitudinal fasciculus, connecting fronto-parietal brain regions. A study of our own research group on online gaming addicts indicated an association of body-related self-concept deficits with AG hypoactivations. In contrast, AG hyperactivations positively correlated with the strength of identification with the own avatar. Connecting to previous research results, the present proposal aims to longitudinally assess the relation between microstructural (DTI) and functional (fMRI) measures investigating reward processing, inhibitory control as well as self-concept aspects in male adolescent and young adult internet gaming addicts.