认知与发展心理学研究室知识库

吸烟成瘾和网络游戏成瘾是两种最常见的成瘾形式。在DSM-5中，吸烟是一种“烟草使用依赖”类别下的物质成瘾，被定义为长期使用烟草，具有物质成瘾的典型症状，如渴求、耐受、戒断、难以戒除以及由于持续吸烟而导致的社会、职业和个人生活障碍。而网络游戏成瘾是一个新的健康问题，在DSM-5中被归类为“网络游戏依赖”，其定义是对网络游戏的专注和痴迷，而这些游戏会妨碍社会、个人或职业生活。网络成瘾也具有典型的依赖症状，如耐受、戒断和难以戒除。它被列入DSM-5中“有待进一步研究的情况”，需要更多的研究。两种成瘾都具有情绪失调、易冲动、应对能力差、抑郁焦虑风险高、奖赏加工和认知控制能力差等特点。双系统模型认为，成瘾是由于奖赏系统和认知控制系统之间的失衡导致的。但是，对于以吸烟为代表的物质成瘾和以网络游戏成瘾为代表的行为成瘾之间是否有不同的机制，还有待研究。本研究旨在利用双系统模型，探讨吸烟成瘾和网络游戏成瘾的奖赏加工和认知控制的一般性和特异性的行为和神经模式。

以往的研究主要集中在物质成瘾与行为成瘾之间的共性。然而，在行为成瘾者和物质成瘾者之间，还没有研究探索出共同的和独特的奖励处理和认知控制机制。本研究旨在通过比较和对比行为成瘾者(网络游戏成瘾者)和物质成瘾者(烟草成瘾者)在奖励处理和认知控制任务上的差异，填补这一研究空白。

研究分两个阶段进行:行为研究和事件相关电位(ERP)研究。所有材料，包括问卷和实验程序都是用中文设计的(针对中国参与者)。第一阶段包括行为研究。行为研究包括三个实验:延退折扣任务、Simon-Stroop任务和主观评分任务。采用网络成瘾测试(IAT)和Fagerstrom尼古丁依赖测试(「丁ND)，从中国人群中筛选出93名参与者，分为对照组、吸烟组和问题网络游戏组。所有的参与者都被置于相似的条件下，研究两组在这两项实验中的表现差异。结果表明，三组间均存在群体效应。在延退折扣和反应抑制评分方面，两组成瘾者均与对照组存在显著差异。同时也发现，与对照组相比，他们对延退的折扣更大，并且表现出较差的抑制控制。在ERP研究中使用的吸烟、网络游戏和中性数字的图像被筛选和测试，以匹配他们的熟悉度、兴奋度、效价和渴望程度，使用主观评分任务。

ERP研究在第二阶段进行。采用简单赌博任务和停止信号任务，从对照组、网络游戏成瘾组和吸烟组共72名中国被试中采集ERP数据。简单赌博任务的结果表明，与两个成瘾组相比，正常组在高风险条件下比低风险条件有更负的SPN，这表明成瘾者的奖赏预期受损。与对照组相比，两个成瘾组的高风险选项(大额赢、大额输)的FRN峰值比低风险选项(小额赢、小额输)更低，表明两个成瘾组均存在冒险倾向，对高风险情况的敏感性降低。然而，在P3成分中，我们发现两个成瘾组之间的奖赏加工模式有所不同。吸烟组在赢的条件下P3成分具有较高的振幅，而网络成瘾组的P3成分的峰值振幅较低，说明网络游戏成瘾者中具有明显的回避系统而吸烟成瘾者没有。

Stop-Signal任务的结果也揭示了两组之间认知控制的一些共同和特异的模式。网络游戏成瘾组和吸烟组具有类似的认知控制的神经机制，表现在两组在Stop条件中的N2成分幅值低于Go条件，且反应正确率也更低。而特异性的认知控制机制体现在Stop条件中的N2和P3成分上。在吸烟线索条件下，吸烟组在成功抑制条件中的反应时间较长，SSRT较大，且N2和P3成分的幅值大于的抑制失败条件，表明烟草吸烟组的反应抑制作用受损。然而，与吸烟组相比，在游戏线索条件下，网络游戏成瘾组在成功抑制条件中的反应时间更快，SSRT更短，N2和P3成分的幅值更小，这表明网络游戏线索能够帮助网瘾者更加专注于任务，而吸烟组更容易被吸烟线索所干扰。虽然我们没有发现有统计学意义的群体一线索交互作用，但幅值的趋势使我们能够洞察在成瘾特定线索的情况下行为成瘾者和物质成瘾者的相似和不同的神经机制。

目前的研究发现，行为成瘾者和物质成瘾者的认知控制能力和奖赏加工能力都比不成瘾者差。与对照组相比，该研究还揭示了两个成瘾组之间的一些共同模式，即冲动、寻求感觉、冒险、倾向于冒险决策、延迟满足能力受损以及认知控制或反应抑制受损。行为成瘾组与物质成瘾组之间也存在着不同的模式。网络游戏上瘾者比烟草吸烟者更容易引起感觉寻求，而烟草吸烟者比网络游戏上瘾者更容易冲动。与网络游戏成瘾组相比，烟草吸烟组在存在烟草吸烟相关提示时的抑制控制较差，而在存在网络游戏提示的情况下，网络游戏成瘾组的抑制控制似乎有所改善。

本研究的结果可提供对行为和物质上瘾者常见和独特的认知和神经模式的洞察。了解行为和物质成瘾的常见和独特模式，有助于随后预防和干预这两种类型的成瘾。这可能有助于制定和调整针对两类成瘾者常见或明显症状的适当干预计划。

Tobacco smoking and problematic Internet gaming are two of the most common forms of addiction. Tobacco smoking is a substance addiction classified as "Tobacco use disorder" in DSM-5. It is defined as a prolonged use of tobacco over a long period of time having typical symptoms of substance addiction as craving, tolerance, withdrawal, unsuccessful quit attempts and impairments in social, occupational and personal life due to continued use of tobacco. Problematic Internet gaming, on the other hand, is an emerging health concern, classified as "Internet gaming disorder" in DSM-5. It is defined as a preoccupation and obsession with Internet games that interfere with the social, personal or occupational life. It also has typical symptoms of dependence as tolerance, withdrawal and failed attempts to quit the habit. It has been included in DSM-5 as a "Condition for Further Study", that requires more research. Both the addictions share some features as emotional dysregulation, impulsivity, poor coping skills, high risk for depression and anxiety, poor reward processing and cognitive control. According to a dual system model, addiction is caused by the imbalance between rewarding system and cognitive control system. However, it requires further study on whether there would be different mechanisms for substance addiction such as tobacco smoking, and behavioral addiction such as problematic Internet gaming. The current research study was designed to explore the common and distinct behavioral and neural patterns of reward processing and cognitive control in nicotine dependence and problematic Internet gaming, using dual system model.

The previous research studies have mostly focused on the commonalities between the substance addiction and behavioral addiction. However, no study has explored the common and distinct mechanisms of reward processing and cognitive control between the behavioral addicts and the substance addicts. The present study aims to fill this research gap, by comparing and contrasting the behavioral addicts (problematic Internet garners) and substance addicts (tobacco smokers) on reward processing and cognitive control tasks.

The study was conducted in two phases: Behavioral study and Event-Related Potential (ERP) study. All the materials, including questionnaires and experiment program were designed in Chinese (for Chinese participants). Phase 1 comprised of a behavioral study. The behavioral study included a set of three experiments: Delayed Discounting task, Simon Stroop task and Subjective Rating task. Using Internet Addiction Test (IAT) and Fagerstrom Test for Nicotine Dependence (FTND), 93 participants were screened from Chinese population into three groups: control group, tobacco smoking group, and problematic Internet gaming group. All the participants were subjected to similar conditions to study the group differences in their performance on the two experiments. The results indicated group effect among the three groups. Both the addiction groups were found to differ significantly from the control group on delay discounting and the response inhibition scores. They were indicated to discount delays more steeply and exhibit poor inhibitory control than their control counterparts. The images of tobacco smoking, Internet gaming and neutral figures to be used during ERP study were screened and tested to match their familiarity, arousal, valence, and craving using subjective rating task.

The ERP study was conducted in Phase 2. Simple Gambling task and Stop Signal were employed to collect ERP data from 72 Chinese participants in the three groups, control group, problematic Internet gaming group and the tobacco smoking group. The results of the simple gambling task indicated the SPN component to be more negative for the larger risk than the smaller risk for the control group than the two addiction groups, suggesting an impairment in the reward expectancy among the addicts. The two addiction groups were found to have a lower peak amplitude on FRN for the high risk choices (large loss, large win) than the low risk choices (small loss, small gain) than the control group, indicating the presence of risk-taking tendencies and decreased sensitivity towards high risk situations among both the addiction groups. However, on P3 component, we witnessed a distinct pattern of reward processing between the two addiction groups. The tobacco smoking group had high amplitudes on gain condition on P3 component, where the problematic Internet gaming group, on the contrary, had reduced peak amplitudes on P3 component, evident of avoidance system among the problematic Internet garners rather than the tobacco smokers (Kruschwitz et al., 2012).

The results of the stop signal also revealed some common and distinct patterns of cognitive control between the two groups. The common neural patterns of cognitive control among the problematic Internet gaming group and the tobacco smoking group were observed on low accuracy and lower peak amplitudes on N2 component on Stop trials than on Go trials. The distinct neural mechanism of cognitive control could be observed between the tobacco smoking group and the problematic Internet gaming group on Stop effect on N2 and P3 components. The tobacco smokers were found to have larger reaction times, larger SSRT and larger peak amplitudes on N2 and P3 component on successful inhibition trials than the unsuccessful inhibition trials with the tobacco smoking cues, indicating the impaired response inhibition among the tobacco smokers. However, in contrast to the tobacco smoking group, the problematic Internet gaming group was found to have faster reaction times, shorter SSRT, smaller peak amplitudes on N2 and P3 component on successful inhibition trials than the unsuccessful inhibition trials with the Internet gaming cues, suggesting the Internet gaming cues in the background actually helped the problematic Internet garners to focus more on the task in contrast to the tobacco smoking group, that were more distracted by the presence of tobacco smoking cues. Although we could not find statistically significant group*cue interaction effect, the tendency of the peak amplitudes gives us an insight into the similar and distinct neural mechanisms of behavioral addicts and substance addicts in the presence of addiction-specific cues.

The current study found both the behavioral addicts and the substance addicts to have poor cognitive control and reward processing than the non-addicts. The study also revealed some common patterns shared between both the addiction groups as impulsivity, sensation seeking, risk-taking, proneness to risky decision making, impaired ability of delayed gratification, and impaired cognitive control or response inhibition in contrast to the control group. Some distinct patterns were also found between the behavioral addiction and the substance addiction group. The problematic Internet garners were also indicated to be more sensation seeking than the tobacco smokers while tobacco smokers were found to be slightly more impulsive than the problematic Internet garners. The tobacco smoking group was found to have poor inhibitory control in the presence of tobacco smoking related cues in contrast to the problematic Internet gaming group, whose inhibitory control seemed to improve in the presence of the Internet gaming cues on the stop signal task.

The results of this study may provide an insight into the common and distinct cognitive and neurological patterns of the behavioral and substance addicts. The knowledge about common and distinct patterns of behavioral and substance addiction is useful for subsequent prevention and intervention of the two types of addiction. It may be helpful in devising and adapting suitable intervention plans targeting common or distinct symptoms of the two types of addicts.