网络成瘾倾向者在视觉工作记忆引导下的注意捕获

采用工作记忆任务和视觉搜索任务相结合的双任务范式, 探讨网络成瘾倾向者在视觉工作记忆引导下的注意捕获。实验1考察了单一分心刺激视场中分心刺激的性质对网络成瘾倾向者选择性注意的影响, 实验2通过控制匹配试验出现的概率来诱发不同的抑制动机, 探讨多分心刺激视场中两种抑制动机下网络成瘾倾向者的注意表现。结果发现：(1)无论在单一分心刺激还是多分心刺激视场中, 网络成瘾倾向被试的目标搜索反应时均显著短于正常组被试, 且两组的搜索正确率没有差异。(2)在单一分心刺激视场中, 无论是与工作记忆项目匹配还是不匹配的分心刺激都会捕获正常组被试的注意, 但不会捕获网络成瘾倾向被试的注意。(3)在多分心刺激视场中, 当抑制动机水平较低时, 两组被试均对匹配分心物产生注意捕获效应, 且网络成瘾倾向被试受工作记忆引导的注意捕获效应小于正常组被试; 当抑制动机较高时, 两组被试均对匹配分心物产生注意抑制效应, 且没有差异。研究结果表明, 面对非网络相关视觉刺激时, 网络成瘾倾向者受工作记忆引导的注意捕获效应小于正常组, 并表现出了知觉加工上的优势。

The Attentional Capture of Internet Addicts under the Guidance of Visual Working Memory

Some studies have demonstrated an improved selective attention of Internet Addicts compared with normal people. However, most of these studies were done based on the single-task experimental paradigm, in which participants were required to perform only a visual search task. This single-task paradigm has neglected the inseparable relationship between the visual working memory and selective attention. In the present study, we employed a dual-task paradigm that required the participants to perform a visual search task while keeping an object in working memory. The purpose of this study was to exam the differences of attentional capture between Internet Addicts and normal people. In our experiments, participants were instructed to remember a color object as the target item, and then to seek the target among five distractors. Experiment 1 used a single distractor under three conditions: (1) the distractor matched with the target item in color; (2) the distractor differed from the target item in color; (3) the distractor had no color. There were 16 participants in the Internet addition group (13 male, 18~22 years old, M = 19.25, SD = 0.86) and 24 participants in the control group (18 male, 18~20 years old, M = 18.96, SD = 0.84). Experiment 2 used multiple distractors under two conditions: (1) three (out of five) distractors matched with the target item in color and shape (matching trials); (2) all five distractors differed from the target item in color and shape (control trials). The proportion (20% or 80%) of matching trials was varied across different experimental groups to induce different levels of inhibition motivation. There were 31 participants (21 male, 18~22 years old, M = 19.35, SD = 1.05) in the Internet addition group and 32 participants (22 male, 18~20 years old, M = 19.56, SD = 1.05) in the control group. Repeated-measures ANOVA was used to analyze the RTs. In both experiments, participants in the Internet addition group responded faster than those in the control group. There was no evidence for a speed-accuracy trade-off in both groups. When there was only one distractor in the search task (Experiment 1), the distractor would capture the attention of participants in the control group under all conditions, but would not capture the attention of participants in the Internet addition group. When there were multiple distractors in the search task (Experiment 2), the attentional capture effects differed by the level of inhibition motivation. At a low level of inhibition motivation, search RTs were shorter in matching trials than in control trials for both groups, demonstrating a classical memory-based attention capture effect induced by memory-matching distractors. This effect was smaller in the Internet addition group. At a high level of inhibition motivation, search RTs were shorter in matching trials than in control trials, suggesting that there was a memory-based attention inhibition affected by top-down control. There was no difference in the attention inhibition effect between the two groups. These findings suggest that Internet Addicts differ from the normal controls in the attention capture led by working memory. When facing with common irrelevant visual stimuli, the Internet Addicts may perform faster in visual processing.