奖赏对海洛因成瘾者执行功能的影响机制

一些研究发现海洛因成瘾者奖赏失调表现为:对海洛因相关线索的注意偏向、渴求感增加,对金钱奖赏表现出"即时收益优先"的高风险决策模式和对长时收益的敏感性降低。另一些研究发现海洛因成瘾者的执行功能存在障碍。奖赏失调和执行功能障碍在成瘾物质使用的维持和复吸中起着重要作用。双重竞争模型认为奖赏和执行功能的交互作用决定着行为的结果,但是奖赏对海洛因成瘾者执行功能的影响机制还不清楚。因此,拟使用事件相关电位技术来考察海洛因相关线索和金钱奖赏对不同戒断期成瘾者执行功能的影响机制,短期(1~3个月)、长期(18个月以上)海洛因戒断者和健康对照组被比较。这不仅有助于构建完善的成瘾理论体系,还有助于确定临床戒断后复吸的风险因素和不同戒断期的治疗目标。     

阅读障碍儿童的形音捆绑缺陷及其脑神经机制

形音捆绑缺陷研究是国内外阅读障碍研究领域的一个新方向。本文阐述了形音捆绑加工的理论与定义,综述了国内外研究者经常采用的三种形音捆绑的研究范式:配对联想学习、变化检测范式和线索回忆任务,介绍并分析了各研究范式的优缺点、适用范围及主要研究发现。同时,综述与评价了国内外有关阅读障碍形音捆绑缺陷的脑机制研究的主要结论及不足。最后,本文讨论了现有研究在实验设计和理论上的贡献与不足,提出了今后的研究方向和改进建议。     

高中生内隐、外显成就动机与学业拖延的关系

采用内隐联想测验和问卷法探讨高中生内隐、外显成就动机与学业拖延的关系。结果表明:(1)内隐、外显成就动机是相互独立的动机系统,但两者以显著的交互作用共同影响学业拖延;(2)不同动机组合的学生,拖延情况有显著差异:高内隐、高外显组的拖延最少,高内隐、低外显组的拖延最多;(3)动机越不一致,拖延越严重,动机一致性能够减少拖延;(4)成绩中等偏下的学生在学习过程的补救和总结上有更多的拖延。因此,学生只有具备了高内隐、高外显的一致性动机,才会出现最少的拖延。     

走神对中文阅读绩效的影响

选取36名大学生被试,采用探针检测的方法和逐句阅读范式,考察被试阅读中文材料时走神对阅读正确率和阅读时间的影响。结果发现:(1)中文阅读中出现走神的时间占34.80%;(2)走神会影响阅读理解,降低阅读理解正确率;(3)走神会导致阅读时间变慢。这些发现均证实走神对中文阅读绩效有影响,降低阅读理解正确率和减缓阅读时间。     

组织不公平与反生产行为的关系

本文以118名企业员工为被试,以自编实验材料和量表为研究工具,探讨组织不公平与反生产行为之间的关系,并考察了权力距离对组织不公平与反生产行为关系的调节作用。结果发现:当被试面对组织不公平情境时,倾向于实施反生产行为;组织不公平情境下,低权力距离组被试在反生产行为得分上显著高于高权力距离组个体,而在中性情境下,两组被试得分差异不显著,即权力距离在组织不公平与反生产行为之间起负向调节作用。由于反生产行为的产生常与组织不公平相关,因此本研究结果将有助于我们更好地理解反生产行为产生的原因,并从心理学角度帮助组织管理者制定减少反生产行为发生的措施。     

网站临场感能否增强女性购买意愿?

为了克服网络虚拟性的影响,网络商铺往往通过提升网站临场感以弥补购物体验不足的问题。那么,网站临场感是否会对女性消费者这一细分群体产生影响呢?本研究从网站临场感的视角出发,以女大学生为研究对象、服装网站为实验材料,采用实验法研究了网站临场感对女性网络购买意愿的影响及其发生机制。研究发现:网站临场感对女性网络购买意愿具有显著的正向影响;网站临场感可以通过风险感知和沉醉感的中介作用对女性网络购买意愿产生影响,且该中介作用包含了三条路径,即风险感知的中介作用、沉醉感的中介作用以及风险感知和沉醉感的链式中介作用。     

Study of behavioural and neural bases of visuo‐spatial working memory with an fMRI paradigm based on an n‐back task

The goal of this study was to propose a new functional magnetic resonance imaging (fMRI) paradigm using a language‐free adaptation of a 2‐back working memory task to avoid cultural and educational bias. We additionally provide an index of the validity of the proposed paradigm and test whether the experimental task discriminates the behavioural performances of healthy participants from those of individuals with working memory deficits. Ten healthy participants and nine patients presenting working memory (WM) deficits due to acquired brain injury (ABI) performed the developed task. To inspect whether the paradigm activates brain areas typically involved in visual working memory (VWM), brain activation of the healthy participants was assessed with fMRIs. To examine the task's capacity to discriminate behavioural data, performances of the healthy participants in the task were compared with those of ABI patients. Data were analysed with GLM‐based random effects procedures and t‐tests. We found an increase of the BOLD signal in the specialized areas of VWM. Concerning behavioural performances, healthy participants showed the predicted pattern of more hits, less omissions and a tendency for fewer false alarms, more self‐corrected responses, and faster reaction times, when compared with subjects presenting WM impairments. The results suggest that this task activates brain areas involved in VWM and discriminates behavioural performances of clinical and non‐clinical groups. It can thus be used as a research methodology for behavioural and neuroimaging studies of VWM in block‐design paradigms.     

Extraversion modulates functional connectivity hubs of resting‐state brain networks

Personality dimension extraversion describes individual differences in social behaviour and socio‐emotional functioning. The intrinsic functional connectivity patterns of the brain are reportedly associated with extraversion. However, whether or not extraversion is associated with functional hubs warrants clarification. Functional hubs are involved in the rapid integration of neural processing, and their dysfunction contributes to the development of neuropsychiatric disorders. In this study, we employed the functional connectivity density (FCD) method for the first time to distinguish the energy‐efficient hubs associated with extraversion. The resting‐state functional magnetic resonance imaging data of 71 healthy subjects were used in the analysis. Short‐range FCD was positively correlated with extraversion in the left cuneus, revealing a link between the local functional activity of this region and extraversion in risk‐taking. Long‐range FCD was negatively correlated with extraversion in the right superior frontal gyrus and the inferior frontal gyrus. Seed‐based resting‐state functional connectivity (RSFC) analyses revealed that a decreased long‐range FCD in individuals with high extraversion scores showed a low long‐range functional connectivity pattern between the medial and dorsolateral prefrontal cortex, middle temporal gyrus, and anterior cingulate cortex. This result suggests that decreased RSFC patterns are responsible for self‐esteem, self‐evaluation, and inhibitory behaviour system that account for the modulation and shaping of extraversion. Overall, our results emphasize specific brain hubs, and reveal long‐range functional connections in relation to extraversion, thereby providing a neurobiological basis of extraversion.