Rapid acquisition of preference in concurrent chains: effects of d-amphetamine on sensitivity to reinforcement delay

The purpose of this study was to examine effects of d-amphetamine on choice controlled by reinforcement delay. Eight pigeons responded under a concurrent-chains procedure in which one terminal-link schedule was always fixed-interval 8 s, and the other terminal-link schedule changed from session to session between fixed-interval 4 s and fixed-interval 16 s according to a 31-step pseudorandom binary sequence. After sufficient exposure to these contingencies (at least once through the pseudorandom binary sequence), the pigeons acquired a preference for the shorter reinforcement delay within each session. Estimates of the sensitivity to reinforcement immediacy were similar to those obtained in previous studies. For all pigeons, at least one dose of d-amphetamine attenuated preference and, hence, decreased estimates of sensitivity to reinforcement immediacy; in most cases, this effect occurred without a change in overall response rates. In many cases, the reduced sensitivity to reinforcement delay produced by d-amphetamine resulted primarily from a decrease in the asymptotic level of preference achieved within the session; in some cases, d-amphetamine produced complete indifference. These findings suggest that a reduction in the sensitivity to reinforcement delay may be an important behavioral mechanism of the effects of psychomotor stimulants.     

高绩效工作系统负面影响的潜在机制

高绩效工作系统是一系列以提升组织绩效为目标的人力资源管理实践的集合或捆绑。已有研究发现高绩效工作系统也可能对员工产生负面影响。针对此问题, 本文首先澄清了高绩效工作系统的概念, 从管理理念分析其可能产生负面影响的原因。厘清了高绩效工作系统对组织和员工带来的不同效果, 从多元论的视角分析其负面影响的来源。基于工作要求−资源模型、自我决定理论、归因理论和过犹不及效应, 阐释高绩效工作系统对员工负面影响的内在机制。并进一步从个人和组织层面分析高绩效工作系统产生负面影响的边界条件。最后, 提出未来的研究方向和建议。     

条件化恐惧复发的动物模型及相关神经机制

创伤后应激障碍(PTSD)受到国内外普遍关注, 临床上常用的暴露疗法就是基于消退原理, 但经过治疗的患者复发率仍然很高, 这提示抑制复发可能是治疗创伤后应激障碍的关键问题。条件性恐惧复发的动物模型主要包括重建、续新和自发恢复, 但是对续新的研究最多。前人的研究结果表明, 恐惧复发具有异质性, 但海马、前额叶与杏仁核三大脑区或许构成了共同的神经基础。文章从脑区机制及药理干预方面进行了综述, 以期对基础研究和临床诊治提供参考。     

技能学习与重复启动基本机制问题的探讨

关于技能学习与重复启动的基本机制问题在学术界存有很大的争议．对其进行探讨将会对从整体上考察程序性记忆的性质产生重要的影响。此文主要从函数形式、相关性和增减模式的理论分析,数字输入任务的计算模型．程序性记忆和学习的观点几个方面探讨了有关问题,说明技能学习与重复启动是程序性记忆的不同表现形式,它们有着相同的基本机制。     

Impaired long-term potentiation and enhanced neuronal excitability in the amygdala of CaV1.3 knockout mice

Previously, we demonstrated that mice in which the gene for the L-type voltage-gated calcium channel Ca_V1.3 is deleted (Ca_V1.3 knockout mice) exhibit an impaired ability to consolidate contextually-conditioned fear. Given that this form of Pavlovian fear conditioning is critically dependent on the basolateral complex of the amygdala (BLA), we were interested in the mechanisms by which Ca_V1.3 contributes to BLA neurophysiology. In the present study, we used in vitro amygdala slices prepared from Ca_V1.3 knockout mice and wild-type littermates to explore the role of Ca_V1.3 in long-term potentiation (LTP) and intrinsic neuronal excitability in the BLA. We found that LTP in the lateral nucleus (LA) of the BLA, induced by high-frequency stimulation of the external capsule, was significantly reduced in Ca_V1.3 knockout mice. Additionally, we found that BLA principal neurons from Ca_V1.3 knockout mice were hyperexcitable, exhibiting significant increases in firing rates and decreased interspike intervals in response to prolonged somatic depolarization. This aberrant increase in neuronal excitability appears to be at least in part due to a concomitant reduction in the slow component of the post-burst afterhyperpolarization. Together, these results demonstrate altered neuronal function in the BLA of Ca_V1.3 knockout mice which may account for the impaired ability of these mice to consolidate contextually-conditioned fear.     

两种自我保护机制：记忆忽视和自我免疫

当自我概念的稳定性受到威胁时,人们有时会采取自我保护手段来加以应对。在诸多自我保护方式中,记忆忽视加工是指个体在接触具威胁性的信息时进行选择性记忆,自然地忽视此类信息而不让其进入精加工,以消除该信息对自我概念的伤害;自我免疫加工是指个体通过对具威胁性信息的适宜操作界定来强调自己的优势能力,并重新评估自己的弱点,从而策略性地实现自我概念的稳定。文章从两种加工的认知机制角度来介绍和评述该领域的研究概况、研究方法与研究展望,借以引起对自我保护机制研究新进展的关注     

On the influence of causal beliefs on the feeling of agency

The sense of agency is the experience of being the origin of a sensory consequence. This study investigates whether contextual beliefs modulate low-level sensorimotor processes which contribute to the emergence of the sense of agency. We looked at the influence of causal beliefs on ‘intentional binding’, a phenomenon which accompanies self-agency. Participants judged the onset-time of either an action or a sound which followed the action. They were induced to believe that the tone was either triggered by themselves or by somebody else, although, in reality, the sound was always triggered by the participants. We found that intentional binding was stronger when participants believed that they triggered the tone, compared to when they believed that another person triggered the tone. These results suggest that high-level contextual information influences sensorimotor processes responsible for generating intentional binding.     

Cognitive Behavioural Therapy and Applied Relaxation for Generalized Anxiety Disorder: A Time Series Analysis of Change in Worry and Somatic Anxiety

The present study examined symptom change profiles in patients with generalized anxiety disorder (GAD) receiving either cognitive behavioural therapy (CBT) or applied relaxation (AR). It was hypothesized that (a) changes in worry would uniquely predict changes in somatic anxiety for most participants receiving CBT and (b) changes in somatic anxiety would uniquely predict changes in worry for most participants in the AR condition. Twenty participants (CBT n = 10; AR n = 10) completed daily ratings of worry and somatic anxiety during therapy, and multivariate time series analysis was used to assess the causal impact of each variable on the other. The hypotheses were not supported because we found no evidence of a match between individual symptom change profiles and treatment condition. Rather, a bidirectional relationship between worry and somatic anxiety was observed in 80% of participants receiving CBT and 70% of participants receiving AR. When only treatment responders were considered, 83% of participants receiving CBT and 86% of those receiving AR had such a bidirectional effect. The findings are discussed in terms of models of psychopathology that posit dynamic interactions between symptom clusters and in terms of the value of examining treatment mechanisms at the individual level.     

Organisational interventions to improve employees' health and wellbeing: A realist synthesis

Although organisational interventions have shown promising results in improving employees' health and wellbeing, reviews of the effectiveness of such interventions conclude results are inconsistent. Realist synthesis is considered an appropriate method of literature review to improve the consistency of empirical evidence by developing generalisable statements of ‘what works for whom in which circumstances’. In this article, to identify and synthesise existing evidence from the empirical studies of organisational interventions, we conducted a realist synthesis according to the RAMESES publication standards. We reviewed 28 articles. Six realist programme theories were developed that explain how different mechanisms of organisational interventions may bring about different outcomes in different contexts. These realist programme theories are based on the process mechanisms of implementation adherence, communication, employees' participation, senior management support, middle management support and external consultants/researchers support. This realist synthesis enhances the understanding of how organisational interventions may improve employees' health and wellbeing, in which contexts, and for which group of employees. As such, it makes an important potential contribution to designing, implementing and evaluating future organisational interventions.     

青少年风险决策的发展认知神经机制

随着认知神经科学技术的发展, 青少年风险决策的发展认知神经机制成为了新近的一个热点课题。从双系统理论模型(社会情感神经网络系统、认知控制神经网络系统)出发, 对与青少年风险决策相关的大脑结构、功能的变化进行了阐述, 重点分析了新近的大脑功能连接、脑网络的研究; 阐述了青少年风险决策认知神经机制的主要理论模型：双系统模型和三角模型。未来研究还应加强对认知神经机制理论模型的检验、整合和创新, 从社会认知神经科学的角度深入研究社会参照系统(同伴关系、亚文化等)在青少年风险决策中的作用及机制, 以及从认知神经层面如何预防和干预青少年高风险行为。