Reward Density And Variable-interval Schedule Performance In An Open Economy

There is no general agreement regarding the form of the relation between response rate and reinforcement rate when single schedules of reinforcement are studied in an open economy. The present study assessed the form of this relation using reward density, which incorporates both reinforcement rate and duration of access to food, as an independent variable. Reward density was manipulated with 4 pigeons by changing the value of the variable-interval schedule, the hopper duration, or both. The relations between response rate and reward density were sharply rising and hyperbolic in 3 of 4 pigeons, replicating results obtained by Catania and Reynolds (1968). Because eating efficiency was lower in conditions that provided longer hopper durations, programmed reward densities differed from obtained reward densities. When response rates were examined as a function of obtained reward densities, the same relations were demonstrated more strongly. In further clarifying the relation between response rate and reward density in an open economy, these results lend support to the conclusion that open and closed economies yield different behavioral effects.     

成瘾药物心理依赖及复发的脑机制研究

围绕学习、记忆、情绪及应激等心理因素与复发的关系,应用阿片类物质心理依赖研究条件性位置偏爱,条件性位置厌恶,Morris水迷宫量化觅药动机模型,行为及条件性行为敏感化等多种动物行为模型,从情绪相关学习、记忆在成瘾行为中的作用,不同神经核团与神经递质系统活动性的改变,应激相关因素易化的成瘾易感性,自然奖赏与成瘾药物奖赏相关记忆的比较研究等方面,对应激与记忆相关的吗啡心理依赖及复发的脑机制进行了系列研究     

fMRI responses to Jung's Word Association Test: implications for theory,treatment and research

Jung's Word Association Test was performed under fMRI conditions by 12 normal subjects. Pooled complexed responses were contrasted against pooled neutral ones. The fMRI activation pattern of this generic ‘complexed response’ was very strong (corrected Z scores ranging from 4.90 to 5.69). The activation pattern in each hemisphere includes mirror neurone areas that track ‘otherness’ (perspectival empathy), anterior insula (both self‐awareness and emotional empathy), and cingulated gyrus (self‐awareness and conflict‐monitoring). These are the sites described by Siegel and colleagues as the ‘resonance circuitry’ in the brain which is central to mindfulness (awareness of self) and empathy (sense of the other), negotiations between self awareness and the ‘internal other’. But there is also an interhemispheric dialogue. Within 3 seconds, the left hemisphere over‐rides the right (at least in our normal subjects). Mindfulness and empathy are central to good psychotherapy, and complexes can be windows of opportunity if left‐brain hegemony is resisted. This study sets foundations for further research: (i) QEEG studies (with their finer temporal resolution) of complexed responses in normal subjects (ii) QEEG and fMRI studies of complexed responses in other conditions, like schizophrenia, PTSD, disorders of self organization.     

Children's Graffiti: Visual Communication from a Developmental Perspective

The graffiti of children, an unobtrusive measure collected in Puerto Rican natural settings, revealed the children's views about the world. Results show that these graffiti reflect a wide variety of content related to the child's immediate life experiences such as concerns with their self-identity, interpersonal relations, cultural understandings, sexuality, and religious and political beliefs.     

Semantic embodiment,disembodiment or misembodiment? In search of meaning in modules and neuron circuits

“Embodied” proposals claim that the meaning of at least some words, concepts and constructions is grounded in knowledge about actions and objects. An alternative “disembodied” position locates semantics in a symbolic system functionally detached from sensorimotor modules. This latter view is not tenable theoretically and has been empirically falsified by neuroscience research. A minimally-embodied approach now claims that action–perception systems may “color”, but not represent, meaning; however, such minimal embodiment (misembodiment?) still fails to explain why action and perception systems exert causal effects on the processing of symbols from specific semantic classes. Action perception theory (APT) offers neurobiological mechanisms for “embodied” referential, affective and action semantics along with “disembodied” mechanisms of semantic abstraction, generalization and symbol combination, which draw upon multimodal brain systems. In this sense, APT suggests integrative-neuromechanistic explanations of why both sensorimotor and multimodal areas of the human brain differentially contribute to specific facets of meaning and concepts.     

Does equity sensitivity moderate the relationship between effort–reward imbalance and burnout

The model of effort–reward imbalance (ERI) received considerable research attention in the job stress literature. However, very scarce research investigated individual differences as moderators between ERI and stress. The present study is aimed at examining the combined effects of ERI, overcommitment (OVC), and the interaction between ERI and overcommitment on burnout (i.e., emotional exhaustion, cynicism, and inefficacy) and the moderating role of equity sensitivity. A questionnaire measuring ERI, burnout, and equity sensitivity was administered to 159 employees. Regression analyses were conducted to test the proposed relations and moderating hypotheses. ERI was negatively related to inefficacy and overcommitment was positively related to emotional exhaustion and cynicism. In addition, equity sensitivity was found to moderate the effect of overcommitment on emotional exhaustion and inefficacy. The findings emphasize the detrimental effect overcommitment may have on employee's mental health and suggest that the ERI model components may be closely related to perceptions of organizational justice.     

The Effects of Frequency of Social Interaction and Relationship Closeness on Reward Allocation

In this study of how the frequency of interaction affects decisions on reward allocation, 320 Chinese adults were randomly assigned to 8 conditions and instructed to read a scenario describing 2 co-workers completing a task and obtaining a bonus. The 8 conditions differed in the type of relationships, the frequency of past interaction between co-workers, and the possibility of future interaction. Each participant was instructed to act as the allocator and to hypothetically allocate a monetary reward to the co-worker. The results indicated that both past interaction and future interaction between the co-workers significantly influenced the allocation decision. These results also suggested that the frequency of 2 individuals' past interaction can be predictive of the closeness of their relationship.     

情景变换诱发已消退恐惧记忆重现的神经环路

暴露疗法是治疗创伤后应激障碍的主要行为疗法。当被试反复暴露于可引起恐惧反应的条件刺激(如白噪音), 但却不伴有非条件刺激(如足底电击)时, 恐惧记忆将被消退, 形成消退记忆。但恐惧记忆并未从根本上被擦除, 当被试在消退训练以外的情景暴露于条件刺激时, 已消退的恐惧记忆将会重现。海马、内侧前额叶皮层、杏仁核等脑区及其相互连接的神经环路是情景诱发恐惧记忆重现的生理基础。情景变化诱发恐惧记忆重现过程中, 海马可能是通过直接投射至杏仁核基底核、杏仁核外侧核或通过边缘前皮质间接调控杏仁核基底核、杏仁核外侧核的功能, 产生恐惧反应。