限制性饮食者对食物线索的认知偏向：行为和脑机制的证据

限制饮食是为了控制体重, 长期严格地控制进食的倾向。大量研究表明相对于非限制性饮食者, 限制性饮食者对食物线索尤其是高能量或高美味食物线索存在认知偏向。这种偏向是基于一定的脑神经基础的如前额叶背内侧, 小脑等区域。未来研究应设置严格的筛选标准, 运用视觉odd-one-out和学习-再认实验范式, 重视认知神经机制的探讨, 开展中国限制性饮食者对食物线索加工的认知机制和主要影响因素模型的系统研究。     

Memory Maintenance

ABSTRACT— Change in the synaptic communication between neurons—known as synaptic plasticity—plays a key role in learning and memory. It is not yet clear, however, whether the properties of synaptic plasticity are sufficient to account for long-term-memory maintenance. Recent studies have revealed that synaptic plasticity can indeed persist for weeks or months, as might be expected of a long-term-memory mechanism. However, memories encoded by neural systems are not static; they continue to evolve as new learning occurs. Furthermore, neural-network modeling has shown that synapses must be able to reconfigure their connection strengths during new learning if old information is to be preserved. Recent tests confirm that synapses, once modified, retain their capacity for further modification, indicating that they can indeed operate in the manner predicted to be necessary for memory maintenance in a dynamic learning network.     

双语者代码切换的认知与神经机制——从行为研究到脑成像研究

双语者代码切换的机制已引起心理语言学家和认知神经科学家的广泛关注。研究分别在行为层面和神经机制层面展开。发现,双语者在进行代码切换时会出现切换代价,切换代价来源于心理词典外部的语言任务图式之间的竞争,其机制可能与中央执行控制机制有密切联系,左侧额下回、双侧缘上回和背外侧前额叶等脑区参与了双语者的代码切换过程。文章还分析了在这一领域仍待研究的一些问题,并提出了进一步开展双语代码切换研究的建议。     

人工神经网络模型在心理学研究中的运用

人工神经网络是对真实神经元网络的粗略模拟,具有容错性、抗干扰性、高效性等特征,具有学习、记忆等强大的认知功能,因此适宜于心理学许多领域的模拟研究。借助神经网络模型不仅可以模拟和验证以往的实验室研究;还能深入探讨感知、联想、学习和记忆等认知过程的具体发生机理,把握其内在机制;它对探讨内隐记忆、内隐学习等无意识认知过程有极大的启发作用。     

Are unsupervised neural networks ignorant? Sizing the effect of environmental distributions on unsupervised learning

Learning environmental biases is a rational behavior: by using prior odds, Bayesian networks rapidly became a benchmark in machine learning. Moreover, a growing body of evidence now suggests that humans are using base rate information. Unsupervised connectionist networks are used in computer science for machine learning and in psychology to model human cognition, but it is unclear whether they are sensitive to prior odds. In this paper, we show that hard competitive learners are unable to use environmental biases while recurrent associative memories use frequency of exemplars and categories independently. Hence, it is concluded that recurrent associative memories are more useful than hard competitive networks to model human cognition and have a higher potential in machine learning.     

审美的神经机制研究及其美学意义

本文主要介绍了审美神经机制研究的初步成果,特别有关Zeki,Solso等人开创性的研究工作,并着重讨论了这些研究工作的美学意义,指出审美神经机制的研究不但在美学理论的确证方面,具有更强的说服力和广泛的应用性,而且在21世纪美学理论的重建方面,也一定会起着不可替代的重要作用。     

神经管缺陷的病因、预防与产前控制

神经管缺陷(NTDS)是一种常见的先天性中枢神经系统畸形,其发生率占据我国出生缺陷的前列。本文从其发病原因、产前诊断及预防措施进行系统分析,希望能找出一条降低其发生率的有效途径,从而进一步提高我国的人口素质。     

Autoshaping and automaintenance: a neural-network approach

This article presents an interpretation of autoshaping, and positive and negative automaintenance, based on a neural-network model. The model makes no distinction between operant and respondent learning mechanisms, and takes into account knowledge of hippocampal and dopaminergic systems. Four simulations were run, each one using an A-B-A design and four instances of feedfoward architectures. In A, networks received a positive contingency between inputs that simulated a conditioned stimulus (CS) and an input that simulated an unconditioned stimulus (US). Responding was simulated as an output activation that was neither elicited by nor required for the US. B was an omission-training procedure. Response directedness was defined as sensory feedback from responding, simulated as a dependence of other inputs on responding. In Simulation 1, the phenomena were simulated with a fully connected architecture and maximally intense response feedback. The other simulations used a partially connected architecture without competition between CS and response feedback. In Simulation 2, a maximally intense feedback resulted in substantial autoshaping and automaintenance. In Simulation 3, eliminating response feedback interfered substantially with autoshaping and automaintenance. In Simulation 4, intermediate autoshaping and automaintenance resulted from an intermediate response feedback. Implications for the operant-respondent distinction and the behavior-neuroscience relation are discussed.     

主观幸福感的脑机制

主观幸福感是社会认知领域一直关注的重要问题。Kahneman等人提出的评价系统模型为主观幸福感的研究提供了基本框架。主观幸福感形成过程中,评价系统的主要产物包括即时效用、回忆效用、抉择效用和预期效用,这些效用都有着各自特殊的神经机制。主观幸福感的影响因素分为内部和外部因素,它们也对应着各异的神经基础。未来主观幸福感领域的研究应遵循生理机制和心理机制相结合的整合研究思路。     

后悔的认知机制和神经基础

后悔是基于对不利或相对不利行为结果的反事实思维诱发的一种复杂的负性社会情绪,对我们日常生活的决策和身心健康具有重大的影响。与失望情绪相比,后悔在现象学、产生条件以及评价方式等方面具有明显的差异。后悔不仅会受到个体的行为方式、人格特征、归因等因素的影响,而且还会受到结果信息属性的影响。后悔的预期和体验涉及的功能性脑区主要包括：眶额皮层、扣带前回、海马、杏仁核。研究后悔的实验方法和技术手段有待于进一步拓展,后悔的认知机制和神经基础还有待于进一步探讨和完善