Influence of seasonally adjusted exposure to cold and darkness on cognitive performance in circumpolar residents

The effects of seasonally adjusted 24-h exposure to cold and darkness on cognitive performance in urban circumpolar residents was assessed in 15 male subjects who spent three 24-h periods in a climatic chamber at 65° latitude during the winter (January–March) and/or summer (August–September). Each subject was exposed to three different environmental conditions in random order: (1) 22 °C temperature and 500 lx lighting; (2) 10 °C temperature and 500 lx lighting; and (3) 10 °C temperature and 0.5–l lx lighting. Accuracy on an addition-subtraction task was significantly greater in the summer than in the winter ( p = 0.038), while accuracy on a repeated acquisition task was significantly greater in the winter than in the summer ( p < 0.001). Independent of season, exposure to cold and darkness was significantly associated with a decline in response time on five cognitive tests, an improvement in accuracy on three tests measuring complex cognitive tasks, and a decline in accuracy on two tests measuring simple tasks. Increased performance on complex tasks may result from increased arousal in response to the combination of cold temperatures and dim light characteristic of the winter in urban circumpolar settings.     

Visual evoked potentials to the geometric forms in the randomized presentation

Two outlined geometric figures, an equilateral triangle and a circle, of equal contour length, were randomly presented at a fixed position in the lower or upper part of the visual field (LVF and UVF). Transient visual evoked potentials (VEPs) were recorded monopolarly from the inion (I), 5, 10, 15 cm above it (I5, I10, I15) and Fz, for 12 subjects. Grand-averaged VEPs were computed. A negative (N) wave (averaged peak latency 155 ms) was identified in the LVF and a positive (P) wave (130 ms) in the UVF. In the LVF, the N amplitude of the triangle was significantly larger than that of the circle at I5 and I. Regarding the P wave in the UVF, the triangle was of a significantly longer latency than the circle at I15, I10 and I5. The enhancement of the N amplitude for the triangle in the LVF is not attributable to the arousal caused by the preparatory state for the figure, since the subject could not predict the figure to be presented next or its position.     

THEORETICAL,PRACTICAL, AND SOCIAL ISSUES IN BEHAVIORAL TREATMENTS OF OBESITY

Although showing superior maintenance, behavioral treatments of obesity typically produce small weight losses at a decelerating rate. Rather than reflecting poor compliance with treatment, these findings are consistent with known compensatory metabolic changes that operate to slow weight loss and promote regain. Other problems associated with dieting include failure of caloric regulation, hyper-responsivity to food palatability, and hunger, which is greatest under conditions of moderate restriction and unpredictability of access to food. The inevitability of treatment failure in many instances must be faced and efforts made to prevent further worsening of the obese patient's self-esteem. Prognosis and treatment planning may be aided by consideration of the historical difficulties of weight loss, the degree of hunger experienced on diets, which may reflect important physiological differences among individuals, and the use of food to optimize arousal level. Full involvement of the patient in setting goals and planning treatment is recommended.     

情绪对联合行动中共同表征能力的影响机制

采用联合Simon任务通过3个实验探究不同情绪维度对联合任务中共同表征能力的影响机制。实验1a、1b分别考察在高、低唤醒度条件下不同效价对个体共同表征能力的影响; 实验2在此基础上进一步探索动机维度在其中的作用。结果发现：无论效价高低, 高唤醒度都是提高个体共同表征能力的关键因素, 且动机强度在其中起一定调节作用; 而在低唤醒度条件下, 高效价会起一定补偿作用。上述结果很好地支持了参照编码假说, 也澄清了情绪不同维度对联合动作表征的影响机制。     

Disentangling the facilitating and hindering effects of threat-related stimuli – A visual search study

Although large body of research has demonstrated the attention-grabbing nature of threat-related stimuli, threat could also facilitate attentional processes. Previous studies suggest a linear relationship between the facilitating effect of the arousal level conveyed by threat and performance on visual search tasks. Due to the temporal competition bias favouring stimuli with higher arousal level, this could be more pronounced for shorter onset times. Here, through two experiments we aimed to disentangle the two effects by using a visual search paradigm that allowed us to separate the emotional stimuli and the cognitive task. We manipulated stimulus onset time and threat intensity. Participants saw neutral and threatening pictures as priming stimuli, and then, they had to find numbers in ascending order in a matrix array. We measured the reaction time for finding the first number, and search time for finding all the numbers. Our results showed that when the priming stimulus is presented, longer threatening pictures produced longer reaction times compared to neutral ones, which was reversed with increase in arousal. We did not find any significant effects for the shorter onset time. Further theoretical and methodological implications are discussed.     

夜间进食综合征的研究进展

夜间进食综合征是一种表现为早晨没有食欲、晚饭后过量进食或夜间醒来进食的饮食障碍,并且与睡眠问题相关。在国内外文献进行分析研究的基础上,本文先后介绍了夜食症的概念内涵、发病的生理神经机制及主要的干预措施和治疗手段,并对现有研究的不足进行总结,提出了未来研究的方向,旨在为研究者在此领域的进一步探索提供参考。     

Hemisphere Specialization as an Aid in Early Infancy

In order that different directions of attention can be organized, they have to be labeled and assessed. A statement of a general problem can be regarded as a label for a general direction of attention. Hope about it, as the perceived probability of sufficient success, on the basis of work done, can be regarded as an assessment. It can be argued that a young infant meets an impasse arising from the work on 2 incompatible general problems, (1) that of raising hope of certainty about the environment (linked to the arousal system because repeated stimulation has less effect), and (2) that of raising hope of producing effects (linked to the activation system because here some effect must be produced before activity can cease). A certainty–right hypothesis, that the right hemisphere deals with the certainty problem and the left deals with the producing-effects problem, and hence keeps work on the two problems apart in early infancy while the corpus callosum is undeveloped, and that a matching specialization continues in later life, is supported.     

同性恋形成机制探析

尽管人们对同性恋越来越宽容,但它仍是一种反常规现象。让现有同性恋者放弃同恋行为来减少同性恋难度很大,也不人道。在同性恋形成机制的问题上,有生理机制说和社会心理机制说。本文倾向于社会心理机制说。尝试从同性恋的社会心理机制上把同性恋分为两个形成亚型,并说明了每个亚型形成的具体过程。