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891.
892.
Objective. A randomised controlled trial (RCT) was conducted to evaluate a three-hour face-to-face physical activity (PA) intervention in community-dwelling older German adults with four groups: The intervention group (IG) received behaviour change techniques (BCTs) based on the health action process approach plus a views-on-ageing component to increase PA. The second intervention group ‘planning’ (IGpl) contained the same BCTs, only substituted the views-on-ageing component against an additional planning task. An active control group received the same BCTs, however, targeting volunteering instead of PA. A passive control group (PCG) received no intervention.

Design. The RCT comprised 5 time-points over 14 months in N = 310 participants aged 64+.

Main outcome measures. Self-reported as well as accelerometer-assessed PA.

Results. Neither PA measure increased in the IG as compared to the other groups at any point in time. Bayes analyses supported these null-effects.

Conclusion. A possible explanation for this null-finding in line with a recent meta-analysis is that some self-regulatory BCTs may be ineffective or even negatively associated with PA in interventions for older adults as they are assumed to be less acceptable for older adults. This interpretation was supported by observed reluctance to participate in self-regulatory BCTs in the current study.  相似文献   

893.
Michele   K.   Surbey  Gavin   R.   Brice 《心理学报》2007,39(3):513-522
研究分为问卷调查与实验研究两部分。首先,40名女性和33名男性完成有关自感配偶价值评价(SPMV)和择偶偏爱策略的问卷调查,问卷调查结果是实验研究中数据分析的基线。其次,第二部分实验开始后,被试会得到实验者编造的他人潜在择偶对象的积极正面评价,其目的在于提高被试的SPMV。可以假设,男性的SPMV与随意性行为的认同或追求有正相关,男性SPMV的提高将会更加偏爱短期的性策略;女性SPMV与随意性行为不存在相关,女性SPMV的提高不会改变女性的性策略。研究结果显示,SPMV高基线水平的男性更加认可随意性行为,男性SPMV的提高与短期策略选择的增加有关。另外,SPMV提高,而不是一般自尊的提高,与择偶策略的改变具有相关。本研究结果没有证实,与长期稳定的性关系相比,SPMV的基线水平或是提高与女性对随意性行为的认同或追求之间存在相关  相似文献   
894.
In a previous study (H. J. Bischof & K. Herrmann (1986), Behavioral Brain Research, 21, 215-221) we demonstrated that four forebrain areas of the zebra finch male are activated in situations which arouse the animal, for example when the birds are chased around the cage or when they are exposed to a female. These areas, the hyperstriatum accessorium-dorsale (HAD), a part of the medial neo-hyperstriatum (MNH), the lateral neo-hyperstriatum (LNH), and a portion of the caudal archi-neostriatum (ANC), show enhanced 2-[14C]deoxyglucose (2-DG) uptake according to the experimental situation. On the basis of these experiments, we examined whether the activation of the areas is correlated with motor activity and is influenced by different isolation times prior to a 2-DG experiment, where courtship of the male birds is elicited by exposing them to a female zebra finch. For this purpose, we isolated male zebra finches for 1 day, 1 week, or 8 weeks, respectively, before we injected the 2-DG and exposed the birds to a female. During the experiment, besides other activities, the number of song motifs performed by the bird and the frequency of changing perches was recorded. Our experiments demonstrate that there is a weak negative correlation between motor activity and 2-DG uptake, and a positive correlation between isolation time and 2-DG uptake. We suggest that long isolation blocks courtship behavior by some unknown mechanisms, and that the "internal drive" of the animal, which possibly corresponds with the activity of the four forebrain areas, is enhanced by isolation and by the fact that the birds do not perform the consummatory behavior. Our results also demonstrate that the 2-DG method can show up small differences in the internal state of an animal, which cannot easily be detected by behavioral measurements.  相似文献   
895.
Investigation of interlimb synergy has become synonymous with the study of coordination dynamics and is largely confined to periodic movement. Based on a computational approach this paper demonstrates a method of investigating the formation of a novel synergy in the context of stochastic, spatially asymmetric movements. Nine right-handed participants performed a two degrees of freedom (2D) "etch-a-sketch" tracking task where the right hand controlled the horizontal position of the response cursor on the display while the left hand controlled the vertical position. In a pre-practice 2D tracking task, measures of phase lag between the irregularly moving target and the response showed that participants controlled left and right hands independently, performance of the right hand being slightly superior to the left. Participants then undertook 4 h 16 min distributed practice of a one degree of freedom etch-a-sketch task where the target was constrained to move irregularly in only the 45 degrees direction on the display. To track such a target accurately participants had to make in-phase coupled stochastic movements of the hands. In a post-practice 2D task, measures of phase lag showed anisotropic improvement in performance, the amount of improvement depending on the direction of motion on the display. Improvement was greatest in the practised 45 degrees and least in the orthogonal 135 degrees direction. Best and worst performances were no longer in the directions associated with right and left hands independently, but in directions requiring coupled movements of the two hands. These data support the proposal that the nervous system can establish a model of novel coupling between the hands and thereby form a task-dependent bimanual synergy for controlling the stochastic coupled movements as an entity.  相似文献   
896.
Abstract

Substantial empirical research has been undertaken on cardiovascular reactivity (CVR). however interpretation of this research is hampered by a lack of theoretical frameworks. This paper develops a framework initially stimulated by evidence demonstrating that the cardiovascular system increases in activity during communication, and that the extent of this activation depends upon numerous and diverse psychosocial factors. We attempt to account for this phenomenon using merit post-structuralist ideas concerning the constructive nature of language and its centrality to an individual's sense of self. Our theoretical framework proposes that the CVR exhibited during language use is explicable in terms of self-construction - From this analysis we hypothesised that CVR would differ across conversations about private self. public self and non-self topics, and that these differences would depend upon people's speaking histories. We found that the blood pressure and heart rate of 102 women was most reactive when they talked in a laboratory with a stranger about aspects of their private self, and least reactive during non-self talk, whilst their heart rate was most reactive during talk about their public self. Overall the results highlight the inextricable link between our inherent socialness and our cardiovascular systems.

SUMMARY

The explanatory scheme outlined here is an attempt to provide a social reconceptualisation of a phenomenon that is typically interpreted in individualistic psychophysiological terms, and which is consistent with the notion that repeated exposure to situations which provoke large haemodynamic changes may lead to CHD disease progression. The explanation draws heavily on post-structuralist ideas regarding language, and the social constructionist notion that engaging in language use is central to constructing and maintaining a sense of self. This sense of self is a central theoretical entity in our everyday lives, produced and maintained in our interactions with others. We argue that it is this centrality of self-construction that helps to explain the extraordinary consistency of elevated CVR in conversation. Further, we have noted the striking parallels between those features of conversations that make the self salient, and those that have been associated with elevated CVR. To examine it more explicitly, it needs to be tested empirically with new data, using explicitly derived operationalisations and hypotheses.  相似文献   
897.
898.
Prior research suggests children’s involvement in organized activities predicts positive outcomes, although benefits for youth with psychosocial deficits remain unclear. This study examines if activity participation predicts response to a group therapy program for children with psychosocial deficits and if improvements depend on children’s functioning within the organized activity context. Participants were 178 children (M age?=?9.6 years) enrolled in a group therapy program. Greater activity participation significantly predicted improvements in family functioning and social skills, suggesting the value of participation in organized activities for youth with psychosocial deficits.  相似文献   
899.
A common technique in research into cerebral asymmetry in both normal and clinical populations involves the use of lateralized visual displays. The validity of this approach depends on several generally implicit assumptions about the character of the cognitive processes involved. For example, when words are used as stimuli, cognitive processing is assumed to involve either "whole-word" or "ends-in" analysis. In this way, both hemispheres are assumed to have equal opportunities to recognize the word. These assumptions are critical, because if they are wrong, explanations based on established perceptual principles may provide a sufficient and more parsimonious explanation for hemifield asymmetries than hemispheric specialization theories. This point is developed and illustrated with particular reference to word recognition and classification. From a purely perceptual viewpoint, the right visual field advantage observed in tasks using word stimuli is to be expected given the presence of systematic biases in favor of initial characters or features of words and the relationship between retinal eccentricity and visual acuity. In other words, there is no need nor justification for a hemispheric account of visual field differences in such tasks. Some of the limiting conditions and theoretical implications of this argument are identified and discussed.  相似文献   
900.
Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals.  相似文献   
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