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871.
Influence of seasonally adjusted exposure to cold and darkness on cognitive performance in circumpolar residents 总被引:2,自引:0,他引:2
Palinkas LA Mäkinen TM Pääkkönen T Rintamäki H Leppäluoto J Hassi J 《Scandinavian journal of psychology》2005,46(3):239-246
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. 相似文献
872.
Australian brush-turkeys, Alectura lathami, are birds with an unusual life history: The young receive no parental care and first encounter conspecifics at an unpredictable age. Brush-turkey chicks that were 3-4 days old were presented with a robot model that appeared to feed from a distinctively colored dish. In control training trials, chicks saw a robot standing next to a different dish and scanning from side to side. Chicks expressed a strong tendency to feed from dishes of the type indicated by the pecking robot, but this effect proved ephemeral. Brush-turkeys hence appear to show no social learning under conditions that inculcate stable preferences in other galliforms such as chickens, suggesting that life history plays an important role in the evolution of learning. 相似文献
873.
Lack of the metabotropic glutamate receptor subtype 7 selectively modulates Theta rhythm and working memory 下载免费PDF全文
Hölscher C Schmid S Pilz PK Sansig G van der Putten H Plappert CF 《Learning & memory (Cold Spring Harbor, N.Y.)》2005,12(5):450-455
Metabotropic glutamate receptors (mGluRs) are known to play a role in synaptic plasticity and learning. We have previously shown that mGluR7 deletion in mice produces a selective working memory (WM) impairment, while other types of memory such as reference memory remain unaffected. Since WM has been associated with Theta activity (6-12 Hz) in EEGs, and since EEG abnormalities have been observed in these mice before, we studied the effect of mGluR7 gene ablation on EEG activity in the hippocampus, in particular in the Theta range, during performance of a WM task. In an eight-arm maze with four arms baited, mGluR7 knock-out (KO) and wild-type mice committed the same number of reference memory errors, whereas KOs committed more WM errors. While performing the task, KO mice showed substantially higher Theta amplitudes, and the ratio of Theta to overall EEG power was much increased. No change was seen in the Delta (0-5 Hz), or Gamma (30-40 Hz) EEG bands compared with controls. When recording EEGs during periods of rest in the home cages, no difference was seen between groups. These findings suggest that mGluR7 is important for modulation and control of Theta activity. Since only WM was affected, and only the Theta range of EEG activity was altered, these results show a correlation between Theta rhythm and WM performance, and therefore support the concept that Theta activity in the hippocampus is involved in WM storage. 相似文献
874.
L. L. Thurstone's (1927) model provides a powerful framework for modeling individual differences in choice behavior. An overview of Thurstonian models for comparative data is provided, including the classical Case V and Case III models as well as more general choice models with unrestricted and factor-analytic covariance structures. A flow chart summarizes the model selection process. The authors show how to embed these models within a more familiar structural equation modeling (SEM) framework. The different special cases of Thurstone's model can be estimated with a popular SEM statistical package, including factor analysis models for paired comparisons and rankings. Only minor modifications are needed to accommodate both types of data. As a result, complex models for comparative judgments can be both estimated and tested efficiently. 相似文献
875.
Carlbring P Nilsson-Ihrfelt E Waara J Kollenstam C Buhrman M Kaldo V Söderberg M Ekselius L Andersson G 《Behaviour research and therapy》2005,43(10):1321-1333
A randomized trial was conducted comparing 10 individual weekly sessions of cognitive behaviour therapy for panic disorder (PD) with or without agoraphobia with a 10-module self-help program on the Internet. After confirming the PD diagnosis with an in-person structured clinical interview (SCID) 49 participants were randomized. Overall, the results suggest that Internet-administered self-help plus minimal therapist contact via e-mail can be equally effective as traditional individual cognitive behaviour therapy. Composite within-group effect sizes were high in both groups, while the between-group effect size was small (Cohen's d=16). One-year follow-up confirmed the results, with a within-group effect size of Cohen's d=0.80 for the Internet group and d=0.93 for the live group. The results from this study generally provide evidence to support the continued use and development of Internet-distributed self-help programs. 相似文献
876.
Hölter R 《The Journal of analytical psychology》2005,50(4):521-537
Traumatic experiences of violence like those that were brought about by the communist regime of the former German Democratic Republic (GDR) are still present as if they happened yesterday, causing severe disadvantages in everyday life even after all those years. Consequently, in cases of extreme traumatization induced by political imprisonment, persecution and applied psychological methods of disintegration, regressive processes take place which corrode the ego. The breakdown of cathexis, i.e., the failure of empathic connection at the time of the trauma, is the strongest characteristic of severe traumatization. As a result of this destruction for the traumatized there is an inability to keep upright an inner empathic, emotional connection. As we try to grasp, from a Jungian point of view, the psychodynamics of severe traumatization, we can speak of a powerful pathogenous complex, which I call the 'Prometheus-complex'. Gustav Bovensiepen speaks of this complex as a sub-network, a limited fragment of the matrix of all internalized experiences, consisting of internal working models, feelings and patterns of anticipation which interact mutually. The human being, captured in such isolation and paralysis of the mind, can find himself 'in the therapist' on a mental level. 相似文献
877.
Healthy subjects adjust their grip force economically to the weight of a hand-held object. In addition, inertial loads, which arise from arm movements with the grasped object, are anticipated by parallel grip force modulations. Internal forward models have been proposed to predict the consequences of voluntary movements. Anesthesia of the fingers impairs grip force economy but the feedforward character of the grip force/load coupling is preserved. To further analyze the role of sensory input for internal forward models and to characterize the consequences of central nervous system damage for anticipatory grip force control, we measured grip force behavior in neurological patients. We tested a group of stroke patients with varying degrees of impaired fine motor control and sensory loss, a single patient with complete and permanent differentation from all tactile and proprioceptive input, and a group of patients with amyotrophic lateral sclerosis (ALS) that exclusively impairs the motor system without affecting sensory modalities. Increased grip forces were a common finding in all patients. Sensory deficits were a strong but not the only predictor of impaired grip force economy. The feedforward mode of grip force control was typically preserved in the stroke patients despite their central sensory deficits, but was severely disturbed in the patient with peripheral sensory deafferentation and in a minority of stroke patients. Moderate deficits of feedforward control were also obvious in ALS patients. Thus, the function of the internal forward model and the precision of grip force production may depend on a complex anatomical and functional network of sensory and motor structures and their interaction in time and space. 相似文献
878.
Research on scene perception indicates that viewers often fail to detect large changes to scene regions when these changes occur during a visual disruption such as a saccade or a movie cut. In two experiments, we examined whether this relative inability to detect changes would produce systematic biases in event memory. In Experiment 1, participants decided whether two successively presented images were the same or different, followed by a memory task, in which they recalled the content of the viewed scene. In Experiment 2, participants viewed a short video, in which an actor carried out a series of daily activities, and central scenes' attributes were changed during a movie cut. A high degree of change blindness was observed in both experiments, and these effects were related to scene complexity (Experiment 1) and level of retrieval support (Experiment 2). Most important, participants reported the changed, rather than the initial, event attributes following a failure in change detection. These findings suggest that attentional limitations during encoding contribute to biases in episodic memory. 相似文献
879.
Using lexical decision, the effects of primes of different length on spoken word recognition were evaluated in three partial repetition priming experiments. Prime length was determined via gating (Experiments 1a and 2a). It was shorter than, equivalent to, or longer than the recognition point (RP), or a complete word. In Experiments 1b and 1c, priming increased with prime length and was independent of reaction time. The influence of sensory information following the RP was investigated in Experiment 2b. Latencies decreased with increasing prime length, but priming decreased only for complete words. RP and complete words have a special status. Lexical representations are activated to different degrees at the RP and at word offset. 相似文献
880.
Prenatal androgens and gender-typed behavior: a study of girls with mild and severe forms of congenital adrenal hyperplasia 总被引:1,自引:0,他引:1
Gender-typed behaviors and interests were investigated in 26 girls, aged 2-10 years, affected with congenital adrenal hyperplasia (CAH) and in 26 unaffected girls matched for age. Girls with CAH were more interested in masculine toys and less interested in feminine toys and were more likely to report having male playmates and to wish for masculine careers. Parents of girls with CAH rated their daughters' behaviors as more boylike than did parents of unaffected girls. A relation was found between disease severity and behavior indicating that more severely affected CAH girls were more interested in masculine toys and careers. No parental influence could be demonstrated on play behavior, nor did the comparison of parents' ratings of wished for behavior versus perceived behavior in their daughters indicate an effect of parental expectations. The results are interpreted as supporting a biological contribution to differences in play behavior between girls with and without CAH. 相似文献