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961.
Gamma-hydroxybutyric acid (GHB) is a drug with abuse potential, popularly known as "liquid ecstasy". It is an endogenous compound of the mammalian brain which satisfies many of the criteria for consideration as a neurotransmitter or neuromodulator. In this study, the effects of acute administration of GHB (40, 80 and 120 mg/kg, ip) on anxiety, tested in the light/dark box, were examined in male mice of the OF.1 strain. Likewise, we compared the behavioural profile of GHB with that induced by mCPP (1 mg/kg, ip), a compound with known anxiogenic actions. GHB-treated mice spent notably less time in the lit area (40 and 80 mg/kg) and more time in the dark area (all doses), whereas the total number of 'rearings', transitions and latency were significantly reduced. A very similar behavioural profile was observed in mCPP-treated animals. Overall, these findings indicate that GHB exhibits anxiogenic-like properties in male mice. It is suggested that the anxiogenic effects of GHB could be related to its ability to modulate GABA and/or dopaminergic receptors.  相似文献   
962.
Cognitive dysfunction has been widely studied in multiple sclerosis (MS), however decision-making has been less investigated. The current study examined the decision-making processes of patients with multiple sclerosis (MS) using a computerized version of the Iowa Gambling Task (IGT). This task was applied to 18 patients with clinically diagnosed MS and 18 healthy control subjects matched for age, sex, and years of education. The results showed that IGT scores differ significantly between patients with MS and the healthy control subjects: the patients with MS made significantly less advantageous decisions than the controls in the IGT. Possible causes of impaired decision-making in multiple sclerosis are discussed.  相似文献   
963.
It has been proposed that causal power (defined as the probability with which a candidate cause would produce an effect in the absence of any other background causes) can be intuitively computed from cause-effect covariation information. Estimation of power is assumed to require a special type of counterfactual probe question, worded to remove potential sources of ambiguity. The present study analyzes the adequacy of such questions to evoke normative causal power estimation. The authors report that judgments to counterfactual probes do not conform to causal power and that they strongly depend on both the probe question wording and the way that covariation information is presented. The data are parsimoniously accounted for by an alternative model of causal judgment, the Evidence Integration rule.  相似文献   
964.
何琛  解蕴慧  马力 《心理科学》2012,35(4):968-972
本研究探索了压力偏好和任务类型在拖延行为对绩效产生作用过程中的调节作用。用问卷调查的方法对155人进行调查。结果发现:相比偏好压力者,厌恶压力者的工作绩效更容易受到拖延行为的影响;对于复杂任务,拖延对偏好压力者的绩效影响显著低于对厌恶压力者;而对于简单任务,两种类型人的绩效的差别并不明显。结论是,偏好压力者能够减弱拖延行为对其工作绩效的影响,尤其对于复杂任务,这种影响更加明显。  相似文献   
965.
本文认为<老子指归>为西汉严君平原著,汉唐时期严君平在蜀中一直倍受尊崇,其书对<老子想尔注>产生了重要影响,两者的密切关系从一个侧面说明<老子想尔注>出于三张之手.  相似文献   
966.
Perceiving an event requires the integration of its features across numerous brain maps and modules. Visual object perception is thought to be mediated by a ventral processing stream running from occipital to inferotemporal cortex, whereas most spatial processing and action control is attributed to the dorsal stream connecting occipital, parietal, and frontal cortex. Here we show that integration operates not only on ventral features and objects, such as faces and houses, but also across ventral and dorsal pathways, binding faces and houses to motion and manual action. Furthermore, these bindings seem to persist over time, as they influenced performance on future task-relevant visual stimuli. This is reflected by longer reaction times for repeating one, but alternating other features in a sequence, compared to complete repetition or alternation of features. Our findings are inconsistent with the notion that the dorsal stream is operating exclusively online and has no access to memory.  相似文献   
967.
968.
The main aim of this work was to show the impact of preexisting causal beliefs on causal induction from cause-effect co-occurrence information, when several cues compete with each other for predicting the same effect. Two different causal scenarios -- one social (a), the other medical (b) -- were used to check the generality of the effects. In Experiments 1a and 1b, participants were provided information on the co-occurrence of a two-cause compound and an effect, but not about the potential relationship between each cause by its own and the effect. As expected, prior beliefs -- induced by means of instructions -- strongly modulated the causal strength assigned to each element of the compound. In Experiments 2a and 2b, covariation evidence was provided, not only about the predictive value of the two-cause compound, but also about one of the elements of the compound. When this evidence was available, prior beliefs had less impact on judgments, and these were mostly guided by the relative predictive value of the cue. These results demonstrate the involvement of inferential integrative mechanisms in the generation of causal knowledge and show that single covariation detection mechanisms -- either rule-based or associative -- are insufficient to account for human causal judgment. At the same time, the fact that the power of new covariational evidence to change prior beliefs depended on the availability of information on the relative (conditional) predictive value of the target candidate cause suggests that causal knowledge derived from information on causal mechanisms and from covariation probably share a common representational basis.  相似文献   
969.
The relation between parenting styles and adolescent outcomes was analyzed in a sample of 1,198 15-18-year-old Brazilians. The adolescents were classified into 1 of 4 groups (Authoritative, Authoritarian, Indulgent, and Neglectful) on the basis of their own ratings of their parents on two dimensions: Acceptance/ Involvement and Strictness/Imposition. The adolescents were then contrasted along two different outcomes: (1) priority given to Schwartz Self-transcendence and Conservation values, and (2) level of Self-esteem (appraised in 5 domains: Academic, Social, Emotional, Family, and Physical). Results showed that Authoritative and Indulgent parenting is associated with the highest internalization of Self-Transcendence and Conservation values of teenagers, whereas Authoritarian parenting is associated with the lowest. On the other hand, adolescents with Indulgent parents have equal or higher levels of Self-esteem than adolescents with Authoritative parents, while adolescents raised in Authoritarian and Neglectful homes have the lowest scores in Self-Esteem.  相似文献   
970.
The most commonly employed item selection rule in a computerized adaptive test (CAT) is that of selecting the item with the maximum Fisher information for the estimated trait level. This means a highly unbalanced distribution of item‐exposure rates, a high overlap rate among examinees and, for item bank management, strong pressure to replace items with a high discrimination parameter in the bank. An alternative for mitigating these problems involves, at the beginning of the test, basing item selection mainly on randomness. As the test progresses, the weight of information in the selection increases. In the present work we study, for two selection rules, the progressive methods ( Revuelta & Ponsoda, 1998 ) and the proportional method ( Segall, 2004a ), different functions that define the weight of the random component according to the position in the test of the item to be administered. The functions were tested in simulated item banks and in an operative bank. We found that both the progressive and the proportional methods tolerate a high weight of the random component with minimal or zero loss of accuracy, while bank security and maintenance are improved.  相似文献   
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