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111.
Pigeons were trained to discriminate 5 mg/kg pentobarbital from saline under concurrent variable-ratio (VR) VR schedules, in which responses on the pentobarbital-biased lever were reinforced under the VR schedule with the smaller response requirements when pentobarbital was given before the session, and responses on the saline-biased key were reinforced under the VR schedule with the larger response requirements. When saline was administered before the session, the reinforcement contingencies associated with the two response keys were reversed. When responding stabilized under concurrent VR 20 VR 30, concurrent VR 10 VR 40, or concurrent VR 5 VR 50 schedules, pigeons responded almost exclusively on the key on which fewer responses were required to produce the reinforcer. When other doses of pentobarbital and other drugs were substituted for the training dose, low doses of all drugs produced responding on the saline-biased key. Higher doses of pentobarbital and chlordiazepoxide produced responding only on the pentobarbital-biased key, whereas higher doses of ethanol and phencyclidine produced responding only on this key less often. d-Amphetamine produced responding primarily on the saline-biased key. When drugs generalized to pentobarbital, the shape of the generalization curve under concurrent VR VR schedules was more often graded than quantal in shape. Thus, drug discrimination can be established under concurrent VR VR schedules, but the shapes of drug-discrimination dose-response curves under concurrent VR VR schedules more closely resemble those seen under interval schedules than those seen under fixed-ratio schedules. Graded dose-response curves under concurrent VR VR schedules may relate to probability matching and difficulty in discriminating differences in reinforcement frequency. 相似文献
112.
The goal of this study was to test the response styles theory of depression in a sample of 3rd- and 7th-grade children. In addition, we examined whether the relationship between rumination and increases in depressive symptoms is mediated by hopelessness and low self-esteem. The procedure involved an initial assessment in which depressive symptoms, response styles, hopelessness, and self-esteem were assessed. The procedure also involved a follow-up assessment, 6 weeks later, in which depressive symptoms, hopelessness, and self-esteem were reassessed. Children with a ruminative response style exhibited increases in depressive symptoms over the 6-week period. In addition, the relationship between rumination and increases in depressive symptoms was mediated by both hopelessness and low self-esteem. Last, contrary to our hypotheses, neither distraction nor problem-solving response styles predicted decreases in depressive symptoms over the course of the study. 相似文献
113.
We examine the hypothesis that the efficiency of executive control processes is less stable over time in older than younger adults. An age-related decrease in the efficiency of executive control should result in an increase in performance variability in task conditions requiring the recruitment of executive control processes and not in task conditions requiring minimal involvement of executive control. Performance variability was similar for younger and older adults in task conditions requiring minimal executive control and greater for older than younger adults in task conditions requiring executive control. These and other data are consistent with the proposal that aging is associated with a decrease in the stability of executive control over time. 相似文献
114.
Nersesyan AK 《Science and engineering ethics》2002,8(3):291-293
The author describes problems facing Armenia in reorganization of the structure of science in the post-socialist era with
the aim of utilizing limited state resources more efficiently by reducing the number of separate scientific institutes, concentrating
on essential core subjects required by the nation and encouraging all other projects to compete in the international arena
for grant sponsorship.
An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance
in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002. 相似文献
115.
中国大学生的记忆的自我参照效应 总被引:15,自引:1,他引:14
记忆的自我参照效应是指记忆材料与自我相联系时的记忆效果优于其它编码条件的现象,这种优势主要体现在以回忆经验为特征的R反应(“记得”)上。西方一些研究表明,自我参照的记忆成绩优于参照母亲的记忆。本研究以中国大学生为被试,得到参照父亲和母亲的记忆与自我参照有同样好的成绩,显著优于参照名人的记忆,并且父母之间无差异。这支持了独立型/依赖型自我概念模型中的东方文化下的自我概念包括父母的观点。 相似文献
116.
Five adolescents with autism, 5 adult control participants, and 4 child controls received rewards for varying their sequences of responses while playing a computer game. In preceding and following phases, rewards were provided at approximately the same rate but were independent of variability. The most important finding was that, when reinforced, variability increased significantly in all groups. Reinforced variability could provide the necessary behavioral substrate for individuals with autism to learn new responses. 相似文献
117.
Hyperactivity has attracted a large amount of research interest in recent years. Here we review developments in genetic research and in research testing psychological theories of the condition. Family, adoptee and twin studies indicate a strong role for genetic factors in the etiology of hyperactivity. Evidence is emerging also from molecular genetic studies, implicating specific genes that may be involved. At the level of cognitive functioning, a divided, focused or sustained attention deficit does not seem to be a core deficit in hyperactivity. Although children with hyperactivity often perform poorly on certain executive function tasks, there is disagreement about the interpretation of these findings. The association reported in some studies between a slow inhibitory process and hyperactivity may reflect a generally slow, variable in speed and inaccurate pattern of responding. Hypotheses about psychological mechanisms such as state regulation or delay aversion provide alternative, and particularly encouraging, interpretations of the findings. We discuss the possible integration of the two lines of research—those of genetic research and research on psychological mechanisms. 相似文献
118.
Sealey DM Sumpter CE Temple W Foster TM 《Journal of the experimental analysis of behavior》2005,84(1):19-35
To examine the effects on concurrent performance of independent manipulations of response-unit duration and number, 6 hens were exposed to concurrent second-order schedules of reinforcement. Each first-order operant unit required completion of a fixed-ratio schedule within the time specified by a fixed-interval schedule, with one further response completing the fixed-interval schedule. The fixed-ratio and fixed-interval requirements comprising the first-order operant units were systematically and independently varied under three pairs of concurrent variable-interval schedules to produce differences in the first-order response and duration requirements (response and duration differentials). These manipulations produced consistent changes in response, time, and operant-unit biases. A 1:4 response differential biased the time and operant-unit measures towards the smaller fixed ratio, but to a degree less than the imposed response differential. The response-based biases favored the larger fixed ratio. Duration differentials of 4:1 and 8:1 biased the response and operant-unit measures towards the shorter fixed interval, again less than the imposed duration differential, but the time biases remained close to zero. Both sorts of differentials acted to bias operant-unit completions more systematically than the other measures, but undermatching to the differentials occurred. The undermatching appears to have arisen from a pattern of fix and sample (in which visits to the less preferred alternative involved only a single completed operant unit) under combinations of unequal operant-unit requirements and reinforcer rates. The response and time bias measures appeared to arise as by-products of the changes in operant-unit completions. 相似文献
119.
Kalenscher T Güntürkün O Calabrese P Gehlen W Kalt T Diekamp B 《Journal of the experimental analysis of behavior》2005,84(3):521-535
Working memory, the ability to temporarily retain task-relevant information across a delay, is frequently investigated using delayed matching-to-sample (DMTS) or delayed Go/No-Go tasks (DGNG). In DMTS tasks, sample cues instruct the animal which type of response has to be executed at the end of a delay. Typically, performance decreases with increasing delay duration, indicating that working memory fades across a delay. However, no such performance decrease has been found when the sample cues exist of present vs. absent stimuli, suggesting that pigeons do not rely on working memory, but seem to respond by default in those trials. We trained 3 pigeons in a DGNG task and found a similar default response pattern: The diverging slopes of the retention functions on correct Go and No-Go trials suggested that pigeons by default omitted their response following No-Go stimuli, but actively retained task-relevant information across the delay for successful responses on Go trials. We conducted single-cell recordings in the avian nidopallium caudolaterale, a structure comparable to the mammalian prefrontal cortex. On Go trials, many neurons displayed sustained elevated activity during the delay preceding the response, replicating previous findings and suggesting that task-relevant information was neurally represented and maintained across the delay. However, the same units did not show enhanced delay activity preceding correct response suppressions in No-Go trials. This activation-inactivation pattern presumably constitutes a neural correlate of the default response strategy observed in the DGNG task. 相似文献
120.
Edmund?R.?ThompsonEmail author Florence?T.?T.?Phua 《Journal of business and psychology》2005,19(4):541-554
The majority of scholarly management studies are based on self-report surveys. Consequently, the need to control for social desirability response is important, although few management studies in fact include the use of relevant scales commonly incorporated in psychology research. The full Marlowe–Crowne scale is disaffectingly long for senior-manager sample usage, so one of its short forms is more practical. However, the reliability of the most popular of these, the Strahan–Gerbasi scale, has not been tested with senior-manager samples. This study tests the scale amongst several senior-manager samples and finds it consistently lacks adequate reliability and unidimensionality. 相似文献