Brain-stimulation intensity, rate of self-stimulation, and reinforcement strength: an analysis through chaining

Reinforcement strengths of different intensities of brain stimulation were assessed by means of a two-member behavioral chain. A variable interval schedule of 30 sec was the first-member, and five lever presses, each rewarded with stimulation, was the second. It was found that response rate on the VI schedule continued to increase beyond the intensity value which produced peak rate on the second-member, self-stimulation lever. It was concluded (1) that brain-stimulation reinforcement strength cannot be assessed adequately by means of self-stimulation rate, and (2) the chaining technique employed in the present experiment appears promising as an analytical tool in brain-stimulation research. Finally, some aspects of the data suggested a fatigue or stimulation-adaptation phenomenon.     

Exteroceptive control of response under delayed reinforcement

Three white rats, after 50 continuous reinforcements, were exposed successively, under dim illumination, to reinforcement delays of 1, 3, 5, 7.5, 10, 15, and 20 sec, with prolonged training at the 20-sec level. Behavior was maintained at each level, and an increase in interval was accompanied by an increase in post-reinforcement pause. Subsequently, under both 20- and 30-sec delays, the animals were tested during half of each daily session to determine the effect of introducing darkness during each delay interval. The result of this stimulus “support” was to regularize and increase response rate for each animal at both interval values.     

Stimulus generalization and the response-reinforcement contingency

Generalization gradients along a line-tilt continuum were obtained from groups of pigeons that had been trained to peck a key on different schedules of reinforcement. In Exp. I, gradients following training on a differential-reinforcement-of-low-rate (DRL) schedule proved to be much flatter than gradients following the usual 1-min variable interval (VI) training. In Exp. II, the value of the VI schedule itself was parametrically studied; Ss trained on long VI schedules (e.g., 4-min) produced much flatter gradients than Ss trained on short VI schedules (30-sec; 1-min). The results were interpreted mainly in terms of the relative control exerted by internal, proprioceptive cues on the different reinforcement schedules. Several implications of the results for other problems in the field of stimulus generalization are discussed.     

Late Adolescents' Experiences With and Attitudes Toward Videogames1

A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.     

初级指挥官人格类型与PM领导行为类型有效性的关系

通过对陆军初级指挥官人格心理类型与领导行为有效性的心理学研究 ,探讨个人的领导潜能、人格心理类型对领导行为有效性的影响。研究发现 :1方差分析表明 ,具有不同领导行为的指挥官在人格维度上存在明显的统计学差异。提示了指挥官的领导行为取向与人格因素有密切的关系。2卡方分析结果也表明 ,PM型行为的军官在其人格特征上具有“ESTJ”组合特征 ,而 pm型的军官则正好相反 ;另外 ,pm型的军官在成就动机上获得高分的人数最少。3系统聚类分析显示 ,“成就动机”、“感觉”和“判断”三种人格因素与军事指挥官完成整体领导职能有着更为密切的关系。     

追踪作业中几种心理负荷评估指标敏感性的研究

本研究在模拟追踪作业情境下 ,对主任务绩效测定、主观评定和若干生理测量在心理负荷评估中的敏感性进行了实验。实验采用重复测量的被试者内设计 ,2 0名被试 (男女各半 )在六档负荷下分别从事五分钟追踪作业。所选用的指标有追踪作业平均误差距离、追踪警告次数、主观负荷评定、心率、心率变异和血压。结果发现 :1主任务绩效在评估追踪作业心理负荷中具有最高的敏感性 ,主观评定次之 ,心率变化率和心率变异变化率也随负荷变化 ,血压指标随负荷变化的趋势不明显 ;2除血压指标外 ,其余各指标之间均存在明显的相关 ,这提示它们在评估追踪作业心理负荷中具有较大的可靠性。     

How Americans Perceive Foreign Policy Threats: A Magnitude Scaling Analysis

This paper evaluates three hypotheses about the structure of threat perceptions in the post-Cold War era: the replacement of a military conception of threat by an economic one; fluidity in threat perceptions because of an absence of a polestar nation; and Huntington's clash of civilizations theory. Using psychophysical magnitude measures of threat perception, these findings provide no support for the notion that threats are perceived economically. There is limited support for the theory that threat perceptions are unstable; most countries are clustered around a core of weakly hostile or friendly perceptions, which is suggestive of instability. At the same time, however, there does appear to be stability in perceptions of strong friends and enemies. The hypothesis best supported by these data is Huntington's theory that culture determines threat perceptions. In this study, not a single Western country is perceived as hostile, and all nations that do receive hostile scores are non-Western.