Stimulus control of responding by response-reinforcer temporal contiguity

The stimulus properties of brief disruptions in response-reinforcer temporal contiguity were investigated using a discrete trial conditional discrimination procedure. Key pecking (nondelay) or key pecking followed by a brief interval of nonpecking (delay) in the sample component produced a stimulus change (choice component). Pecks in the choice component to one of two alternatives resulted in food or blackout, conditional upon which response requirement was met in producing the choice component. A baseline condition, in which key pecking always produced the choice component and correct choices were arranged randomly, alternated with experimental conditions that included nondelay and delay values of either 0.2, 0.5, or 1.0 sec between the last key peck and the initiation of the choice component. All subjects accurately discriminated brief temporal delays between a response and stimulus change, with choice accuracy increasing for three of four subjects as the temporal disruption in contiguity increase. Implications of the research for the study of delayed reinforcement, response-independent reinforcement, and the discrimination of causality are discussed.     

《管子》与汉初法制重构

《管予》渊源于齐文化,法制思想以礼、法并重为特色,齐用之而为东方大国;秦用商、韩之法迅速强大并统一六国,但秦法严苛激进,任法而废礼,致秦二世而亡。汉承秦之弊,在历史与现实中寻求适合自己发展的道路,于偶然,也是必然中选择了礼法并重的《管子》法制思想作为治国方略,史称黄老政治,使国家逐步实现了稳定与繁荣,并开创了二千多年的秦汉制度。     

Children's affective,behavioral, and cognitive responses to social comparison

Relative outcomes in social commerce with peers are potent determinants of cognitions and behavior in young children. Although there has been considerable attention given to the behavioral consequences of social comparisons following the receipt of rewards, there has been less concern with cognitive or affective consequences. Additionally, little is known about the accrued effects of multiple social comparison experiences that may be consistent or inconsistent with one another. In the present study, young children received a constant level of reward but the amount they saw a peer receive was varied. There were two sequences of reward distribution, and in a given sequence children received either the same number of rewards as the peer (=), more (+), or fewer (?). In a 3 × 3 factorial design all possible combinations occurred. A negative inequality in reward distribution, no matter where it fell in a sequence, made children sad and inclined children to distribute fewer rewards to peers. When a sequence contained an initial experience of positive inequality, children decreased subsequent levels of self-reward. Experiencing a comparison that revealed a negative inequality in reward distribution also disrupted children's accuracy in appraising the overall distribution of rewards: even when an initial negative inequality was completely offset by an equivalent experience of positive inequality, children inaccurately concluded that they had received fewer rewards than their peers.     

Stereo disparity facilitates view generalization during shape recognition for solid multipart objects

Current theories of object recognition in human vision make different predictions about whether the recognition of complex, multipart objects should be influenced by shape information about surface depth orientation and curvature derived from stereo disparity. We examined this issue in five experiments using a recognition memory paradigm in which observers (N = 134) memorized and then discriminated sets of 3D novel objects at trained and untrained viewpoints under either mono or stereo viewing conditions. In order to explore the conditions under which stereo-defined shape information contributes to object recognition we systematically varied the difficulty of view generalization by increasing the angular disparity between trained and untrained views. In one series of experiments, objects were presented from either previously trained views or untrained views rotated (15°, 30°, or 60°) along the same plane. In separate experiments we examined whether view generalization effects interacted with the vertical or horizontal plane of object rotation across 40° viewpoint changes. The results showed robust viewpoint-dependent performance costs: Observers were more efficient in recognizing learned objects from trained than from untrained views, and recognition was worse for extrapolated than for interpolated untrained views. We also found that performance was enhanced by stereo viewing but only at larger angular disparities between trained and untrained views. These findings show that object recognition is not based solely on 2D image information but that it can be facilitated by shape information derived from stereo disparity.     

“自杀”：一个重要的伦理问题

自杀现已成为人类死亡十大原因之一 ,而且呈现出低龄化的趋势 ,越来越引起社会的关注。因而 ,从政治、经济、社会、疾病、文化等多视角来寻找自杀的外部原因 ,对探究这个重要的伦理问题是有益的。     

Effects of circular motion on judgment of rotation direction and depth order in visual motion

Abstract:  The rotation direction and depth order of a rotating sphere consisting of random dots often reverses while it is viewed under orthographic projection. However, if a short viewing distance is simulated under perspective projection, the correct rotation direction can be perceived. There are two motion cues for the rotation direction and depth order. One is the speed cue; points with higher velocities are closer to the observer. The other is the vertical motion cue; vertical motion is induced when the dots recede from or approach the observer. It was examined whether circular motion, which does not have any depth information but induces vertical velocities, masks the vertical motion cue. In Experiment 1, the effects of circular motion on the judgment of the rotation direction of a rotating sphere were examined. The magnitude of the two cues (the speed cue and the vertical velocity cue) as well as the angular speed of circular motion was varied. It was found that the performance improved as the vertical velocity increased and that the speed cue had slight effects on the judgment of the rotation direction. It was also found that the performance worsened as the angular speed of the circular motion was increased. In Experiment 2, the effects of circular motion on depth judgment of a rotating half sphere were investigated. The performance worsened as the angular speed of the circular motion increased, as in Experiment 1. These results suggest that the visual system cannot compensate perfectly for circular motion for the judgment of the rotation direction and depth order.     

POLITICS: Automated ideological reasoning

POLITICS is a system of computer programs which simulates humans in comprehending and responding to world events from a given political or ideological perspective. The primary theoretical motivations were: (1) the implemention of a functional system which applies the knowledge structures of Schank and Abelson (1977) to the domain of simulating political belief systems; (2) the development of a tentative theory of intentional goal conflicts and counterplanning. Secondary goals of the POLITICS project include developing a representation for belief systems, investigating cognitive processes such as goal-directed inferencing, and the integration of several types of knowledge representations into a functional system.     

Mediated conditioning versus retrospective revaluation in humans: The influence of physical and functional similarity of cues

Two experiments assessed whether similarity between the two elements of a compound would influence the degree of mediated extinction versus recovery from overshadowing in human causal judgements. In both Experiments 1 and 2, we assessed the influence of extinguishing one element of a two-element compound on judgements about the other element. In Experiment 1 we manipulated the physical similarity of the two elements of the compound; in Experiment 2, we used equivalence and distinctiveness pretraining in order to vary their functional similarity. We found that these procedures influenced mediated extinction and recovery from overshadowing as a function of both physical and acquired similarity and distinctiveness, respectively. The implications of these results for previously reported differences between humans and nonprimate animals are discussed.