Acute and chronic effects of cocaine on the spontaneous behavior of pigeons

The present experiment examined the effects of acute and daily cocaine on spontaneous behavior patterns of pigeons. After determining the acute effects of a range of doses, 9 pigeons were divided into three groups that received one of three doses of cocaine daily, either 1.0, 3.0, or 10.0 mg/kg cocaine. Measures were taken of spontaneous locomotion, pecking, preening, and emesis. Under daily administration, cocaine induced consistent and substantial enhancements of its locomotor effects in all 9 pigeons, consistent with the phenomenon of locomotor sensitization. The maximum locomotor output did not differ according to the size of the daily dose. Locomotion was not elevated following tests of the saline vehicle, suggesting the effect was due to cocaine, not to a change in baseline or reactivity to the injection procedure. Cocaine dose‐dependently decreased preening when given acutely, and those effects were not altered by repeated cocaine administration. Pecking occurred at very low rates and was unresponsive to cocaine treatment. Cocaine‐induced emesis showed a dose‐dependent increase under initial tests with cocaine, and those effects were attenuated following daily exposure. In a final condition, cocaine was replaced with daily saline for 30 days to assess the persistence cocaine‐related increases in locomotion. Approximately half of the pigeons continued to show enhanced effects even after 30 days without cocaine, so although persistence was obtained, it showed marked intersubject variability. The data indicate that the effects of repeated cocaine administration on the behavior of pigeons shows parallels with many effects commonly reported with rodents (i.e., increased locomotion following repeated treatment, decrease in preening or grooming, persistence following drug withdrawal).     

Evaluative conditioning of high-novelty stimuli does not seem to be based on an automatic form of associative learning

Evaluative conditioning (EC) refers to the change in valence of initially neutral stimuli (conditioned stimuli, or CSs) as a result of their pairing with positive or negative stimuli (unconditioned stimuli, or USs). EC is critical to dual-attitudes models as it is often presented as an evaluative effect that results from a purely automatic form of associative learning. Although evidence suggests that EC does not occur without contingency awareness, Ruys, and Stapel (2009) recently argued that contingency awareness is unnecessary for high-novelty stimuli. Researchers may thus be tempted to conclude that EC rests on an automatic form of associative learning, at least for CSs associated with little prior evaluative knowledge. Taking issue with this claim, the present study reveals that EC of high-novelty stimuli is dependent on attentional resources. The role of contingency awareness in EC of high-novelty stimuli is also discussed.     

Relationship between a history of consistent maternal employment and depression in young adults

Research on the correlates of maternal employment has yielded inconsistent results. In this study, 79 male and 120 female undergraduates with mothers who had been employed from the students' infancy through their adolescence scored higher on the Beck Depression Inventory-II than those whose mothers had not been employed. This relationship between children's depressive symptoms and mothers' employment history was not evident among young adults whose mothers' employment was perceived to be financially unnecessary.     

The temporal contiguity effect predicts episodic memory performance

One way to study the associative processes at work during episodic memory is to examine the order of participant responses, which reveal the strong tendency to transition between temporally contiguous or semantically proximal items on the study list. Here, we assessed the correlation between participants’ recall performance and their use of semantic and temporal associations to guide retrieval across nine delayed free recall studies. The size of the participants’ temporal contiguity effects predicted their recall performance. When interpreted in terms of two models of episodic memory, these results suggest that participants who more effectively form and retrieve associations between items that occur nearby in time perform better on episodic recall tasks. Sample code may be downloaded as a supplement for this article from http://mc.psychonomic-journals.org/content/ supplemental.     

THE DEVELOPMENT OF LOCKEAN ABSTRACTION

In this work I argue that Descartes was not a trialist by showing that the main tenets of trialist interpretations of Descartes's theory of substance are either not supported by the text or are not sufficient for establishing the trialist interpretation.     

Eastern Europe 1997-2000: A Review of Church Life

A decade after the collapse of communist rule, Christian life in Eastern Europe continues to be a complex mixture of satisfaction and disappointment. This survey of the last four years illustrates the recent successes and failures, and sets out to highlight the many challenges which still await effective responses.     

Separation of Religion and State and Secularism in Theory and in Practice

Abstract

This study examines whether states follow the religion policies they declare in their constitutions. It identifies four types of policies which officially seek to limit religion's role in government: absolute separation of religion and state (SRAS); neutral political concern; exclusion of ideals; and secularism–laicism. I determine whether states follow these policies using the religion and state (RAS) dataset and compare this to constitutional declarations that the state is secular and declarations of separation of religion and state. The results show that a majority of states which make both types of declaration do not follow these policies based on any of the four standards used in this study. However, the presence and wording of these clauses are correlated with state religion policy.     

Evidence of the Psychometric Integrity of the Creative Personality Scale using Item Response Theory Models

Gough’s Creative Personality Scale (CPS) has been very widely used to assess creative personality characteristics, and many researchers have argued that it is associated with strong reliability and validity evidence. However, findings vary considerably across the samples used in each study, suggesting that an analysis using the item response theory framework would provide more useful evidence of the instrument’s psychometric integrity. Results suggest that the CPS is multidimensional, and some items have low discrimination indices. Additionally, significant correlations between participants’ trait estimates (i.e., estimated creative personality) and their engagement in a range of creative activities indicate that the CPS is associated with convincing evidence of criterion-related validity.     

The Role of Concurrent Feedback in Learning to Walk Through Sliding Doors

Concurrent feedback is defined as information about performance given to participants during the execution of an action. This article investigates whether concurrent feedback is beneficial or detrimental to the learning of an ecologically relevant task. Eighteen participants were asked to walk through a virtual corridor and they practiced over 1110 trials to adjust their walking speed so as to pass through sliding doors that opened and closed at a frequency of 1 Hz. Concurrent feedback informed them about the possible need to accelerate or decelerate. Performance of participants who received concurrent feedback on 66% of the practice trials (on average) did not differ significantly from performance of participants who did not receive concurrent feedback. Furthermore, participants of both of these groups significantly outperformed participants who received concurrent feedback on all practice trials. These results are discussed in relation to the perceptual-motor mechanisms that underlie the control of the action. Also discussed are implications for future research, including the use of self-controlled feedback and the use of multisensory training programs.     

Direct Learning

The theory of direct perception holds that perception is specific to properties of ambient energy arrays. This article explores a similar approach to perceptual and perceptual-motor learning: Change due to learning is portrayed as specific to properties of ambient energy arrays. This type of learning is labeled direct learning. It is argued that a theory of direct learning explains a wide range of phenomena in ecologically relevant and informationally rich situations as well as in simpler experimental situations. Previous experimental results are reanalyzed and reinterpreted from the perspective of direct learning. To achieve this, the notion of information space is introduced. In information spaces, points represent ambient energy variables, paths represent change due to learning, and vector fields represent information that guides learning. These concepts also allow the theory of direct learning to be connected to and to take advantage of the theory of ordinary differential equations.