Preference for familiar humans by rats

Many “higher” animals are commonly assumed to distinguish between individual humans. This belief is based largely on anecdotal reports; in reality, there is little empirical evidence to support human recognition in nonhuman species. We report that laboratory rats consistently chose a familiar human over an unfamiliar human following fourteen and five 10-min exposures and even following a single 10-min exposure. Furthermore, this preference was retained in the absence of additional contact for at least 5 months. These results confirm that laboratory rats can tell individual humans apart, a prerequisite for associating them with hedonic events. Such human-based conditioning, described by Pavlov and by Gantt, Newton, Royer, and Stephens (1966), may have important implications for animal research in a variety of settings.     

Understanding the Determinants of Consumer Composting Behavior1

This study compared 3 models of waste management behavior: (a) a theory of reasoned action model, (b) an environmental belief-behavior model, and (c) an integrated waste management model which is based on the theory of planned behavior. The three models were compared using data from a sample of over 1,400 individual respondents who each completed a survey and a 2-week diary of their consumer composting activities. Overall, the results suggest that while the environmental beliefs-behavior model and the integrated waste management models both fit the data well, the integrated waste management model provided better predictive power and offers significant insight into the factors that influence composting behavior.     

Husserl's debate with Heidegger in the margins of Kant and the Problem of Metaphysics

Husserl received from Martin Heidegger a copy of his Kant and the Problem of Metaphysics in the summer of 1929 not long before Husserl had determined to reread Heidegger's writings in order to arrive at a definitive position on Heidegger's philosophy. With this in view, Husserl reread and made extensive marginal comments in Being and Time and Kant and the Problem of Metaphysics. This essay by the translator of the remarks in KPM offers some historical background and comment on the importance of the remarks in KPM and attempts to describe Husserl's counterposition to Heidegger on six issues that divided the two major twentieth century philosophers.     

Need probability affects retention: A direct demonstration

Recent memory theory has emphasized the concept ofneed probability—that is, the probability that a given piece of learned information will be tested at some point in the future. It has been proposed that, in real-world situations, need probability declines over time and that the memory-loss rate is calibrated to match the progressive reduction in need probability (J. R. Anderson & Schooler, 1991). The present experiments were designed to examine the influence of the slope of the need-probability curve on the slope of the retention curve. On each of several trials, subjects memorized a list of digits, then retained the digits in memory for 1, 2, 4, 8, or 16 sec. Some trials ended with a recall test; other trials ended with the message, “no test.” In Experiment 1, the likelihood of encountering a memory test (i.e., the need probability) was made to either increase or decrease as the retention interval increased; in Experiment 2, need probability either was flat (invariant across retention intervals) or decreased as the retention interval increased. The results indicated that the shape of the need-probability curve influenced the slope of the retention curve (Experiment 1) and that the effect became larger as the experimental session progressed (Experiment 2). The findings support the notion that memory adapts to need probabilities and that the rate of forgetting is influenced by the slope of the need-probability curve. In addition, all of the forgetting curves approximated a power function, suggesting that need probability influences the slope but not the form of forgetting.     

Hippocampal synaptic plasticity during instrumental learning

present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.     

The Role of Emotion in the Construction of Career in Parent—Adolescent Conversations

The role of emotion in the construction of career has not always been clear despite its importance in people's lives and in counseling. Recent conceptualizations suggest that emotion is a complex relational process that is socially constructed. This study illustrates the role of emotion in the construction of career from an action theory perspective. Two parent—adolescent conversations about career from a group of 14 conversations are analysed in detail to demonstrate the ways in which emotions serve to energise action and career and lend context and meaning to the process of constructing career in the family setting.     

Hippocampal synaptic plasticity during instrumental learning

present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.     

Themes in Therapist Development During the First Three Months of Clinical Experience

The results of a qualitative research study designed to better understand the developmental processes active in beginning therapists during the first three months of clinical contact is reported. Thirteen beginning therapists were asked to complete a monthly log describing experiences impacting their clinical work and themselves as therapists during their first three months of client contact. Data analysis revealed that the primary developmental theme active during this period of time is the development of therapist confidence. Two additional themes, the development of an internal gauge on which to evaluate current experiences and the development of boundaries around the self as a professional, were also found to be active during this time. These additional themes support the development of therapist confidence. Implications for training and research are identified.     

EXAMINING THE THEORY AND CLINICAL UTILITY OF WRITING ABOUT EMOTIONAL EXPERIENCES

Abstract— Pennebaker's (this issue) intervention for writing about emotional experiences shows promise as a module for inclusion in therapeutic packages. There are conceptual, methodological ant practical issues to be considered, however. These issues are discussed, and parallels are drawn from the literatures on the moodregulatory function of dreams and on the effects of social support on health. Although there is evidence that anything about emotional experiences has beneficial effects on health, it is premature to recommend writing intervention as a treatment component for specific problems. What is needed at this point is systematic research to evaluate to clinical utility.