The Isolation, Primacy, and Recency Effects Predicted by an Adaptive LTD/LTP Threshold in Postsynaptic Cells

An item that stands out (is isolated) from its context is better remembered than an item consistent with the context. This isolation effect cannot be accounted for by increased attention, because it occurs when the isolated item is presented as the first item, or by impoverished memory of nonisolated items, because the isolated item is better remembered than a control list consisting of equally different items. The isolation effect is seldom experimentally or theoretically related to the primacy or the recency effects—that is, the improved performance on the first few and last items, respectively, on the serial position curve. The primacy effect cannot easily be accounted for by rehearsal in short-term memory because it occurs when rehearsal is eliminated. This article suggests that the primacy, the recency, and the isolation effects can be accounted for by experience-dependent synaptic plasticity in neural cells. Neurological empirical data suggest that the threshold that determines whether cells will show long-term potentiation (LTP) or long-term depression (LTD) varies as a function of recent postsynaptic activity and that synaptic plasticity is bounded. By implementing an adaptive LTP-LTD threshold in an artificial neural network, the various aspects of the isolation, the primacy, and the recency effects are accounted for, whereas none of these phenomena are accounted for if the threshold is constant. This theory suggests a possible link between the cognitive and the neurological levels.     

Technical intelligence in animals: the kea model

The ability to act on information flexibly is one of the cornerstones of intelligent behavior. As particularly informative example, tool-oriented behavior has been investigated to determine to which extent nonhuman animals understand means-end relations, object affordances, and have specific motor skills. Even planning with foresight, goal-directed problem solving and immediate causal inference have been a focus of research. However, these cognitive abilities may not be restricted to tool-using animals but may be found also in animals that show high levels of curiosity, object exploration and manipulation, and extractive foraging behavior. The kea, a New Zealand parrot, is a particularly good example. We here review findings from laboratory experiments and field observations of keas revealing surprising cognitive capacities in the physical domain. In an experiment with captive keas, the success rate of individuals that were allowed to observe a trained conspecific was significantly higher than that of naive control subjects due to their acquisition of some functional understanding of the task through observation. In a further experiment using the string-pulling task, a well-probed test for means-end comprehension, we found the keas finding an immediate solution that could not be improved upon in nine further trials. We interpreted their performance as insightful in the sense of being sensitive of the relevant functional properties of the task and thereby producing a new adaptive response without trial-and-error learning. Together, these findings contribute to the ongoing debate on the distribution of higher cognitive skills in the animal kingdom by showing high levels of sensorimotor intelligence in animals that do not use tools. In conclusion, we suggest that the 'Technical intelligence hypothesis' (Byrne, Machiavellian intelligence II: extensions and evaluations, pp 289-211, 1997), which has been proposed to explain the origin of the ape/monkey grade-shift in intelligence by a selection pressure upon an increased efficiency in foraging behavior, should be extended, that is, applied to some birds as well.     

Social cognitive theory of posttraumatic recovery: the role of perceived self-efficacy

The present article integrates findings from diverse studies on the generalized role of perceived coping self-efficacy in recovery from different types of traumatic experiences. They include natural disasters, technological catastrophes, terrorist attacks, military combat, and sexual and criminal assaults. The various studies apply multiple controls for diverse sets of potential contributors to posttraumatic recovery. In these different multivariate analyses, perceived coping self-efficacy emerges as a focal mediator of posttraumatic recovery. Verification of its independent contribution to posttraumatic recovery across a wide range of traumas lends support to the centrality of the enabling and protective function of belief in one's capability to exercise some measure of control over traumatic adversity.     

Developing new treatments: on the interplay between theories, experimental science and clinical innovation

It is often argued that behaviour therapy and cognitive-behaviour therapy have a sound theoretical and experimental basis. In the early days of behaviour therapy, the learning theory accounts that were the basis of treatment made clear suggestions about the procedures that were likely to be effective in treatment. In contrast, more recent cognitive-behavioural models tend to specify targets for therapy, but not the procedures that might be optimal for changing the targets. As a consequence, a considerable amount of work has to be done in order to create an effective cognitive-behavioural treatment from a promising cognitive-behavioural model. The process by which cognitive-behavioural treatments are developed is rarely discussed in the literature. For this reason, the way in which one group has used a mixture of phenomenological, experimental and treatment development studies to create effective cognitive therapy programmes for anxiety disorders is described.     

The influence of provocateurs' emotion displays on the social information processing of children varying in social adjustment and age

This study examined the effect of provocateurs' emotion displays on first through fourth graders' social information processing (SIP). Rating and nomination sociometric techniques were used to identify rejected-aggressive, rejected-nonaggressive, average-nonaggressive, and popular-nonaggressive groups. Children viewed videotaped ambiguous provocation situations in which provocateurs' emotion displays were varied systematically. After each vignette, children's recall of story details, attribution of intent, and problem-solving responses were obtained. Half of the children were randomly assigned to a condition where they were asked directly about provocateurs' emotions, and the remaining children were not asked about provocateurs' feelings. Results revealed both developmental and social adjustment differences in SIP. In addition, provocateurs' emotion displays and asking versus not asking about those displays influenced multiple aspects of SIP.     

Suggestibility, social support, and memory for a novel experience in young children

This study examined 5- and 6-year-olds' suggestibility and interviewer demeanor as joint predictors of their memory for a novel experience. Session 1 consisted of children taking part in a novel laboratory event. Session 2 took place after approximately a 1-week delay and consisted of children completing both a memory test concerning what happened during the prior event and the Video Suggestibility Scale for Children (VSSC). During the second session, the interviewer behaved either supportively or nonsupportively. Greater acquiescence on the VSSC was associated with fewer correct responses to misleading questions about the laboratory event in the supportive and nonsupportive conditions and with more errors in response to specific questions in the nonsupportive condition. Results indicate that individual differences in children's suggestibility are related to the accuracy of their memory for separate events, although some of these relations may vary depending on the context in which children are interviewed.     

Gradations of emulation learning in infants' imitation of actions on objects

This study explored different gradations of emulation in the imitation of actions on objects by 17-month-olds. Experiment 1 established levels of behavioral reproduction following prerecorded video demonstrations similar to those levels following live demonstrations. In Experiment 2, two digitally modified videos, where object movements or body movements critical to producing the target action were highlighted in isolation, were developed. Infants produced the target action equally frequently by observing the object movement video and observing the unmodified video. In contrast, their performance was much less successful based on the body movement video. In Experiment 3, the performance obtained following the object movement video was similar to that following a further video that emphasized the object movements produced in unsuccessful attempts to produce the target action. These findings suggest that emulation in the form of object movement reenactment or affordance learning plays a role in the social learning of actions on objects during infancy.     

The applicability of deadline models: Comment on Glickman,Gray, and Morales (2005)

Glickman, Gray, and Morales (this issue) propose a statistical model for measuring the unobserved latency of stimulus-controlled processes. The model accounts for both speed and accuracy and does so by assuming participants set an internal deadline. If a stimulus-controlled response is not produced by the deadline, the participant then guesses. The applicability the model is discussed in this comment. The deadline model yields specific predictions for the case in which stimulus difficulty is manipulated in a within-block manner. In this case, it is reasonable to assume that stimulus difficulty does not affect the deadline. It is shown that in common perceptual and cognitive domains, extant data do not fully meet these predictions. Hence, practitioners need be aware of the possibility and consequences of model misspecification. This research is supported by NSF grant SES - 0095919 to J. Rouder, D. Sun, and P. Speckman.     

History and Method of Charles V. Gerkin’s Pastoral Theology: Toward an Identity-Embodied and Community-Embedded Pastoral Theology,Part II. Method

The purpose of this article is to explore the legacy of Charles V. Gerkin’s pastoral theology and to construct a method of pastoral theology. In Part I, I will trace within a larger context of pastoral theology the history of Gerkin’s pastoral theology since his early clinical praxis. In Part II, I will explore his method of developing pastoral theology and construct a renewed critical and constructive method of pastoral theology, reflecting on the implications of exploring the history and method of his pastoral theology.     

Racial-Ethnic Differences in Genetic Amniocentesis Uptake

The objective of this study was to determine the role of health beliefs in genetic amniocentesis acceptance in a diverse racial-ethnic population. Participants completed a previously-validated questionnaire consisting of three sections: (1) demographics, (2) amniocentesis knowledge, and (3) health beliefs, which assessed perceived susceptibility, seriousness of potential impact, benefits of testing, and barriers to testing. The results showed that Hispanic women were less likely to accept amniocentesis (51.5% vs. Caucasian 82.8%, African American 82.9%, Asian 82.8%). Education level was the only demographic factor higher among acceptors. Women who accepted amniocentesis had higher perceived seriousness, susceptibility, and benefits HBM scores and higher knowledge scores than women who declined. HBM scores and knowledge predicted the amniocentesis decision correctly 91.5% of the time. Individual health beliefs and knowledge play a greater role in genetic amniocentesis acceptance than do demographic factors such as race-ethnicity.