EFFECTS OF D‐AMPHETAMINE IN A TEMPORAL DISCRIMINATION PROCEDURE: SELECTIVE CHANGES IN TIMING OR RATE DEPENDENCY?

Two experiments evaluated rate dependency and a neuropharmacological model of timing as explanations of the effects of amphetamine on behavior under discriminative control by time. Four pigeons pecked keys during 60-trial sessions. On each trial, the houselight was lit for a particular duration (5 to 30 s), and then the key was lit for 30 s. In Experiment 1, the key could be lit either green or blue. If the key was lit green and the sample was 30 s, or if the key was lit blue and the sample was 5 s, pecks produced food on a variable-interval 20-s schedule. The rate of key pecking increased as a function of sample duration when the key was green and decreased as a function of sample duration when the key was blue. Acute d-amphetamine (0.1 to 3.0 mg/kg) decreased higher rates of key pecking and increased lower rates of key pecking as predicted by rate dependency, but did not shift the timing functions leftward (toward overestimation) as predicted by the neuropharmacological model. These results were replicated in Experiment 2, in which the key was lit only one color during sessions, indicating that the effects were not likely due to disruption of discriminative control by key color. These results are thus consistent with rate dependency but not with the predictions of the neuropharmacological model.     

Peer-mediated reinforcement plus prompting as treatment for off-task behavior in children with attention deficit hyperactivity disorder

Functional analyses revealed that peer attention was one variable maintaining the off-task behavior exhibited by 3 students with a diagnosis of attention deficit hyperactivity disorder (ADHD). Peer-mediated reinforcement plus prompting was then used to reduce off-task behavior in a simulated classroom environment. Implications for future applications of this procedure with children diagnosed with ADHD are discussed.     

Aging and monitoring associative learning: is monitoring accuracy spared or impaired?

Mixed lists of associatively related and unrelated paired associates were used to study monitoring of associative learning. Older and younger adults produced above-chance levels of relative accuracy, as measured by intraindividual correlations (gamma) of judgments of learning (JOLs) with item recall. JOLs were strongly influenced by relatedness, and this effect was greater for older adults. Relative accuracy was higher for unrelated than for related pairs. Correlations of JOLs with item recall for a randomly yoked learner indicated that access to one's own encoding experiences increased relative accuracy. Both age groups manifested a contrast effect (lower JOLs for unrelated items when mixed with related items). Aging appears to spare monitoring of encoding, even though it adversely affects associative learning.     

A justification-suppression model of the expression and experience of prejudice

The authors propose a justification-suppression model (JSM), which characterizes the processes that lead to prejudice expression and the experience of one's own prejudice. They suggest that "genuine" prejudices are not directly expressed but are restrained by beliefs, values, and norms that suppress them. Prejudices are expressed when justifications (e.g., attributions, ideologies, stereotypes) release suppressed prejudices. The same process accounts for which prejudices are accepted into the self-concept The JSM is used to organize the prejudice literature, and many empirical findings are recharacterized as factors affecting suppression or justification, rather than directly affecting genuine prejudice. The authors discuss the implications of the JSM for several topics, including prejudice measurement, ambivalence, and the distinction between prejudice and its expression.     

Accuracy of discrimination,rate of responding,and resistance to change

Pigeons were trained on multiple schedules in which responding on a center key produced matching-to-sample trials according to the same variable-interval 30-s schedules in both components. Matching trials consisted of a vertical or tilted line sample on the center key followed by vertical and tilted comparisons on the side keys. Correct responses to comparison stimuli were reinforced with probability .80 in the rich component and .20 in the lean component. Baseline response rates and matching accuracies generally were higher in the rich component, consistent with previous research. When performance was disrupted by prefeeding, response-independent food during intercomponent intervals, intrusion of a delay between sample and comparison stimuli, or extinction, both response rates and matching accuracies generally decreased. Proportions of baseline response rate were greater in the rich component for all disrupters except delay, which had relatively small and inconsistent effects on response rate. By contrast, delay had large and consistent effects on matching accuracy, and proportions of baseline matching accuracy were greater in the rich component for all four disrupters. The dissociation of response rate and accuracy with delay reflects the localized impact of delay on matching performance. The similarity of the data for response rate and accuracy with prefeeding, response-independent food, and extinction shows that matching performance, like response rate, is more resistant to change in a rich than in a lean component. This result extends resistance to change analyses from the frequency of response emission to the degree of stimulus control, and suggests that the strength of discriminating, like the strength of responding, is positively related to rate of reinforcement.     

The structure of the cognitive revolution: an examination from the philosophy of science

The received view is that psychology has undergone several scientific revolutions similar to those that occurred in the physical sciences. Of these, this paper will consider the cognitive revolution. Because the arguments in favor of the existence of a cognitive revolution are cast using the concepts and terms of revolutionary science, we will examine the cognitive revolution using accounts of revolutionary science advanced by five influential philosophers of science. Specifically, we will draw from the philosophical positions of Popper, Kuhn, Lakatos, Laudan, and Gross for the purpose of discussion. We conclude that no substantive revolution took place according to these accounts. This conclusion is based on data gathered from some of the major participants in the "cognitive revolution" and on a general scholarly survey of the literature. We argue that the so-called cognitive revolution is best characterized as a socio-rhetorical phenomenon.     

Solution-focused family therapy with three aggressive and oppositional-acting children: an N = 1 empirical study

The efficacy of Solution-Focused Family Therapy (SFFT) for helping three families with aggressive and oppositional-acting children (aged 8-9) was examined. The N = 1 multiple-baseline design with three replications used validated measures, a treatment manual, and a treatment integrity measure. The interventions lasted from four to five sessions. SFFT appeared to be effective with the families at post-treatment and 3-month follow up.