Discrimination and generalization by rats of temporal stimuli lasting for minutes

In three experiments, rats learned to respond differentially to reinforced and nonreinforced trials when the length of the intertrial interval (ITI) predicted the trial outcome (reinforcement or nonreinforcement). Rats in control groups, for whom the length of the ITI did not predict the outcome, did not show differential performance on nonreinforced and reinforced trials. Generalization gradients obtained following discrimination training were comparable to those obtained following discrimination training with other types of discriminative stimuli. That is, groups which had shown differential performance in discrimination training yielded generalization gradients with fastest speeds at the previously reinforced ITIs, slowest speeds at the previously nonreinforced ITIs, and intermediate speeds at ITIs of intermediate length. Control groups yielded flat gradients across all ITIs tested. These effects were shown for relative time discrimination (short time = reinforcement, long time = nonreinforcement, or the reverse) and also for an absolute time discrimination (long and short time = reinforcement, middle time = nonreinforcement or the reverse). This method was effective for time duration measured in minutes rather than seconds, as is more commonly the case.     

Dynamic processes in music perception

A schema-based theory of music perception that describes the dynamic interaction between the musical event and the listener’s knowledge of the underlying regularities in tonal music is proposed. Three properties of musical schema are evaluated in a recognition memory experiment: (1) The schema engages a subset of the abstract knowledge system that is determined by the predominant key of the musical sequence, (2) the schema evaluates both interval relations and the functions of the sounded elements within the established tonal framework, and (3) the schema interacts continuously with the musical event in time to process pitch information in its temporal context. Listeners are required to identify the serial position of a chord that is changed between two successive chord sequences that are otherwise identical. The experiment measures the magnitude and the temporal extent of the disruptive effect of including in the sequence an element outside the tonal framework. The results show temporally specific effects on memory for pitch relations consistent with the operation of a musical schema. Comparisons are made with schema-based theories applied in other perceptual and cognitive domains.     

Working through a group's fantasy of the deceased leader's wish for the group's continuation

This paper reflects the working through of a group's fantasy that the deceased group leader wished the group to continue. As in any defense, the fantasy protected members from the pain of the finality of the leader's death. This article reveals the subjective experience concerning the effect of the leader's death on the group and members' intrapsychic struggle to separate and individuate from the deceased leader, while attending to and striving toward the group's continuation. The group's painful and growing individuation enabled the group to follow its own tasks without the spector of the deceased leader.     

The Effects of Procedures, Social Accounts, and Benefits Level on Victims' Layoff Reactions

Three hundred and fifty-three layoff victims responded to questions describing their reactions to layoffs. Victims also described management layoff practices. Two measures of procedural fairness in layoff practices (decision-making characteristics and social accounts) and one measure of layoff outcomes (benefits level) were included. Only decision-making characteristics predicted exemployee willingness to recruit for a former employer and desire for regulation of layoffs. These results provide further evidence of the importance of procedural justice in organizational decision-making.     

Social influences on remembering: Intellectual,interpersonal and intergroup components

When people recall an event collaboratively we may expect the product to be influenced by the combined cognitive resources of the group, interpersonal acquaintance of the members, and social competition engendered by salient intergroup considerations. Using undergraduate students and serving police officers as subjects, a range of experimental conditions was established which varied on the three factors of cognitive resources of the participants (Cognitive Resources), interpersonal acquaintance of the participants (Interpersonal Acquaintance) and professional salience (Professional Salience) of the recall material. Participants answered a questionnaire concerning a police interrogation they had witnessed, and rated how much confidence they had in their answers. Multiple regression revealed statistically significant associations between (i) Cognitive Resources and number of correct answers, (ii) Interpersonal Acquaintance and confidence for implicational errors, and (iii) Professional Salience and (a) number of implicational errors and (b) confidence in confusional errors. The theoretical implications for our understanding of memory as a social process are discussed, and the practical implications for courtroom testimony briefly described.     

Somatic complaints in anxious children

Although stomachaches and headaches are considered characteristic of children with anxiety disorders, there is converging evidence that a broader range of somatic symptoms may be associated with children's expressions of anxiety. The purpose of this study was to determine the prevalence of somatic complaints in anxious children. The results indicated that children with anxiety disorders endorsed the presence of many different somatic complaints, and that contrary to clinical intuition, stomaches and headaches were not among the most commonly reported symptoms. In addition, the anxious children endorsed significantly more somatic complaints when compared to normal controls. Furthermore, the symptom pattern reported by anxious children indicated the presence of both the somatic and cognitive components usually associated with panic attacks, although none of the children met diagnostic criteria for panic disorder. The results are discussed in terms of the contribution of somatic symptoms to the understanding of anxiety disorders in children.     

The specificity of the effects of stimulant medication on classroom learning-related measures of cognitive processing for Attention Deficit Disorder children

There appear to be beneficial effects of stimulant medication on daily classroom measures of cognitive functioning for Attention Deficit Disorder (ADD) children, but the specificity and origin of such effects is unclear. Consistent with previous results, 0.3 mg/kg methylphenidate improved ADD children's performance on a classroom reading comprehension measure. Using the Posner letting-matching task and four additional measures of phonological processing, we attempted to isolate the effects of methylphenidate to parameter estimates of (a) selective attention, (b) the basic cognitive process of retrieving name codes from permanent memory, and (c) a constant term that represented nonspecific aspects of information processing. Responses to the letter-matching stimuli were faster and more accurate with medication compared to placebo. The improvement in performance was isolated to the parameter estimate that reflected nonspecific aspects of information processing. A lack of medication effect on the other measures of phonological processing supported the Posner task findings in indicating that methylphenidate appears to exert beneficial effects on academic processing through general rather than specific aspects of information processing.