Local and Global Sources of Control in Pigeon Delayed Matching-to-sample Performance

The present study employed a behavioural detection approach to investigate the combined effects of sample duration and sample presentation frequency on delayed matching accuracy of pigeons. Experiment 1 showed that when both samples were exposed at each of the two possible durations within a two-alternative, delayed matching session, discriminability was higher to the longer duration sample than to the short-duration sample, as found when sample duration is varied between sessions. Experiment 2's asymmetrical procedure increased bias toward the more frequent of the two samples but had no influence on discriminability. Initial discriminability was higher to samples exposed for longer durations, irrespective of stimulus presentation frequency. The results suggest qualitatively different effects of the two sources of stimulus control under consideration: Sample duration (a local or within-trial manipulation) exerted its effect on discrimination of the stimuli, whereas sample presentation frequence (a global factor) exerted its major effect on response bias. An interpretation of the data in terms of Blough's (1996) analysis of errors in matching tasks suggests that the amount of behaviour under control of the sample stimulus markedly changed with different sample durations. The analysis also showed that the biasing manipulation exerted most of its effect on the portion of behaviour outside of control by the critical stimulus. We argue that theoretical accounts of delayed matching performance need to consider both local and global factors as determinants of matching accuracy.     

Elemental and Configural Processes in Patterning Discrimination Learning

Three experiments used appetitive conditioning with rats to examine the involvement of elemental and configural processes in positive and negative patterning discriminations. The first experiment demonstrated that negative and, to some extent, positive patterning discriminations were learned more rapidly when these discriminations consisted of stimulus elements that had previously been the reinforced as opposed to the non-reinforced elements of a simple discrimination. Experiment 2 revealed an excitatory summation effect during the early phase of negative patterning learning that depended upon discrimination pretraining. The final experiment demonstrated faster discrimination learning between the compound and the less salient, rather than the more salient, element of an instrumental patterning task. The present set of results were interpreted as reflecting the possibility, consistent with connectionist theory, that internal representations of the conditioned stimuli change over the course of a patterning discrimination.     

An Exploration of Family Problem-Solving and Affective Involvement as Moderators Between Disease Severity and Depressive Symptoms in Adolescents with Inflammatory Bowel Disease

Little is known about how family functioning relates to psychosocial functioning of youth with inflammatory bowel disease (IBD). The study aim was to examine family problem solving and affective involvement as moderators between adolescent disease severity and depressive symptoms. Participants were 122 adolescents with IBD and their parents. Measures included self-reported and parent-reported adolescent depressive symptoms, parent-reported family functioning, and physician-completed measures of disease severity. Disease severity was a significant predictor of adolescent-reported depressive symptoms, but not parent-reported adolescent depressive symptoms. Family affective involvement significantly predicted parent-reported adolescent depressive symptoms, while family problem-solving significantly predicted adolescent self-report of depressive symptoms. Neither affective involvement nor problem-solving served as moderators. Family affective involvement may play an important role in adolescent emotional functioning but may not moderate the effect of disease severity on depressive symptoms. Research should continue to examine effects of family functioning on youth emotional functioning and include a sample with a wider range of disease severity to determine if interventions aimed to enhance family functioning are warranted.     

An examination of learning processes during critical incident training: implications for the development of adaptable trainees

Three experiments are reported that examined the process by which trainees learn decision-making skills during a critical incident training program. Formal theories of category learning were used to identify two processes that may be responsible for the acquisition of decision-making skills: rule learning and exemplar learning. Experiments 1 and 2 used the process dissociation procedure (L. L. Jacoby, 1998) to evaluate the contribution of these processes to performance. The results suggest that trainees used a mixture of rule and exemplar learning. Furthermore, these learning processes were influenced by different aspects of training structure and design. The goal of Experiment 3 was to develop training techniques that enable trainees to use a rule adaptively. Trainees were tested on cases that represented exceptions to the rule. Unexpectedly, the results suggest that providing general instruction regarding the kinds of conditions in which a decision rule does not apply caused them to fixate on the specific conditions mentioned and impaired their ability to identify other conditions in which the rule might not apply. The theoretical, methodological, and practical implications of the results are discussed.     

Trait and social processes in the link between social support and affect: an experimental, laboratory investigation

This study investigated the extent to which the link between perceived social support and affect reflected support recipients' trait perceived support as well as three distinct social processes: the objective supportiveness of providers, the unique relationships among recipients and providers that were stable over occasions, as well as the unique relationships that varied across occasions. Ten recipients interacted with each of the same four providers on five separate occasions, for a total of 200 interactions. Recipients and independent observers rated recipient affect and provider support. Greater perceived support was related to greater positive affect for recipients' trait perceived support, as well as for relationships that were stable over occasions and relationships that varied across occasions. No social support effects were found for negative affect. Perceived similarity was a consistent predictor of recipients' support perceptions. Implications for social support models and interventions were discussed.     

The relationship between pre-treatment clinical profile and treatment outcome in an integrated stuttering program

A procedure for subtyping individuals who stutter and its relationship to treatment outcome is explored. Twenty-five adult participants of the Comprehensive Stuttering Program (CSP) were classified according to: (1) stuttering severity and (2) severity of negative emotions and cognitions associated with their speech problem. Speech characteristics (percentage of stuttered syllables, distorted speech score, and the number of correctly produced syllables on a diadochokinesis task) and emotional/cognitive states (emotional reaction, speech satisfaction, and attitudes toward speaking) were assessed before and after treatment, and at a 1- and 2-year follow-up. The results showed that: (a) there was no relationship between stuttering severity and the severity of negative emotions and cognitions, (b) the severe stuttering group had the largest treatment gains but also the highest level of regression, and (c) at post-treatment and both follow-up assessments the differences on measures of emotions between the mild and severe emotional group had disappeared, chiefly due to a large decrease in the latter group's negative emotions and cognitions. Our findings show that, based on treatment gains, specific subgroups can be identified, each requiring different treatment approaches. This underlines the necessity of developing a better understanding of how various dimensions of stuttering relate to treatment outcome. Educational objectives: The reader will be able to: (1) describe why stuttering severity and negative emotions and cognitions that are related to stuttering should be investigated separately and (2) describe how treatment outcome relates to subtypes of persons who stutter.     

FUNCTIONAL ANALYSIS AND TREATMENT OF ELOPEMENT ACROSS TWO SCHOOL SETTINGS

The elopement of a child with Asperger syndrome was assessed using functional analyses and was treated in two school settings (classroom and resource room). Functional analyses indicated that elopement was maintained by access to attention in the resource room and obtaining a preferred activity in the classroom. Attention- and tangible-based interventions were compared in an alternating treatments design in both settings. Results validated the findings of the functional analyses. Implications for the assessment and treatment of elopement are discussed.