Discriminated interresponse times: role of autoshaped responses.

When discriminated interresponse-time (IRT) procedures have been used to assess preference relations among temporally extended operants, deviations from matching have been obtained. Using a yoked-control procedure, the present study found that key pecking in a discriminated IRT procedure has two sources of strength--that arising from the response-reinforcer contingency that is explicitly arranged, and that arising from a stimulus-reinforcer contingency that is a by-product of the explicitly arranged contingency. The key pecking of all lead birds, and that of 3 of the 4 birds exposed to a yoked autoshaping procedure, was controlled by the keylight that signaled the lead birds' criterion IRTs. Because stimulus control of key pecking by the keylight, whether autoshaped or discriminative, fosters deviations from matching, the discriminated IRT procedure does not provide an appropriate basis for conclusions about preference relations among IRTs.     

Doctoral training in behavior analysis: Training generalized problem-solving skills

This essay provides guidelines for designing a doctoral program in behavior analysis. First, we propose a general accomplishment for all behavior analytic doctoral students: that they be able to solve problems concerning individual behavior within a range of environments. Second, in order to achieve this goal, we propose that students be trained in conceptual and experimental analysis of behavior, the application of behavioral principles and the administration of behavioral programs. This training should include class work, but it should emphasize the immersion of students in a variety of environments in which they are required to use behavior analytic strategies. Third, we provide an example of a hypothetical graduate program that involves the proposed training. Finally, an evaluation plan is suggested for determining whether a training program is in fact producing students who are generalized problem-solvers. At each step, we justify our point of view from a perspective that combines principles from behavior analysis and educational systems design.     

Substance P facilitation of memory: effects in an appetitively motivated learning task

Food deprived, heterogeneous strain (HS/IBG) mice were trained on two different discrimination tasks for food reinforcement. In one experiment animals were trained to make spatial discriminations in a T maze. Immediately after training they were given subcutaneous injections of either substance P (1 ng/g) or vehicle. Twenty-four hours later the animals were given reversal training in the same maze. The results showed that substance P-treated animals took significantly longer to acquire the reversal habit than did control mice. In a second experiment, animals were trained to make visual discriminations in a T maze. Immediately after reaching acquisition criterion animals were injected with either substance P (1 ng/g) or vehicle. Different groups of mice were retrained on the same task either 1, 2, 3, or 7 days after original learning. Savings scores were calculated and, at every interval, substance P-treated mice retained the task better than control animals. One interpretation of these data is that substance P-treated mice remembered the original task significantly better than vehicle-injected control animals.     

Comprehension and expression of affect in language-impaired children

Eight children with developmental language impairment (LI) and eight age-, sex-, socioeconomic-status-, and I.Q.-matched controls were given tests of comprehension and expression of affective intent in spoken language and through facial expression. The LI children performed significantly more poorly than did controls in both comprehension and spontaneous expression of vocal affect. On tasks involving emotional facial expression, the opposite results were observed: The LI children were more dramatic in their expression of facial affect than were the controls. Children with language impairment appear to have a deficit in affective comprehension and expression that is modality-specific, i.e., limited to vocal affect. The heightened range of affective facial expression that they demonstrate may be a compensatory mechanism to offset their difficulties with vocal affect.This work was supported by grant 12-203 from the March of Dimes Birth Defects Foundation, and by NINDS grant NS22343 for the Center for the Study of the Neurological Basis of Language.     

A two year audit of a family therapy clinic in adult psychiatry

This paper reports a 2 year audit of a family therapy clinic in a psychiatric department, focusing especially on the relationship between diagnosis and outcome. Patients with affective disorders–especially where anxiety predominated–and eating disorders had good outcome. Structural change occurred in families with psychotic members, even though psychotic symptoms were often unchanged. Difficulties with an acute onset were more responsive than long-term problems, but a substantial number of the latter did improve. Families receiving between four and 10 sessions had the best outcome, and improvement was generally maintained at 2 year follow-up.     

Specificity of Dating Aggression and Its Justification Among High-Risk Adolescents

Ninety-five high-risk adolescents were studied to determine whether their dating aggression and its justification as a response to interpersonal problems were specific to the current partner, general to dating relationships, or part of a global age-mate (same-sex peers and opposite-sex dating partners) aggression problem. Approximately one-third of males and two-thirds of females reported physical aggression against their current dating partner. Males' aggression (and its justification) toward their current dating partner was part of a generalized pattern of dating aggression, whereas for females, physical aggression against a current dating partner (and its justification) was partner-specific and unrelated to aggression in other relationships. Findings are discussed with regard to intervention and future research on adolescent dating aggression.     

Quantification of three-dimensional structures

A mathematical model, based on additive subcomponents of grouping, subitizing and adding, was derived to account for quantification latencies of three-dimensional block arrangements. Subitizing is the process that people use to directly quantify a small number of objects without counting. It was found that most people consistently subitized up to four blocks. With more than four blocks, people resorted to grouping and adding, and the model was able to account for these data. The structural variables of compactness, symmetry, linearity, and planarity were shown to have small effects on quantification latencies relative to the large effect of number of blocks. Of these structural variables, compactness had the largest effect, and in terms of the model, it is suggested that visual structure had its effect on the perceptual grouping subcomponent.     

Clients' perspectives on problems many years after traumatic brain injury

This study investigated the types of self-reported main problems that persons report many years following a traumatic brain injury. This preliminary study is part of a large ongoing study of disability and handicap in adults following traumatic brain injury. As part of an extensive interview, subjects were asked an open-ended question regarding their current main problems which they thought resulted from their traumatic brain injury. Responses were obtained from 166 adult subjects (119 men and 47 women) whose time postinjury ranged from 9 to 24 years. Categories for responses were subsequently developed. The most commonly reported categories of problems were those relating to movement (39%), cognition (36%), and sensory impairment (31%). Findings suggest that subjects' long-term concerns were related to specific impairments more than to psychosocial, emotional, or behavioral issues. Methodological issues concerning this research are discussed in relation to findings.     

Effects of rate building on fluent performance: a review and commentary

The use of rate-building procedures to encourage the production of high response rates and to develop fluency has been increasingly justified by research on precision teaching and automaticity. Rate-building procedures often ensure both speed and accuracy, and claims have been made that such procedures result in greater retention, persistence, and generalization of trained skills, as well as preference by students. Given the potential importance of these claims for behavior analysts and educators alike, this review assesses the validity, generality, and implications of research on rate building. The review revealed sparse empirical evidence that retention, persistence, and generalization of skills result from the use of rate-building procedures when the effects of practice and reinforcement rate are controlled. Given the results of this review, the implications are discussed in the context of behavior-analytic research (e.g., behavioral momentum), and further research is recommended.