Conditional discrimination in mentally retarded subjects: programming acquisition and learning set.

In Experiment 1, 3 subjects with retardation were exposed to two visual-visual arbitrary matching-to-sample problems each day. One conditional discrimination was presented under trial-and-error conditions, and the other was presented under a component training procedure. The latter began by establishing the comparison discrimination and its rapid reversal. The successive discrimination between the sample stimuli was established through differential naming. Then, sample naming was maintained in conditional discrimination sessions in which the same sample was presented in blocks of consecutive trials. Block size was decreased across sessions until sample presentation was randomized as in trial-and-error training (but with naming maintained). Two subjects initially learned only with component training. The performance of the 3rd subject was inconsistent across conditional discriminations. One of the successful subjects ultimately learned rapidly and consistently with trial-and-error procedures. Experiment 2 sought to demonstrate learning set in the other 2 subjects. Elements of the component training procedure were withdrawn over successive conditional discriminations. Ultimately, 1 subject nearly always learned under trial-and-error conditions, and the other learned under trial-and-error conditions combined with differential sample naming.     

Verbal self-reports of delayed matching to sample by humans

Undergraduates participated in two experiments to develop methods for the experimental analysis of self-reports about behavior. The target behavior was the choice response in a delayed-matching-to-sample task in which monetary reinforcement was contingent upon both speed and accuracy of the choice. In Experiment 1, the temporal portion of the contingency was manipulated within each session, and the presence and absence of feedback about reinforcement was manipulated across sessions. As the time limits became stricter, target response speeds increased, but accuracy and reinforcement rates decreased. When feedback was withheld, further reductions in speed and reinforcement occurred, but only at the strictest time limit. Thus, the procedures were successful in producing systematic variation in the speed, accuracy, and reinforcement of the target behavior. Experiment 2 was designed to assess the influence of these characteristics on self-reports. In self-report conditions, each target response was followed by a computer-generated query: “Did you earn points?” The subject reported by pressing “Yes” or “No” buttons, with the sole consequence of advancing the session. In some cases, feedback about reinforcement of the target response followed the reports; in other cases it was withheld. Self-reports were less accurate when the target responses occurred under greater time pressure. When feedback was withheld, the speed of the target response influenced reports, in that the probability of a “Yes” report increased directly with the speed of accurate target responses. In addition, imposing the self-report procedure disrupted target performance by reducing response speeds at the strictest time limit. These results allow investigation of issues in both behavioral and cognitive psychology. More important, the overall order in the data suggests promise for the experimental analysis of self-reports by human subjects.     

A weighted procrustes criterion

The Procrustes criterion is a common measure for the distance between two matricesX andY, and can be interpreted as the sum of squares of the Euclidean distances between their respective column vectors. Often a weighted Procrustes criterion, using, for example, a weighted sum of the squared distances between the column vectors, is called for. This paper describes and analyzes the performance of an algorithm for rotating a matrixX such that the column-weighted Procrustes distance toY is minimized. The problem of rotatingX intoY such that an aggregate measure of Tucker's coefficient of congruence is maximized is also discussed.We wish to thank Richard A. Harshman and C. F. Jeff Wu for valuable discussions in the early stages of this work. We would also like to thank Jos ten Berge, John Gower, and the Editor, Associate Editor, and referees whose comments and suggestions greatly improved this paper.     

Basic and applied research on extinction bursts

Discontinuation of the contingency between a response and its reinforcer sometimes produces a temporary increase in the response before its rate decreases, a phenomenon called the extinction burst. Prior clinical and basic studies on the prevalence of the extinction burst provide highly disparate estimates. Existing theories on the extinction burst fail to account for the dynamic nature of this phenomenon, and the basic behavioral processes that control response bursting remain poorly understood. In this paper, we first review the basic and applied literature on the extinction burst. We then describe a recent refinement of the concatenated matching law called the temporally weighted matching law that appears to resolve the above-mentioned issues regarding the extinction burst. We present illustrative translational data based conceptually on the model. Finally, we discuss specific recommendations derived from the temporally weighted matching law regarding procedures clinicians could implement to potentially mitigate or prevent extinction bursts.     

The Integration of Family and Group Therapy as an Alternative to Juvenile Incarceration: A Quasi‐Experimental Evaluation Using Parenting with Love and Limits

The current study employed a quasi‐experimental design using both intent‐to‐treat and protocol adherence analysis of 155 moderate‐ to high‐risk juvenile offenders to evaluate the effectiveness of Parenting with Love and Limits® (PLL), an integrative group and family therapy approach. Youth completing PLL had significantly lower rates of recidivism than the comparison group. Parents also reported statistically significant improvements in youth behavior. Lengths of service were also significantly shorter for the treatment sample than the matched comparison group by an average of 4 months. This study contributes to the literature by suggesting that intensive community‐based combined family and group treatment is effective in curbing recidivism among high‐risk juveniles.     

Teaching identity matching of braille characters to beginning braille readers

We taught three children with visual impairments to make tactile discriminations of the braille alphabet within a matching‐to‐sample format. That is, we presented participants with a braille character as a sample stimulus, and they selected the matching stimulus from a three‐comparison array. In order to minimize participant errors, we initially arranged braille characters into training sets in which there was a maximum difference in the number of dots comprising the target and nontarget comparison stimuli. As participants mastered these discriminations, we increased the similarity between target and nontarget comparisons (i.e., an approximation of stimulus fading). All three participants’ accuracy systematically increased following the introduction of this identity‐matching procedure.     

Can pictures promote the acquisition of sight‐word reading? An evaluation of two potential instructional strategies

Sight‐word instruction can be a useful supplement to phonics‐based methods under some circumstances. Nonetheless, few studies have evaluated the conditions under which pictures may be used successfully to teach sight‐word reading. In this study, we extended prior research by examining two potential strategies for reducing the effects of overshadowing when using picture prompts. Five children with developmental disabilities and two typically developing children participated. In the first experiment, the therapist embedded sight words within pictures but gradually faded in the pictures as needed using a least‐to‐most prompting hierarchy. In the second experiment, the therapist embedded text‐to‐picture matching within the sight‐word reading sessions. Results suggested that these strategies reduced the interference typically observed with picture prompts and enhanced performance during teaching sessions for the majority of participants. Text‐to‐picture matching also accelerated mastery of the sight words relative to a condition under which the therapist presented text without pictures.     

Allocation of speech in conversation

In a replication and extension of Conger and Killeen's (1974) widely cited demonstration of matching in conversations, we evaluated nine participants’ allocation of speech and gaze to two conversational partners. German speakers participated in two 90‐min sessions in which confederates uttered approval on independent variable‐interval schedules. In one of the sessions, confederates uttered approval contingent upon and contiguous with eye contact whereas in the other session approval was uttered independent of the participant's gaze. Several measures of participants’ verbal behavior were taken, including relative duration and rate of speech and gaze. These were compared to confederates’ relative rate of approval and relative duration and rate of talk. The generalized matching equation was fitted to the various relations between participants’ behavior and confederates’ behavior. Conger and Killeen's results were not replicated; participants’ response allocation did not show a systematic relation to the confederates’ relative rate of approval. The strongest relations were to overall talk, rather than approval. In both conditions, the participant talked more to the confederate who talked less—inverse or antimatching. Participants’ gaze showed the same inverse relation to the confederates’ talk. Requiring gaze to be directed toward a confederate for delivery of approval made no difference in the results. The absence of a difference combined with prior research suggests that matching or antimatching in conversations is more likely due to induction than to reinforcement.     

Coordination of Emotions in Mother–Infant Dialogues

Eleven infant–mother dyads in Crete were videod during spontaneous interactions at home, from the second to the sixth month of life. Micro‐analysis was used to investigate‘coordination'and ‘non‐matching’ of facial expressions of emotion. ‘Emotional coordination’ was evaluated with four measures: matching of facial expressions, completion when one responded to the other with ‘pleasure’ or ‘interest’, synchrony by matching frequency of change or rhythm of emotional expressions, and attunement when shifts of emotional intensity of the two partners were in the same direction.‘Emotional non‐matching'was coded when neither the infant nor the mother showed interest in interacting with the other. In emotional coordination or non‐matching between mother and infant, who performed first was also recorded. We obtained evidence of emotional matching, synchrony, and attunement. Importantly, the probability of emotional non‐matching by the infant was higher than the probability of emotional matching and completion, indicating a tendency for thoughtful attention or playful rivalry in the responses of infants, who also initiated emotional matching, completion, and non‐matching more frequently than mothers. The probability of expression of emotional matching, completion, and non‐matching changed with age. Both mothers and infants act to obtain sympathetic complementarity of feelings and co‐operative inter‐synchrony of actions. Copyright © 2016 John Wiley & Sons, Ltd.     

ELECTROPHYSIOLOGICAL CORRELATES OF STIMULUS EQUIVALENCE PROCESSES

Research reported here concerns neural processes relating to stimulus equivalence class formation. In Experiment 1, two types of word pairs were presented successively to normally capable adults. In one type, the words had related usage in English (e.g., uncle, aunt). In the other, the two words were not typically related in their usage (e.g., wrist, corn). For pairs of both types, event‐related cortical potentials were recorded during and immediately after the presentation of the second word. The obtained waveforms differentiated these two types of pairs. For the unrelated pairs, the waveforms were significantly more negative about 400 ms after the second word was presented, thus replicating the “N400” phenomenon of the cognitive neuroscience literature. In addition, there was a strong positive‐tending wave form difference post‐stimulus presentation (peaked at about 500 ms) that also differentiated the unrelated from related stimulus pairs. In Experiment 2, the procedures were extended to study arbitrary stimulus—stimulus relations established via matching‐to‐sample training. Participants were experimentally näive adults. Sample stimuli (Set A) were trigrams, and comparison stimuli (Sets B, C, D, E, and F) were nonrepresentative forms. Behavioral tests evaluated potentially emergent equivalence relations (i.e., BD, DF, CE, etc.). All participants exhibited classes consistent with the arbitrary matching training. They were also exposed also to an event‐related potential procedure like that used in Experiment 1. Some received the ERP procedure before equivalence tests and some after. Only those participants who received ERP procedures after equivalence tests exhibited robust N400 differentiation initially. The positivity observed in Experiment 1 was absent for all participants. These results support speculations that equivalence tests may provide contextual support for the formation of equivalence classes including those that emerge gradually during testing.