Speech comprehension after unilateral injection of sodium amytal

A unilateral cerebral dominance model predicts that speech comprehension will be disrupted after injection of sodium amytal into one hemisphere but not after the other. This model was supported when an auditory receptive task involving relatively nonredundant stimuli similar to that contained in the Token Test (E. DeRenzi & L. Vignolo, 1962, Brain, 85, 665–687) was administered to 17 epileptic patients undergoing bilateral amytal injections.     

Models of central capacity and concurrency

According to single channel theory, the ability of humans to perform concurrent mental operations is limited by the capacity of a central mechanism. The theory was developed by analogy with early computers which had a single central processing unit and required sequential processing. These limitations are not likely to be properties of the mind. But now computers have begun to employ extensive concurrent processing, because of the decreasing cost of the necessary hardware. In this review we will try to bring the computer analogy up to date. Theoretical issues important for concurrent systems may be of interest to psychologists and have applications to such problems as the speed-accuracy trade-off. Several hypotheses about the way signals gain access to the central mechanism are reviewed. Recent variations of the single channel theory are discussed, including the hypotheses that more than one process can use the central mechanism at a time, and that some processes do not use the central mechanism and can be executed concurrently with those that do. In addition, relevant concepts from scheduling theory and operating systems theory are introduced and difficulties encountered by concurrent systems, namely complexity, deadlocks, and thrashing, are discussed.     

AN ALTERNATING TREATMENTS COMPARISON OF ORAL AND TOTAL COMMUNICATION TRAINING WITH MINIMALLY VERBAL RETARDED CHILDREN

This study was a comparison of the effects of oral speech with total communication (speech plus sign language) training on the ability of mentally retarded children to repeat 4-word sentences. Three children were chosen who used single words to communicate but who did not combine words into complete sentences. Three sentence pairs were trained, with each pair having one sentence trained using oral methods and an equivalent one trained using the total communication approach. Both training procedures involved chaining sentence parts, reinforcement, and prompting. Oral methods involved presenting vocal stimuli and requiring vocal responses whereas total communication methods involved presenting vocal and signed stimuli and requiring vocal and signed responses. For the initial sentence pair with each child, an alternating treatments design was used to determine the relative efficacy of the two language training approaches. This was repeated with a second and third sentence pair using a multiprobe technique within a multiple baseline design. Results pointed to the superiority of the total communication approach in facilitating sentence repetition. Possible explanations of these results are offered and the utility of the alternating treatments experimental design is discussed.     

Delayed reinforcement as an indiscriminable contingency in verbal/nonverbal correspondence training

We investigated the programming of generalization and maintenance of correspondence between verbal and nonverbal behavior in a preschool setting. Four children participated in a series of multiple-baseline designs. In Experiment 1, delayed reinforcement of verbal behavior effectively controlled maintenance of correspondence with previously trained responses and also resulted in generalization of correspondence to one untrained response. As the latter effect was limited, Experiment 2 was a further assessment of the effects of delayed reinforcement of generalization of correspondence to untrained responses, and consistent generalization was shown. Experiment 2 also showed that generalization, if lost, could be recovered through use of "booster training," in which the original contingencies were reinstated for a brief period. Experiment 3 provided replications, with two additional children, of the effects of delayed reinforcement on maintenance of correspondence. Results are discussed in terms of using delayed reinforcement as an indiscriminable contingency.     

Further evaluation of prompt density,rate of reinforcement,and the persistence of manding

Previous research has evaluated the effects of prompt rates on the rate of communicative behavior. More recent research has suggested that dense prompting can result in communicative behavior that is more resistant to change. However, existing research has not considered the impact that higher response rates had on reinforcement rate, a variable known to impact response persistence. The current study systematically replicated previous research by evaluating communicative responding in contexts associated with dense- and lean-prompt schedules and extended existing research by (a) holding reinforcement rates similar across the two prompting schedules (lean and dense), and (b) evaluating the persistence of communicative responding in the contexts associated with each prompting schedule. The results for Experiment 1 clearly replicated and extended previous research. The results for Experiment 2 were equivocal and suggested that previous reinforcement history and response class size impacted outcomes.     

Teaching self-control to reduce overt food stealing by children with autism and developmental disorders

Food stealing is often a serious behavioral problem among children with diagnoses of autism and other developmental disorders. Very few empirical studies concerning this behavioral challenge have been reported. We applied a correspondence training procedure to teach self-control as replacement behavior to four children with autism and developmental disorders who displayed food stealing in the community. A changing criterion design embedded within a nonconcurrent multiple-probe across participants design was used. The treatment succeeded for all four participants by increasing latency to eating highly preferred food to a predetermined criterion and reducing occurrences of food stealing to zero. Three participants generalized the replacement behavior to natural settings and maintained the behavior for 2 weeks, 1 month, 2 months, 3 months, and 4 months. One participant without expressive language was taught successfully during treatment trials but failed to maintain and generalize the behavior. A functional relation between delaying food eating and Say-Do correspondence training was demonstrated.     

Comparison of two video prompting interventions to teach daily living skills to adolescents with autism

The present study used an adapted alternating treatment design to evaluate and compare the effects of video prompting (VP) and video prompting plus frequency building (VP + FB) to teach daily living skills to three adolescents with autism spectrum disorder. Results demonstrated all three students made substantial improvements over their baseline performance using VP and VP + FB. Furthermore, a strong intervention effect emerged for VP and VP + FB conditions when compared to the control task. However, in terms of one intervention proving superior to the other (e.g., VP to VP + FB), the data offer a mixed interpretation with VP + FB affecting changes better for two of the three students. The FB component in the VP + FB produced strong, consistent gains for all students in terms of retention.     

Telehealth parent training for a young child at risk for autism spectrum disorder

The global pandemic has highlighted the importance of telehealth to access behavioral interventions. Face-to-face parent training improves the development and behaviors of young children at risk for autism spectrum disorder (ASD). We evaluated a telehealth parent training intervention for a child at risk for ASD. Two parents identified possible early ASD symptoms in their 30-month-old son (lack of imitation, pointing, and vocal manding). Both parents simultaneously received telehealth behavioral skills training on the Parent Intervention for Children at Risk for Autism program for 1 hour per week over 29 weeks. Multiple baseline designs across parent and child behaviors showed that both parents improved their parent teaching fidelity above 80% and the child improved on all trained behaviors. This study expands the utility of telehealth behavioral parent training to young children at risk for ASD to mitigate early symptoms of ASD.