Escape from serial stimuli leading to food

If the functional relations governing the strength of a conditioned reinforcer correspond to those obtained with other Pavlovian procedures (e.g., Kaplan, 1984), the termination of stimuli appearing early in the interval between successive food deliveries should be reinforcing. During initial training we presented four key colors, followed by food, in a recurrent sequence to each of 6 pigeons. This established a baseline level of autoshaped pecking. In later sessions, we terminated each of these colors or only the first color for a brief period following each peck, replacing the original color with a standard substitute to avoid darkening the key. Pecking decreased in the presence of the last color in the sequence but increased in the presence of the first. In accord with contemporary models of Pavlovian conditioning, these and other data suggest that the behavioral effects of stimuli in a chain may be better understood in terms of what each stimulus predicts, as measured by relative time to the terminal reinforcer, than in the exclusively positive terms of the traditional formulation (Skinner, 1938). The same model may also account for the initial pause under fixed-interval and fixed-ratio schedules of reinforcement.     

Construct validity of four basic Vocational Interest factors

To find evidence of the generalizability of four interest factors established for tests within the Roe-Holland framework, factor scores derived from a Vocational Interest Inventory grounded in Roe's system were correlated with the empirically based Strong-Campbell Occupational scale scores. For this sample of 300 counseling clients, a majority of the hypothesized relations were found, and arranging the occupations along these bipolar dimensions both sharpened the definitions of the factors and provided an additional interpretive aid for counseling.     

GENERALIZATION EFFECTS FROM INTRATHERAPY ARTICULATION TRAINING: A CASE STUDY1

This study analyzed generalization effects found associated with a language-training intervention to modify the articulation (/f/ phoneme) of a 3.5-year-old boy. The McLean and Raymore Stimulus Shift Articulation Program was implemented by the subject's mother. This language training program is designed to produce setting generalization effects based on an intratherapy training model (i.e., systematic training is applied in a single setting to promote transfer effects to nontraining environments). The intervention resulted in a significant improvement in the subject's production of the /f/ phoneme within the clinical setting in response to untrained stimuli (stimulus generalization). Additionally, the subject's correct phoneme production was observed to generalize to his home and school settings (setting generalization) under “opportunity loaded” (picture prompts) and “spontaneous” (no prompts) conditions. The results provide case-study evidence that stimulus generalization, both within and across settings, may occur with exclusively intratherapy articulation training.     

Schedule thinning following communication training: using competing stimuli to enhance tolerance to decrements in reinforcer density

Functional communication training (FCT) is a widely used treatment for individuals with developmental disabilities who exhibit severe behavior problems. One inherent challenge of employing FCT as a treatment in the community is that reinforcement for appropriate communication cannot always be immediate or even possible in some circumstances. Of the few studies that have incorporated some form of schedule thinning for communication, most have reported disruption of communication or increases in problem behavior when the schedule of reinforcement is thinned. In the current study, we compared FCT with extinction to FCT with extinction and access to competing stimuli. After conducting a functional analysis, a competing stimulus assessment was performed to identify stimuli that produce reinforcement that ostensibly competes with reinforcement that maintains problem behavior. It was hypothesized that FCT with competing stimuli would result in more stable reductions in problem behavior during schedule thinning, which would ultimately result in quicker achievement of the treatment goal (low levels of problem behavior under the terminal reinforcement schedule for communication) than FCT without competing stimuli. Results confirmed this hypothesis.     

Piagetian conservation of discrete quantities in bonobos (Pan paniscus), chimpanzees (Pan troglodytes), and orangutans (Pongo pygmaeus)

This study investigated whether physical discreteness helps apes to understand the concept of Piagetian conservation (i.e. the invariance of quantities). Subjects were four bonobos, three chimpanzees, and five orangutans. Apes were tested on their ability to conserve discrete/continuous quantities in an over-conservation procedure in which two unequal quantities of edible rewards underwent various transformations in front of subjects. Subjects were examined to determine whether they could track the larger quantity of reward after the transformation. Comparison between the two types of conservation revealed that tests with bonobos supported the discreteness hypothesis. Bonobos, but neither chimpanzees nor orangutans, performed significantly better with discrete quantities than with continuous ones. The results suggest that at least bonobos could benefit from the discreteness of stimuli in their acquisition of conservation skills.     

Teaching children with autism spectrum disorder to tact auditory stimuli: A replication

It is important that tacts are controlled by stimuli across all senses but teaching tacts to children with autism spectrum disorder (ASD) is often limited to visual stimuli. This study replicated and extended a study on the effects of antecedent-stimulus presentations on the acquisition of auditory tacts. We used a concurrent multiple probe across sets design and an embedded adapted alternating treatments design to evaluate acquisition of auditory tacts when auditory stimuli were presented alone (i.e., isolated) or with corresponding pictures (i.e., compound-with-known and compound-with-unknown) with two school-aged boys with ASD. Both participants' responding met the mastery criterion no matter the stimulus presentation with at least one set, but one participant failed to acquire one set of stimuli in the isolated condition. The isolated condition was rarely the most efficient. We conducted post-training stimulus-control probes, and we observed disrupted stimulus control in the isolated condition for one participant. Implications for arranging auditory tacts instruction are discussed.     

EFFECTS OF WARNING STIMULI FOR REINFORCER WITHDRAWAL AND TASK ONSET ON SELF-INJURY

Results of a functional analysis of self-injurious behavior (SIB) in a child with autism showed that her SIB was maintained by access to preferred objects and escape or avoidance of task demands. Extinction and noncontingent reinforcement treatments were supplemented by presenting a statement combined with a picture cue at 30-s intervals indicating that a preferred object would be removed or a task would be presented. Warning stimuli in combination with extinction and noncontingent reinforcement reduced SIB to acceptable levels. SIB rates remained comparatively high in a control condition consisting of a 2-min delay to onset of reinforcer removal or task demands.     

Hermeneutics and Experiences of the Body. The Case of Low Back Pain

The purpose of this paper is to elaborate on the notion of clinical medicine as a hermeneutical enterprise and to bridge the gap between the general perspectives of hermeneutics and the particularities of medical practice. The case of a patient with low back pain is analyzed. The discussion centers around the metaphor of the patient as a text and a model of five social discourses about low back pain. The problems addressed are: (1) the nature of a moral experience, (2) the variety of available texts, (3) the difference between the doctor's and patient's narratives, and (4) the patient's and doctor's responsibility regarding the existential, biographical meaning of an illness. Although many problems are left unsolved, it is argued that from a philosophical point of view the notion of medicine as a hermeneutical enterprise opens up the possibility of gaining insight in the foundations of the clinical encounter.     

The effects of speech output technology in the learning of graphic symbols

The effects of auditory stimuli in the form of synthetic speech output on the learning of graphic symbols were evaluated. Three adults with severe to profound mental retardation and communication impairments were taught to point to lexigrams when presented with words under two conditions. In the first condition, participants used a voice output communication aid to receive synthetic speech as antecedent and consequent stimuli. In the second condition, with a nonelectronic communications board, participants did not receive synthetic speech. A parallel treatments design was used to evaluate the effects of the synthetic speech output as an added component of the augmentative and alternative communication system. The 3 participants reached criterion when not provided with the auditory stimuli. Although 2 participants also reached criterion when not provided with the auditory stimuli, the addition of auditory stimuli resulted in more efficient learning and a decreased error rate. Maintenance results, however, indicated no differences between conditions. Finding suggest that auditory stimuli in the form of synthetic speech contribute to the efficient acquisition of graphic communication symbols.     

Serial conditioning as a function of stimulus, response, and temporal dependencies

Six experiments were used to examine the effects of explicit response, stimulus, and temporal dependencies on responding in an interfood interval. The first two experiments demonstrated that 10-segment 60-s interfood clocks controlled similar distributions of key pecking in pigeons regardless of whether response–reinforcement contiguity was required, allowed, or precluded. The third and fourth experiments found that in the absence of an explicit response–reinforcement dependency, systematic explicit stimuli in an interfood interval were sufficient to establish and maintain the characteristic distribution of key pecking and that an interval without an explicit clock failed to establish or maintain key pecking. The last two experiments demonstrated that the interfood interval need not be of fixed length, and that a simple correlation of stimuli with increments from either a minimum to a maximum imminency or probability of food presentation controlled behavior in a similar manner. Successively higher rates generally occurred to successively later stimuli in the upper half of the range.