Analysis and Intervention in Developmental Disabilities最新文献

To determine how stimulus control of eye orientation was established and how that process affected learning, an analysis of normal preschool children's eye orientations and pointing responses to each of two simultaneously presented stimuli (S+ and S-) was conducted. Using a probe design to test for acquisition, each subject was trained on two tasks. In one task, S+ (selections of this stimulus produced reinforcement) was held constant at the final criterion level while S- (selections of this stimulus never produced reinforcement) was manipulated using stimulus shaping procedures. The second task was programmed with the opposite method (S+ shaped while S- held constant). Results showed that more pointing response errors, more occurences of eye orientations, and longer durations of eye orientations characterized conditions where S+ was held constant and S- was shaped. The individual analysis of the eye orientation data indicated that differences in eye orientation to stimuli under the two programs were largely due to relatively higher frequency of orientation to the S- stimulus under program condtions that shaped S- and held S+ constant.

Graduated stimulus change and trial-and-error methods were used to train a two- choice discrimination task to two groups of profoundly retarded individuals. The results were compared across four size- and four shape-discrimination tasks. Graduated stimulus change was more efficient than trial-and-error on the initial problem, continued to be more efficient across tasks, and was more efficient on two reversal problems. However, experience with similar problems was shown to be an important factor.

This experiment evaluated parent and teacher use of reinforcement-based, reductive procedures to treat aggressive pinching in a severely retarded child. A withdrawal and a multiple baseline design were used for the analysis. Substantial and lasting treatment effects were obtained at home and school. The benefits and problems associated with parent use of reinforcement-based, behavioral procedures with severely handicapped children, as well as the comparative effects of DRO and DRI are discussed.

A stimulus-equivalence paradigm was used to establish match-to-sample relations between members of two separate stimulus classes through a procedure involving direct training and observational learning. Four retarded adult males were taught to conditionally match arbitrary visual stimuli. Each subject was taught one sample- comparison relation within each class (e.g., B1A1, B2A2) and given an opportunity to observe another subject perform a second sample-comparison relation within each class (e.g., C1A1, C2A2); each observed relation had one stimulus in common with a sample-comparison relation acquired through direct training (A1, A2). When subjects acquired the trained and observed relations, they were tested on the sample-comparison relations that were never taught directly (AB, AC, CB, BC). Initial testing on the BC and CB relations revealed chance performance for two subjects. Subsequent testing on the AB and AC relations, however, resulted in immediate acquisition of the CB and BC derived relations. Results indicated that stimulus-equivalence teaching procedures used in academic group settings have promising educational implications for producing learning through observation of others.

Two normal children and four retarded youths were taught auditory-visual and visual-visual conditional discriminations and were then tested to determine whether the conditional relations were also equivalence relations. All subjects showed that conditionally related sample and comparison stimuli had become equivalent; the conditional discriminations generated two sets of three-member classes, one set containing both auditory and visual stimuli and the other containing only visual stimuli. In the auditory-visual classes, two of the retarded subjects failed to apply the name of the auditory stimulus to each visual stimulus in the same class; in the visual classes, all but one normal subject failed to apply a consistent label to all stimuli in a class. The formation of classes of equivalent stimuli does not, therefore, require that common names be applied to each member of a class. Although common naming responses were not necessary for equivalence, relations denoting symmetry and transitivity in the original conditional discriminations were shown to be prerequisites, as is demanded by the definition of equivalence.

Five rehabilitation clients were trained to use written prompts to (a) plan nutritious meals for 1 week, (b) write accurate grocery lists based on their menus, (c) stay within a $25.00 weekly food budget, and (d) shop effectively and systematically. Training occurred in a classroom using group instruction for the first three response classes above. The shopping response classes were trained in a community grocery store. Training consisted of experimenter modeling, subject rehearsal, as well as experimenter and peer feedback in a multiple probe design. Subjects' meal plans were nutritionally deficient in three of the four food groups during baseline, but met or exceeded the four food group criterion after instruction. Grocery list writing skills improved from a mean of less than 30% correct during baseline to more than 90% correct after training. Similarly, subjects' grocery lists cost an average of 72% over the $25.00 budget before training, and 19% under the budget after training. Subjects' mean percent of effective and systematic shopping increased to 91% and 100%, respectively, following instruction. Generalization of shopping skills from the training store to two stores in which no training occurred was observed. Follow-up tests for all subjects as well as community probes for two subjects living independently showed that all skills maintained at acceptable levels.

Little is known about the acquisition of stimulus control in autistic children. Many studies comment on the incidental, unintended, and often bizarre stimulus control acquired when normal discrimination learning procedures are used. Earlier studies suggested the problem may involve autistic children's inability to respond to multiple, simultaneous cues. While this has been clearly demonstrated in some instances, subsequent data have shown that autistic children sometimes do respond to multiple cues. The question remains, then: What variables influence stimulus control in autistic children? The present study examined one alternative, the possible effects of the absolute distance between cues, in an attempt to better understand (and program) stimulus control in autistic children. Three autistic children were trained to select a card containing a stimulus array comprised of three visual cues. The distance of each cue from the center cue was varied, using small, medium and large distance conditions. Stimulus control probes were conducted for each distance condition to assess which of the features the children learned about. The results revealed that the absolute distance between the cues determined the number of stimulus features to which the autistic child responded; decreasing the distance between cues served to increase the number of cues that controlled responding. The distances used in this study did not, however, affect the responding of MA-matched and CA-matched normal children. The possible role of “tunnel vision” and “the distance between cues” in treating and understanding autistic children are discussed.

This study evaluated the effects of access to opportunities to earn edibles for performing a high probability stereotypic behavior on the public genital stimulation and stereotypy of a severely retarded male in a special education class. The treatment involved the use of a series of increasing DRO lengths in which the absence of genital stimulation was reinforced with edibles and a stereotypic behavior. Later, we attempted to reduce the rate of stereotypy by withdrawing the edibles that had been provided for it during the reinforcement period. The results indicated that (a) genital stimulation was nearly eliminated with the graduated DRO procedure; (b) withholding the edibles had little effect in reducing the stereotypic behavior; and (c) edibles alone were enough to maintain the reductions in genital stimulation. These findings suggest that public genital stimulation is amenable to treatment with a positive treatment procedure, but more research with the reinforcer displacement technique is needed before any firm conclusions can be drawn about its effectiveness in an applied setting.