PubMed Health⌕ Search

Biomedical subjects

R Stromer

Publications and source records attributed to R Stromer.

At least 19 recordsLinked to original sources

Integrating basic and applied research and the utility of Lattal and Perone's Handbook of research methods in human operant behavior.

Lattal and Perone's Handbook of methods used in human operant research on behavioral processes will be a valuable resource for researchers who want to bridge laboratory developments with applied study. As a supplemental resource, investigators are also encouraged to examine the series of papers in the Journal of Applied Behavior Analysis that discuss basic research and its potential for application. Increased knowledge of behavioral processes in laboratory research could lead to innovative solutions to practical problems addressed by applied behavior analysts in the home, classroom, clinic, and community.

Behavior Therapy↗

Designing interventions that include delayed reinforcement: implications of recent laboratory research.

UNLABELLED: The search for robust and durable interventions in everyday situations typically involves the use of delayed reinforcers, sometimes delivered well after a target behavior occurs. Integrating the findings from laboratory research on delayed reinforcement can contribute to the design and analysis of those applied interventions. As illustrations, we examine articles from the Journal of the Experimental Analysis of Behavior that analyzed delayed reinforcement with respect to response allocation (A. M. Williams & Lattal, 1999), stimulus chaining (B. A. Williams, 1999), and self-control (Jackson & Hackenberg, 1996). These studies help to clarify the conditions under which delayed reinforcement (a) exercises control of behavior, (b) entails conditioned reinforcement, and (c) displaces the effects of immediate reinforcement. The research has applied implications, including the development of positive social behavior and teaching people to make adaptive choices. DESCRIPTORS: delayed reinforcement, response allocation, stimulus chains, self-control, integration of basic and applied research

Humans↗

Written lists as mediating stimuli in the matching-to-sample performances of individuals with mental retardation.

Students with mental retardation learned to write lists in order to perform a matching task that they could not do otherwise. After an initial assessment phase, reinforcement was arranged in the computerized tasks to follow selection of the six pictures that were identical to those in the six-picture samples presented. In Study 1, even though the participants wrote a list of the names of the six sample pictures on each trial, read a list, or did both, they often made errors when a brief delay preceded picture selection. In contrast, performance was nearly perfect when a list was written, read, and remained available at the time of picture selection, suggesting that the list served to mediate the delays. Study 2 examined the stimulus control by two- and six-picture samples over the list writing. Early during testing, 1 participant refrained from writing lists on two-picture trials but wrote lists on six-picture trials, thereby maximizing reinforcement and minimizing its delay; the other participant showed this pattern of list writing after supplemental training. The studies suggest methods for establishing a rudimentary repertoire of mediating behavior that has relevance for teaching instruction-following skills in natural settings.

Achievement↗

Transitivity and emergent sequence performances in young children.

Children taught to sequence pairs of visual stimuli also performed additional sequences without direct training. In Experiment 1, the children were trained to produce a six-stimulus sequence (A > B > C > D > E > F) with one set of forms, and five overlapping two-stimulus sequences (A > B, B > C, C > D, D > E, and E > F) with another set of forms. Few of the children succeeded on tests for the untrained two- (e.g., B > D and B > E) and six-stimulus sequences derivable from the two-stimulus training. The children in Experiments 2 and 3 received only the overlapping sequence training before testing with refined protocols: Nearly all succeeded on tests of emergent sequences involving two, three, four, five, and six stimuli. The results suggest methods for examining transitive relations between pairs of the stimuli used in training and the development of a relation of order among all six of the stimuli involved.

Chi-Square Distribution↗

Picture naming, matching to sample, and head injury: a stimulus control analysis.

Computer-based procedures were used to examine oral naming and matching-to-sample performances in an adult with a head injury. Relatively few errors occurred when pictures were (a) named, (b) matched to dictated names presented simultaneously, (c) matched to dictation after a delay, and (d) matched to identical pictures presented simultaneously. More errors occurred on delayed than on simultaneous identity matching. On delayed matching trials, fewer errors occurred when instructions to name the samples were given.

Adult↗

Teaching computer-based spelling to individuals with developmental and hearing disabilities: transfer of stimulus control to writing tasks.

Computer-based instruction may yield widely useful handwritten spelling. Illustrative cases involved individuals with mental retardation and hearing impairments. The participant in Study 1 matched computer pictures and printed words to one another but did not spell the words to pictures. Spelling was then taught using a computerized procedure. In general, increases in the accuracy of computer spelling were accompanied by improvements in written spelling to pictures. Study 2 extended these results with a 2nd participant. After initial training, spelling improved in the context of a retrieval task in which the participant (a) wrote a list of the names of objects displayed on a table, (b) selected the objects from a shelf, and (c) returned the objects to the table. Nearly perfect accuracy scores declined on some retrieval trials conducted without a list, suggesting that the list may have served a mediating function during retrieval. Transfer of stimulus control of computer-based teaching to the retrieval task may have been attributable to the existence of stimulus classes involving pictures, objects, and printed words.

Achievement↗

Naming, the formation of stimulus classes, and applied behavior analysis.

The methods used in Sidman's original studies on equivalence classes provide a framework for analyzing functional verbal behavior. Sidman and others have shown how teaching receptive, name-referent matching may produce rudimentary oral reading and word comprehension skills. Eikeseth and Smith (1992) have extended these findings by showing that children with autism may acquire equivalence classes after learning to supply a common oral name to each stimulus in a potential class. A stimulus class analysis suggests ways to examine (a) the problem of programming generalization from teaching situations to other environments, (b) the expansion of the repertoires that occur in those settings, and (c) the use of naming to facilitate these forms of generalization. Such research will help to clarify and extend Horne and Lowe's recent (1996) account of the role of verbal behavior in the formation of stimulus classes.

Attention↗

Delayed matching to complex samples and the formation of stimulus classes in children.

In two experiments (ns = 3 plus a previously tested child, and 2, respectively), children learned delayed matching with complex samples, each consisting of a form and a printed nonsense word. Forms or printed words were comparison stimuli. For form comparisons, selecting the form identical to that in the preceding sample was reinforced. For printed word comparisons, selecting the word identical to that in the preceding sample was reinforced. During testing, the children then matched the forms and printed words to one another. In subsequent training, the samples were (a) old forms combined with new words or (b) old words combined with new forms. Novel matching performances among forms and words appeared across these training phases. Word-form contiguity in a matching-to-sample context may contribute to the formation of classes of stimuli that may be equivalent.

Attention↗

Matching to complex samples and stimulus class formation in adults with autism and young children.

Adults with autism and young children first learned to match one-element comparison stimuli to two-element sample stimuli. Test conditions then examined whether each of the individual sample elements (a) controlled selections of the comparison stimuli to which they were related during training, (b) were interchangeable with one another as either sample or comparison stimuli, and (c) were interchangeable with the original comparison stimuli. Test data were positive and suggested the formation of three-member stimulus classes. Subsequent experiments demonstrated the formation of four-member classes by (a) adding novel stimuli by training outside the original context; (b) adding novel stimulus elements to the two-element samples used during baseline training; and (c) training with three-element rather than two-element sample stimuli from the outset. Results suggest that acquisition of stimulus classes may be one of the benefits of broad rather than restricted attention to the components of complex stimuli.

Adult↗

Sequence learning in individuals with behavioural limitations.

The production of sequences by two mentally retarded adults and a normally capable preschooler was assessed after each was trained to touch five physically dissimilar and nonrepresentative forms in an experimenter-specified order (denoted A1-->A2-->A3-->A4-->A5). Performance on the 10 constituent two-term sequences was examined (e.g. A-->A2, A2-->A3, A1-->A3 and A2-->A4). The probe data were largely consistent with the five-term sequence performance trained explicitly and suggest the formation of stimulus relations based on relative position rather than a rote stimulus-response chain. The procedures and results were replicated with a second five-term sequence (B1-->B2-->B3-->B4-->B5). The subjects' performances were also assessed on trials in which mixtures of the two sets of stimuli were presented as either two-term probes (e.g. A2-->B4 and B2-->A4; with all three subjects) or five-term probes (e.g. A1-->B2-->A3-->B4-->A5; with the two adult subjects). Again, the subjects' performances were consistent with their baseline training. The mixed-probe data extend prior research on sequence production and suggest the formation of classes of mutually substitutable sequence stimuli. The overall findings highlight the importance of experiential variables in the formation of ordinal relations in developmentally limited individuals.

Child, Preschool↗

Assessing control by elements of complex stimuli in delayed matching to sample.

A series of six experiments examined delayed identity matching-to-sample performances of subjects with mental retardation. The stimuli were either one or two simultaneously displayed forms. When the reinforcement contingencies required that only one form exert discriminative control, all subjects achieved high accuracy scores. However, accuracy scores were substantially lower when the contingencies required discriminative control by two forms, suggesting restricted stimulus control. The decline in matching accuracy appeared to reflect selective losses of conditional control by sample stimuli and shifts in control to features of the comparison stimulus displays. The experiments suggest improved techniques for assessing control by complex stimuli and for evaluating the effects of procedures that seek to broaden restricted stimulus control. The results challenge interpretations based on stimulus-generalization decrement or shared attention.

Adolescent↗

Spelling and emergent picture-printed word relations established with delayed identity matching to complex samples.

Students with academic deficits learned delayed matching-to-sample tasks that used complex sample stimuli, each consisting of a picture and a printed word. A touch to the sample complex removed it from the computer display and produced either picture comparisons or a choice pool of letters. If the comparisons were pictures, selecting the picture identical to the preceding sample was reinforced. If the letters appeared, letter-by-letter construction of the preceding printed word sample was reinforced. The procedure engendered new constructed-response spelling performances and arbitrary relations among pictures and printed words in matching to sample. The emergence of relations among different sets of printed words (paired with the same pictures) suggested classes of equivalent stimuli. Outcome tests involving spoken words as sample stimuli suggested expansion of subjects' spelling repertoires and stimulus classes.

Adolescent↗

Formation of arbitrary stimulus classes in matching to complex samples: supplementary data.

A follow-up study of work published in 1990 showed that consistent use of Tone-relevant trials during training and testing baselines contributed to the reliable formation of 5-member stimulus classes during matching to sample. With Tone-irrelevant trials during either training or testing 4 of 12 subjects formed such classes, but none did so when such trials were used in both training and testing baselines. This extends our prior work.

Attention↗

Conditional stimulus control of childrens' sequence production.

Normally capable children were first taught to touch in sequence each of a set of five physically dissimilar stimuli (Sequence A). Another set of stimuli was then used to train sequence B. Next, direct training established conditional control of the production of the A sequence and its reversal: in the presence of one printed word, touching the stimuli in the order A1----A2----A3----A4----A5 was reinforced; in the presence of another word, touching the stimuli in the order A5----A4----A3----A2----A1 was reinforced. During probe sessions, the printed words also exercised conditional control over production of the B sequence and its reversal for five of six subjects, suggesting the formation of stimulus classes. Four of these five subjects also performed mixed sequences under conditional control of the words (e.g., A1----B2----A3----B4----A5 and its reversal), verifying that the stimuli which occupied the same position in each sequence were members of the same class.

Attention↗

Children's identity matching and oddity: assessing control by specific and general sample-comparison relations.

After children in Experiments 1 and 2 learned identity matching or oddity, control by sample-comparison relations was assessed. Tests for generalized control displayed novel samples and two comparison stimuli, one identical to the sample. Specific relations were tested with identical or nonidentical sample-comparison stimuli from one set of stimuli and substitute comparisons from either the other training set or from a novel set. When tests displayed identical stimuli, patterns of comparison selection suggested control by generalized identity and oddity. However, selection patterns varied when stimuli were nonidentical and familiar or novel substitute comparisons were used. Therefore, control by specific relations is not a precondition for generalized identity and oddity. One set of training stimuli was used in Experiment 3, and generalized performances occurred again. Moreover, control by specific relations was shown by the oddity subjects and 2 of 6 identity subjects. Generalized and specific control may therefore exist simultaneously. In Experiment 4, selections were irregular on tests displaying substitute comparisons and samples and familiar comparison stimuli; this finding supported the relational account of specific sample-comparison control found in Experiment 3.

Attention↗

Symmetry of control by exclusion in humans' arbitrary matching to sample.

Normally capable children and adults were taught arbitrary matching of visual sample stimuli and nonidentical visual comparison stimuli: if Sample A1, selecting comparison B1 was reinforced; if A2, selecting B2 was reinforced. Unreinforced tests included (1) those that assessed preferences between novel comparisons when samples were also novel and (2) those that assessed selections of the least-preferred novel comparisons when the alternate comparisons were familiar B or A stimuli. Subjects during the latter tests tended to select the novel comparisons and not the B or A stimuli; these performances supported an inference of control by exclusion. The finding that subjects excluded the A stimuli when they were displayed as comparisons is contrary to previous research and suggests that control by exclusion was symmetrical under these conditions. Preference tests given after exclusion testing suggested that four of six subjects learned new arbitrary matching performances; their selections of the novel comparisons persisted when the basis of exclusion (B or A stimuli) was removed.

Adult↗