EFFECT OF SUPPORTED EMPLOYMENT ON THE VOCATIONAL OUTCOMES OF PERSONS WITH TRAUMATIC BRAIN INJURY

This paper reports the job placement of 5 males with severe traumatic brain injury. An individual placement model of supported employment was used. All individuals were placed in competitive employment and received staggered intervention over time by trained employment specialists. A multiple baseline design across persons was used to evaluate results. All individuals had been unable to work consistently or at all in competitive work environments. The range of wages was $4.25 to $5.00 per hour with an average of 339 hours of employment specialist intervention time required per case. The major problems experienced by employment specialists were insubordinate and disruptive behaviors as well as other inappropriate social behaviors displayed at the job site.     

Discriminant analysis of gross and fine motor proficiency data

Two classes of non-handicapped and two classes of handicapped children (n = 67), aged 5 to 12 years, took part in a study designed to determine whether a regular or specially designed physical education program suited their individual needs best. Initially receiving instruction with class peers each child was administered the 14-item short-form Bruininks-Oseretsky Test of Motor Proficiency. Discriminant analysis of the data indicated that two of the three functions were significant, together accounting for 93% of the variance. For each significant function fewer than half the test items contributed substantial discriminatory power. Over-all, 75% of the subjects were correctly classified but misclassifications occurred in each class; different placements seem appropriate for non-handicapped and handicapped children.     

Dissociable learning processes in comparative psychology

Comparative and cognitive psychologists interpret performance in different ways. Animal researchers invoke a dominant construct of associative learning. Human researchers acknowledge humans’ capacity for explicit-declarative cognition. This article offers a way to bridge a divide that defeats productive cross-talk. We show that animals often challenge the associative-learning construct, and that it does not work to try to stretch the associative-learning construct to encompass these performances. This approach thins and impoverishes that important construct. We describe an alternative approach that restrains the construct of associative learning by giving it a clear operational definition. We apply this approach in several comparative domains to show that different task variants change—in concert—the level of awareness, the declarative nature of knowledge, the dimensional breadth of knowledge, and the brain systems that organize learning. These changes reveal dissociable learning processes that a unitary associative construct cannot explain but a neural-systems framework can explain. These changes define the limit of associative learning and the threshold of explicit cognition. The neural-systems framework can broaden empirical horizons in comparative psychology. It can offer animal models of explicit cognition to cognitive researchers and neuroscientists. It can offer simple behavioral paradigms for exploring explicit cognition to developmental researchers. It can enliven the synergy between human and animal research, promising a productive future for both.     

Multidimensional processing of dynamic sounds: more than meets the ear

Strong cross-modal interactions exist between visual and auditory processing. The relative contributions of perceptual versus decision-related processes to such interactions are only beginning to be understood. We used methodological and statistical approaches to control for potential decision-related contributions such as response interference, decisional criterion shift, and strategy selection. Participants were presented with rising-, falling-, and constant-amplitude sounds and were asked to detect change (increase or decrease) in sound amplitude while ignoring an irrelevant visual cue of a disk that grew, shrank, or stayed constant in size. Across two experiments, testing context was manipulated by varying the grouping of visual cues during testing, and cross-modal congruency showed independent perceptual and decision-related effects. Whereas a change in testing context greatly affected criterion shifts, cross-modal effects on perceptual sensitivity remained relatively consistent. In general, participants were more sensitive to increases in sound amplitude and less sensitive to sounds paired with dynamic visual cues. As compared with incongruent visual cues, congruent cues enhanced detection of amplitude decreases, but not increases. These findings suggest that the relative contributions of perceptual and decisional processing and the impacts of these processes on cross-modal interactions can vary significantly depending on asymmetries in within-modal processing, as well as consistencies in cross-modal dynamics.     

Measures of temporal discrimination in fixed-interval performance: A case study in archiving data

The primary data of many experimental studies of animal learning and performance consist of the times at which stimuli and reinforcers were delivered, and the times at which responses occurred. The articles based on most of these studies report selected data, either from some sessions or some animals, or summary measures of the animals’ behavior. The primary data are sufficient to produce any of the selected and summary measures, but the selected and summarized data cannot produce many of the measures used in other experimental reports. It is now feasible to archive the primary data from animal behavior experiments so that they are accessible for others to perform secondary analysis. The value of such secondary analysis of archived data is described with a case study in which rats were trained on three fixed-interval schedules of reinforcement. The full data set may be downloaded fromwww.psychonomic.org/archive/.