Choice as a function of local versus molar reinforcement contingencies.

Rats were trained on a discrete-trial probability learning task. In Experiment 1, the molar reinforcement probabilities for the two response alternatives were equal, and the local contingencies of reinforcement differentially reinforced a win-stay, lose-shift response pattern. The win-stay portion was learned substantially more easily and appeared from the outset of training, suggesting that its occurrence did not depend upon discrimination of the local contingencies but rather only upon simple strengthening effects of individual reinforcements. Control by both types of local contingencies decreased with increases in the intertrial interval, although some control remained with intertrial intervals as long as 30 s. In Experiment 2, the local contingencies always favored win-shift and lose-shift response patterns but were asymmetrical for the two responses, causing the molar reinforcement rates for the two responses to differ. Some learning of the alternation pattern occurred with short intertrial intervals, although win-stay behavior occurred for some subjects. The local reinforcement contingencies were discriminated poorly with longer intertrial intervals. In the absence of control by the local contingencies, choice proportion was determined by the molar contingencies, as indicated by high exponent values for the generalized matching law with long intertrial intervals, and lower values with short intertrial intervals. The results show that when molar contingencies of reinforcement and local contingencies are in opposition, both may have independent roles. Control by molar contingencies cannot generally be explained by local contingencies.     

Facilitation and helplessness: The interaction of perceived difficulty and importance of a task

Experimentally induced failure sometimes produces helplessness and sometimes facilitation on subsequent tasks. A model which accounts for this in terms of variations in perceived task difficulty and importance and variations in the cost of effort is proposed. Predictions from the model were confirmed in two experiments using the finger shuttlebox. When subjects expected the test task to be easy, importance of test outcome did not affect performance. However, when they expected the test task to be difficult, low outcome importance led to debilitation, and high importance to facilitation. If, in this condition, subjects experienced initial failure on the task perceived as difficult and important, helplessness rather than facilitation was observed. The model proposed may account for some of the conflicting results obtained in laboratory studies of human helplessness.     

Pupillary attributions of college students to happy and angry faces.

As evidence for an hypothesis that pupil size plays an important role in nonverbal communication, Hess (1975) has reported that adults draw in appropriately sized pupils on his happy and angry faces task. However, he did not report a statistical test of his data. In this study, we replicated Hess' research and found congruent with his hypothesis that college students (n = 223) draw in significantly larger pupils on the happy face.     

A multi-element analysis of the effect of teacher aides in an "open"-style classroom

Open classrooms with few rules, individualized instruction, and informal class organization present new problems for the application of behavior principles. The effects of three types of teacher aides on student achievement and on-task behavior were studied. Each was compared with a standard no-aide condition. Subjects were 54 third graders in two "open"-style classrooms. The three types of aide, helping adult, disciplinary adult, and helping fifth-grade aide, were compared in a multi-element design with a no-aide control. The helping-adult aide significantly affected the academic output of the class, when compared with the no-aide condition. All aide conditions produced more academic work and on-task behavior than did the standard no-aide condition.     

Development of an on-line problem-oriented system for the evaluation of mental health treatment services

Current on-line assessment applications are limited to mimicking instruments designed for paper and pencil. The development of an instrument designed specifically for on-line technology is described. The instrument provides research data on treatment effectiveness, clinical information for treatment planning, and management information for resource allocation.     

The perception of stop consonant voicing by Spanish-English bilinguals

The performance of Spanish-English bilinguals in two perception tasks, using a synthetic speech continuum varying in voice onset time, was compared with the performance of Spanish and English monolinguals. Voice onset time in speech production was also compared between these groups. Results in perception of bilinguals differed from that of both monolingual groups. Results of bilingual production in their two languages conformed with results obtained from each monolingual group. The perceptual results are interpreted in terms of differences in the use of available acoustic cues by bilingual and monolingual listeners of English and Spanish.     

Short-term retention of response outcome as a determinant of serial reversal learning

The correlation between short-term retention of the outcome of the preceding response and overall learning proficiency was investigated for serial reversal learning. Pigeons were trained to asymptote on a serial reversal problem and then were presented a percentage reinforcement schedule where only some correct trials were rewarded. Nonrewarded correct trials were treated exactly as incorrect trials. The difference in error probability following the two types of correct trials was then used as a measure of short-term retention. When intertrial intervals (ITI) were short (6 sec), substantial differences occurred. When the ITI's were increased, the difference in accuracy declined regularly to no difference at an ITI of 60 sec. This demonstration of a short-term retention gradient, coupled with the finding that overall reversal learning was much better with the shorter ITI's, suggests that a primary mechanism of improvement in serial reversal learning is the acquisition of a conditional discrimination based on the outcome of the preceding response.