Effects of ratio reinforcement schedules on discrimination performance by Japanese monkeys

In Experiment 1, Japanese monkeys were trained on three conditional position-discrimination problems with colors as the conditional cues. Within each session, each problem was presented for two blocks of ten reinforcements; correct responses were reinforced under continuous-reinforcement, fixed-ratio 5, and variable-ratio 5 schedules, each assigned to one of the three problems. The assignment of schedules to problems was rotated a total of three times (15 sessions per assignment) after 30 sessions of acquisition training. Accuracy of discrimination increased to a moderate level with fewer trials under CRF than under ratio schedules. In contrast, the two ratio schedules, fixed and variable, were more effective in maintaining accurate discrimination than was CRF. With further training, as asymptotes were reached, accuracy was less affected by the schedule differences. These results demonstrated an interaction between the effects of reinforcement schedules and the level of acquisition. In Experiment 2, ratio sizes were gradually increased to 30. Discrimination accuracy was maintained until the ratio reached 20; ratio 30 strained the performance. Under FR conditions, accuracy increased as correct choice responses cumulated after reinforcement.     

Multifactorial assessment of reading disability: identifying the best predictors

A multifactorial diagnostic assessment battery was evaluated using data obtained from 105 reading-disabled children and their matched controls (total N = 210). A stepwise discriminant function analysis selected five nonreading measures from among 16 as the best diagnostic predictors of reading disability. These measures included WISC-R Information and Digit Span, self-reported family histories of reading problems, and tests of symbol-processing speed and letter fluency.     

THE EFFECTS OF INDIVIDUAL AND CONTEXTUAL ATTRIBUTES ON THE SIZES OF RECOMMENDED SALARY INCREASES

In a series of experiments, college students, line managers, and compensation managers allocated salary increases to hypothetical job holders who varied in the criticality of their positions for accomplishment of organizational goals, occupational marketability, job performance, personal need for money, and increase in capability since the last performance review. Results indicated that though performance had the largest impact, a number of nonperformance factors also influenced the recommendations. Salary recommendations were lower when constrained by a budget, and performance, growth in capabilities, marketability, and criticality were all significantly related to the magnitudes of suggested increases.     

Temporal proximity and reinforcement sensitivity in multiple schedules

Distributions of reinforcers between two components of multiple variable-interval schedules were varied over a number of conditions. Sensitivity to reinforcement, measured by the exponent of the power function relating ratios of responses in the two components to ratios of reinforcers obtained in the components, did not differ between conditions with 15-s or 60-s component durations. The failure to demonstrate the “short-component effect,” where sensitivity is high for short components, was consistent with reanalysis of previous data. With 60-s components, sensitivity to reinforcement decreased systematically with time since component alternation, and was higher in the first 15-s subinterval of the 60-s component than for the component whose total duration was 15 s. Varying component duration and sampling behavior at different times since component transition may not be equivalent ways of examining the effects of average temporal distance between components.     

Biomagnetism from the neuropsychiatric viewpoint--principles of recent developments in diagnostic procedure

The following survey is intended to demonstrate and discuss some principle problems of biomagnetism and the application in clinical fields. The development of special technical parameters especially by the SQUID method is initiating new possibilities of research and completing the neurobiologically determinated basis and conditions of neuropsychiatric disorders. The Magnetoencephalography (MEG) will be represent an important role of a new functional diagnostic method.     

Infant hypotonia, obesity, hypogenitalism and oligophrenia--new viewpoints on the etiology and symptoms of Prader-Willi syndrome

We present four cases of Prader-Willi syndrome. Two of them have an abnormality of a chromosome 15, the other both show different chromosomal abnormalities. Translocations or deletions were found recently in the bands 15q11/12 in about 60% of the cases of Prader-Willi syndrome. The consequences for diagnosis, symptomatology and genetic counselling of the syndrome are discussed.