EVIDENCE FOR RELATIONAL-CODING IN CONCEPT FORMATION,AND A NOTE ON THE EFFECTS OF FEEDBACK*

The purpose of the present paper was to determine whether people encode relations among component features in experience, or whether they simply encode the occurrence of features separately as independent cues. This has become a major issue in theories of concept-formation at the present time. It is suggested in this paper that two problems have particularly obstructed a clear resolution of the issue. The first is a consistent failure to check to what extent training materials actually contain relations among features, before results are declared in favour of a particular model. The second is the use, hitherto, of only informal methods of analysing such relations, where they exist, and of predicting from them the structure of the concept. This paper describes an expression for measuring the overall relations among feature-variables in concept training materials. It also introduces a methodology, using log-linear models, for predicting concept structures on the basis of those relations. An experiment combined these methods to assess whether subjects abstracted relations among features, or whether they abstracted independent cues. A subsidiary aim was to assess how feedback, based on independent-cue information, during learning, affected the construction of the concept. The results came out strongly in favour of relational-coding and there was some evidence that feedback based on independent-cues retarded concept formation.     

Eye movements and the perceptual span in beginning and skilled readers

Four experiments are reported which examined the size of the perceptual span in second-, fourth-, and sixth-grade children, as well as adult skilled readers. The results indicated that the perceptual span in beginning readers is slightly smaller than the perceptual span of skilled readers. Using a moving window technique, it was found that the perceptual span of beginning readers extends about 11 character spaces to the right of fixation; for skilled readers, the span extends 14-15 spaces to the right of fixation. Beginning readers apparently devote more of their processing to the foveally fixated word than more proficient readers, but their perceptual span appears to be asymmetric to the right of fixation as is the case for skilled readers. The results of the experiments also indicated that the size of the perceptual span is variable and can be influenced by the difficulty of the text. It is concluded that the size of the perceptual span does not cause beginning readers' slow reading rates.     

Altruism and aggression: the heritability of individual differences

Five questionnaires measuring altruistic and aggressive tendencies were completed by 573 adult twin pairs of both sexes from the University of London Institute of Psychiatry Volunteer Twin Register. The questionnaires measured altruism, empathy, nurturance, aggressiveness, and assertiveness. The intraclass correlations for the five scales, respectively, were .53, .54, .49, .40, and .52 for 296 monozygotic pairs, and .25, .20, .14, .04, and .20 for 179 same-sex dizygotic pairs, resulting in broad heritability estimates of 56%, 68%, 70%, 72%, and 64%. Additional analyses, using maximum-likelihood model-fitting, revealed approximately 50% of the variance on each scale to be associated with genetic effects, virtually 0% with the twins' common environment, and the remaining 50% with each twins' specific environment and/or error associated with the test. Correcting for the unreliability in the tests raised the maximum-likelihood heritabilities to approximately 60%. Age and sex differences were also found: altruism increased over the age span from 19 to 60, whereas aggressiveness decreased, and, at each age, women had higher scores than men on altruism and lower scores on aggressiveness.     

The effect of negative stimulus presentations on observing-response rates

Theories of observing differ in predicting whether or not a signal for absence of reinforcement (S−) is capable of reinforcing observing responses. Experiments in which S− was first removed from and then restored to the procedure have yielded mixed results. The present experiments suggest that failure to control for the direct effect of presenting S− may have been responsible. Pigeons and operant procedures were used. Experiment 1 showed that presentations of S−, even when not contingent on observing, can raise the rate of an observing response that was reinforced only by presentations of a signal (S+) that accompanied a schedule of food delivery. Experiment 2 showed that this effect resulted from bursts of responding that followed offsets of S−. Experiment 3 showed that, when the presence of S− was held constant, lower rates occurred when S− was dependent on, rather than independent of, observing. These results support theories that characterize S− as incapable of reinforcing observing responses.     

Exceptional musical performance in early childhood catatonia

Many years ago the author, jointly with a psychologist, described a patient who, in spite of her alleged idiocy, showed an exceptional musical capacity. However, in the meantime the author has recognized and described early childhood catatonics and, as a consequence of this new knowledge, he has to admit an error. Even according to our then findings it would have been identifiable that, as has been confirmed now by follow-up, the patient is suffering from catatonia, starting in infancy. The high musical performance, then arousing our greatest astonishment, is now explicable, for childhood schizophrenics do not develop general mental deficiency but only specific circumscribed deficits.     

Has the cataphasic form of schizophrenia increased in modern times?

According to our investigations the incidence of cataphasia, which is a subtype of schizophrenia, has become more common in the last years and on average, has started earlier in life. As the central disorder of this illness concerns thinking perhaps there exists a relation of our finding to the rapid modern development of techniques, insofar as the cognitive function is overstrained in childhood and adolescence, when the nervous system has not matured yet. Introverted individuals seem to be at a particular risk. However, it must not be disregarded that cataphasia is an inherited illness which cannot be caused by external influences, but can only be promoted in its manifestation.     

Communication-promoting exercise therapy in a closed male psychiatric ward

The use of the communication-promoting gesture therapy in a locked psychiatric men's ward led to the result, that a part of the restlessness and aggression potential of the patients could be commuted into a constructive social behaviour. Simultaneous increased frankness and confidence of patients in physicians and male nurses. A tied group doesn't seem to be a condition for that.