Negative reinforcement and choice in humans

Participants chose between reinforcement schedules differing in delay and/or duration of noise offset. In Experiment 1 it was found that (1) immediate reinforcement was preferred to delayed reinforcement when amounts (durations) of reinforcement were equal; (2) a relatively large reinforcer was preferred to a smaller one when both reinforcers were obtained immediately; and (3) preference for an immediate, small reinforcer versus a delayed, large reinforcer increased as the delay preceding the large reinforcer increased, a sign of “impulsivity”. In Experiment 2, the schedules differed in amount or delay and equal intervals were added either to the constant parameter or the varied parameter. A shift from virtually exclusive preference to indifference occurred in the latter case but not the former, a result supporting a model of self-control that assumes that the value of a schedule depends on the ratio of amount and delay, and that choice between schedules depends on the ratio of these values.     

Event-related potential studies of cerebral specialization during reading: I. Studies of normal adults

A number of methodological features were incorporated in a paradigm designed to maximize the likelihood of finding reliable event-related potential (ERP) signs of functional specializations between and within the cerebral hemispheres. Every subject was more accurate in identifying words presented to the right than to the left visual field. The morphology of the ERPs elicited by these words varied considerably as a function of electrode position both within and between the hemispheres. Amplitude asymmetries of ERP components recorded from occipital regions of the two hemispheres varied systematically with the position of the word in the visual field. On the other hand, ERPs from more anterior (temporal and frontal) regions displayed large asymmetries which were in the same direction regardless of the visual field of word presentation. The most prominent such asymmetry was in the negativity in the region 300–500 msec (N410) which was larger in the left than the right hemisphere in every subject. These results demonstrate that in this paradigm which demands specialized language processing ERPs are sensitive to aspects of cerebral organization both within and between the two hemispheres.     

A Chinese perspective on Kohlberg's theory of moral development

This essay uses the Chinese culture as an example to underline the culturally specific contextual problems regarding Kohlberg's theory of moral development and to point to a new direction for cross-cultural research in this area. The Western view of man as an autonomous being who makes free and rational choices as a moral agent is clearly reflected in Kohlberg's stages of moral development as well as his methodology. The Confucian view of man as an integral part of an orderly universe with an innate moral sense to maintain harmony is quite different. Further, the preferred mode of resolving human conflict in China is reconciliation and collective decision making rather than individual choice, commitment, and responsibility as in the West. In the light of these fundamental differences in the two cultural traditions, an alternative to Kohlberg's theory is suggested.     

The use of schemata in the acquisition and transfer of knowledge

A learning model based on “memory schemata” is presented. The model assumes that knowledge substructures in memory are shared by multiple representations of information from diverse contexts. These substructures, or schemata, are collections of concepts and associations that occur together repeatedly and act as unitary, higher-order concepts. When knowledge is represented in terms of a schema, associations from the schema to additional concepts specify the detailed information for that context. This organization of knowledge entails both costs and benefits for the acquisition and retention of new information that utilizes a schema. The use of a familiar encoding structure facilitates memory access at storage and retrieval time. Multiple uses of the shared structure produce interference among concepts from the various contexts. The predictions of the model were tested in two transfer experiments in prose learning. Experiment l demonstrated the simultaneous effects of both facilitation and interference in the learning of diverse information conforming to a single schema. Recall of information from the schema was a non-monotonic function of schema strength. In Experiment 2 facilitation was preserved while interference was eliminated by increasing the discriminability among competing contexts. Results from both experiments confirmed the predictions of the model.     

Linguistic meaning related differences in evoked potential topography: English, Swiss-German, and imagined

Functionally different neural populations for processing different categories of word meaníng are suggested by the topography of event-related EEG scale-field distributions. Noun and verb meanings of English and Swiss-German homophones produced differences in anterior-posterior topography during the first 300 to 350 msec of the response. Similar results were found for a degraded-speech stimulus when subjects imagined noun and verb meanings. Anterior—posterior scalp-field differences appeared both in an analysis of the positions of field maximal and minimal values; and in principal component analysis of ERPs.     

Response and associative phase components of elaborative prompt effects in children's noun-pair learning

The effects of aural and pictorial elaborative prompts were estimated separately for response and associative phase components of children's nounpair learning. A 20-item list of noun pairs was administered individually to 200 second- and third-grade children by the method of paired-associates. Indices of response learning (free verbal recall and pictorial identification) revealed equivalent effects among prompt conditions whereas measures of associative learning (multiple-choice pictorial-recognition tests) demonstrated substantial performance facilitation as a function of both aural and pictorial elaborative prompts. This outcome was regarded as an unequivocal identification of the locus of elaborative prompt effects in children's nounpair learning.