Induction by reinforcer schedules.

Traditional strategies for determining whether a reinforcer schedule enhances the occurrence of an activity are reviewed and critically evaluated. A basic assumption underlying these strategies is that it is possible to isolate the effect of reinforcer intermittency on schedule induction. It is concluded that this is not, in fact, possible. An alternative approach is proposed that emphasizes the inductive effects of the reinforcer schedule as a unit and the effects of particular aspects of the reinforcer schedule (e.g., interreinforcer interval, repetition of the reinforcer, reinforcer magnitude).     

Midi-level measurement of social anxiety in psychiatric and non-psychiatric samples

This paper reports the development and assessment of midi-level behavioral measures of social anxiety in the context of two experiments, one studying an analog student sample, the other a psychiatric sample. Judgments on nine categories of clinically practical midi-level behaviors (e.g. Facial Expression, Orienting, Sense of Timing), based on a review of the literature on human ethology and on pilot research, were compared to global judgments of social anxiety and social skill and to physiological arousal. Intraclass correlations exceeded 0.80 for judgments of the global and midi-level behavioral ratings on both samples. Results of correlational analyses indicated that while there were several significant predictors of global skill and anxiety among the midis, the magnitude of the relationship between midis and globals was stronger for the patient than the student sample. Further analyses based on S's heart rate (HR) reactivity suggested that while global ratings did not significantly predict H R in a high social anxiety situation, one midi-level behavioral rating (self-manipulations) did. The clinical utility of the newly developed measures is discussed with particular attention to their practicality for behavior therapy.     

Comprehending homographs in aphasia

This study assessed 13 aphasic subjects' knowledge of the multiple meanings of homographs. The results indicated that the various meanings were less available to aphasic subjects than to normal subjects. In addition, specific meanings became less available as they became less typical although the number of meanings associated with a homograph did not influence performance. Aphasia type also did not influence performance. Performance on the experimental test was significantly correlated with auditory comprehension level and picture naming ability. The results were related to recent findings on semantic organization in aphasia.     

Predicting school performance of preschool children from parent reports

Parents of 391 preschool children ages 49 to 64 months completed a brief developmental inventory as part of a preschool screening program operated by an urban school district. The 28-item developmental inventory assessed adaptive behavior and language development. In addition, preschool children were administered the Minneapolis Preschool Screening Instrument. Teacher ratings of kindergarten performance the following year provided criterion data to validate the screening measures. Correlations with the overall teacher rating [the mean of nine ratings] were .40 for the adaptive behavior scale and .57 for the language scale. Validity figures for the developmental inventory were significantly higher for low SES than for high SES children, for older children [57 to 64 months] than for younger children [49 to 56 months], and for firstborn children than for younger siblings. No effects were found by sex. While a positive relationship between parent reports of developmental functioning and early school performance was clearly established, validity levels did not justify use of parent information as a sole source of preschool screening information.This research was supported in part by a grant from the Bureau of Education for the Handicapped.     

The case of the disappearing disagreements: A reply to Yussen

S. R. Yussen (1984, Developmental Review, 4, 139–144) and I have few disagreements. The major one seems to be in what the purpose of my article (R. J. Sternberg, 1984, Developmental Review, 4, 113–138) should have been. I believe the article fulfills my own purpose, if not Yussen's.     

Smoking and academic performance

Smokers and nonsmokers were compared on three aspects of academic achievement. Although exactly the same percentage of smokers and nonsmokers passed the first-year university examination, smokers obtained significantly higher marks. Similarly, smokers achieved significantly higher marks in their final year examinations in comparison with nonsmokers. Finally, a comparison of the tutorial essay marks of the smokers and nonsmokers again showed that smokers obtained significantly higher marks than nonsmokers. These data are consistent with the idea that ambitious students adopt smoking in the belief that it will help them study and sustain concentration.     

Mechanisms of blocking by contextual stimuli

The influence of contextual stimuli on the conditioning and performance of responding to a discrete stimulus was examined in the US preexposure paradigm using both context shift manipulations and a measure of context conditioning. Four groups of rats received both repeated exposure to an electric shock US in one context (Context 1), and repeated nonshocked exposure to a second context (Context 2). Two additional groups of rats received exposure to these contexts, but never received shock presentations. Rats exposed to shock learned to escape from the stimuli of Context 1, but did not escape from the stimuli provided by Context 2. Rats not exposed to shock failed to escape from either context. All rats then received a single CER conditioning session in which four pairings of a 3-min noise CS and shock US were presented. Half the rats received those CS-US pairings in the excitatory Context 1, while the remaining rats received those pairings in the neutral Context 2. Finally, half the rats in each of the CER conditioning treatments received extinction test trials of the noise CS in Context 1, while the remaining rats received those test trials in Context 2. Thus, this design factorially manipulated the presence of excitatory or neutral contextual stimuli during both conditioning and testing of a discrete CS. In comparison with the two groups of rats never preexposed to shock alone, attenuation in acquisition of conditioned suppression observed during test trials occurred only when CER conditioning had been administered in the excitatory Context 1, and this effect was manifested when testing occurred in either the excitatory Context 1 or the neutral Context 2. These results support the model of R. A. Rescorla and A. R. Wagner (1972) (in A. H. Black & W. F. Prokasy (Eds.) Classical Conditioning II, pp. 64–99, New York: Appleton-Century-Crofts) which asserts that contextual stimuli and sicrete CSs compete for limited associative strength supportable by a given US.