Rodents' (Rattus, Mesocricetus, and Meriones) use of learned caloric information in diet selection

When given a choice between two mashes of equal caloric density but differing flavors, rats (Rattus norvegicus) show a robust preference for the flavor previously associated with a higher calorie food. This finding suggests that rats may identify food quality by sensory cues such as taste. Our initial attempt to show this effect in the golden Syrian hamster (Mesocricetus auratus) failed, apparently because of this species's tendency to store both high- and low-calorie mashes in their cheek pouches during conditioning trials. Initially we attempted to circumvent this seeming morphological constraint on learning by presenting low- and high-calorie mashes on alternate days. This procedure too failed to produce evidence of flavor-caloric learning, although this procedure produced robust learning in another rodent, the Mongolian gerbil (Meriones unguiculatus). Another method of preventing cheek pouching--concurrently presenting low- and high-calorie liquid diets--was more successful; then, hamsters showed clear evidence of flavor-caloric learning. Thus, although flavor-caloric learning is demonstrable in species of rodent besides the rat, the circumstances under which it occurs vary.     

Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): III. Contact calls

We trained budgerigars by operant conditioning to discriminate among a set of contact calls in a same-different task and analyzed response latencies from this task by using multidimensional-scaling (MDS) and cluster-analysis procedures. Humans listened to the same calls and indicated the similarity between pairs of calls by a direct rating procedure. An MDS program (sindscal) was used to arrange these complex acoustic stimuli in multidimensional space reflecting perceptual organization. Multiple regression techniques were used to identify the acoustic characteristics of contact calls that were correlated with the perceptual dimensions obtained from MDS. A number of spectral characteristics (e.g., peak frequency, rate of frequency modulation, and concentration of spectral energy) emerged as important for both budgerigars and humans, but the relative salience of these cues differed for the two species. Additional tests with two groups of budgerigars--cagemates and noncagemates--showed that experience with calls can change the salience of various acoustic characteristics used for perceptual organization and individual recognition.     

Learning from lectures: The effect of varying the detail in lecture handouts on note-taking and recall

Previous research on the effect of lecture handouts on student learning indicates that students who are given skeletal handouts usually perform better in course examinations than students who take all their own notes. The present study investigates whether the amount of detail in the handout is a critical factor in this. A randomized groups experiment was conducted in the context of a course on dental surgery. Four lecture handout conditions (headings and full text; headings and key points; headings only; no supplementary materials) were compared on tests 2 days and 2 weeks after the lecture. The significant differences between conditions were: ‘headings only’ better than ‘headings and key points’ on the first test; ‘headings only’ better than ‘no supplementary materials’ on the second test; and ‘headings and full text’ better than ‘no supplementary materials’ on the second test. These results indicate that the amount of detail is a critical factor in handout effectiveness.     

Computerized Career Information and Guidance Systems: Caveat Emptor

Computerized career information and guidance systems, although now commonplace, have received little psychometric scrutiny. The authors argue for examining these systems in the same way in which paper and pencil instruments are assessed. Consideration is also given to issues related to programming, technical-service problems, and staffing.     

Coping with the exposure to torture

This paper describes approaches taken at the International Rehabilitation and Research Centre in Copenhagen to helping torture victims and their families cope with the exposure to and aftermath of torture.     

Effect of social support on the stress-burnout relationship

Business organizations have become interested in recent years in the role of social support in reducing the negative effect of stress. The purpose of this research is to examine the effects of two types of social support (i.e., job and life support) on the relationships between job and life stress and burnout. Participants consisted of 270 males and 254 females. For both males and females job stress and life stress correlate positively with burnout, while job and life support were negatively correlated with burnout. The hypothesis that social support would moderate stress-burnout relationships was not supported. Neither job support nor life support moderated job stress or life stress-burnout relationships. Females exhibited significantly higher levels of burnout, job stress, and life stress than males; however, there was no difference between males and females in the amount of social support received.     

Applying cognitive theory to the testing and teaching of intelligence

This article describes how cognitive theory can be applied to the testing and teaching of intelligence. The article is divided into three main parts. The first part describes how the study of intelligence, traditionally an area that has been viewed as under the purview of differential psychology, has come squarely into the purview of cognitive psychology. The second part describes how the testing and teaching of intelligence, which in the past have been largely atheoretical, have been transformed into theoretically based enterprises guided by the theories of cognitive psychology. The last part describes a particular theory of intelligence, the triarchic theory, and how it has been applied to the problems of testing and teaching intelligence. It is concluded that cognitive psychology has given the study of intelligence a ‘new lease on life’, and that the testing and teaching of intelligence can and should be viewed as a primary focus of application for the principles of cognitive psychology.