A methodological study of auditory lateralization

The just-noticeable-shift (JNS) threshold of a centered image was determined for four naive Ss A two interval forced choice situation was used under the method of constant stimuli. The three manners of presentation of the intensity imbalance were as follows: (1) an increase in intensity at one ear, (2) a decrease in intensity at one ear, (3) an increase in intensity at one ear produced concommitantly with a decrease in intensity at the opposite ear. The sign test demonstrated significant differences between method (2) and methods (1) and (3).     

Comparisons of some learning models for response bias in signal detection

The effects of variations in signal probability and varying degrees of correct feedback on response bias were studied in a yes-no auditory signal detection task. The main finding was that the bias towards saying yes was an increasing function of the frequency of signal feedback events, but did not depend on the correctness of the feedback. Several learning models coupled with a simple psychophysical and decision model yielded predictions about overall biases and certain sequential statistics. Only one model, which can be decribed as an “informational” model, gave a good account of both observed overall biases and sequential statistics. This model assumes the observer’s response bias is strengthened for the feedback-reinforced response when the observer’s sensory information is ambiguous or is contradicted by the feedback information.     

Gender vs. power: Self-posed behavior revisited

In an extended replication of Mills' (1984) study, equal numbers of male and female students in arts and science schools were photographed by a female undergraduate. Arts students, both male and female, displayed stereotypically female nonverbal behavior, i.e., smiling and head canting, but male undergraduates also canted their heads more than female undergraduates. Results were explained in terms of the meaning of these gestures and the arts/science effect interpreted as indicative of the greater power/esteem of the sciences. The findings also address wider issues of the meanings of non-verbal behavior.     

Is valentine still doubtful? A workshop model for children of divorce

We present this eight-session structured workshop format aimed at school-aged children of divorce who are considered psychologically healthy by family and teachers, in which we review the situations most frequently encountered by these families.In the workshop we offer an understanding vision of divorce while providing the children with the experience of working with therapists who are able to deal with highly troublesome issues in a caring atmosphere.Acknowledgements are expressed to Bernardita Cruz, school counselor, and Ilana Meler and Patricia Tahl, child psychologists.     

Harmonic accents in inference of metrical structure and perception of rhythm patterns

Research on rhythmic structure is somewhat fragmented, due in part to differential use ofterminology and a lack of research on the timing of harmonic accents. In this study, a harmonic and a temporal accent were pitted against each other in such a way as to form different rhythm patterns. In addition, two harmonic conditions that varied in the frequency of chord presentations (i.e., the composite rhythm) but not in the frequency of chord changes (i.e., the harmonic rhythm) were presented. Musicians and nonmusicians were requested to report perceived rhythm patterns inan attempt to determine the relative salience of the harmonic and temporal accents. In addition, a behavioral measure of the perceivedmeter was taken. Results indicated that the location of chord changes was the main determinant of subjects’ rhythmic perceptions and the perceived onset of a measure. Furthermore, although subjects primarily inferred different meters based on the composite rhythm, an interaction of metrical and rhythmic choices was found, indicating that perception ofrhythm patterns and inference of metrical structure may notalways be independent.     

Defining features of natural kinds and artifacts

Two experiments investigated the role of three types of features (physical characteristics, functions, and chromosomal/molecular structure) in determining membership in natural kind and artifact categories. In the first, subjects decided if an object X would still be an X if it were different in one type of feature. A significant interaction was found between word type and change type, with the effects of chromosomal/molecular changes significantly greater for natural kinds than for artifacts, and the effects of functional changes significantly greater for artifacts than natural kinds. In the second experiment, subjects judged whether something would be an X if it were unlike instances of X in two of the above types of features, but like instances of X in one. There was again a significant interaction, with the effects of chromosomal/molecular features significantly greater for natural kinds than for artifacts, and the effects of functional changes significantly greater for artifacts than for natural kinds. These results suggest that chromosomal/molecular features define membership in natural kind categories and functional features define membership in artifact categories. The implications of these findings for the meaning of defining features are also discussed.The first experiment was conducted by the first author as part of a senior comprehensive exercise at Carleton College. We thank Kathleen Galotti, Matthew Gish, Neil Lutsky, and an anonymous reviewer for comments on earlier drafts of this article.     

Race differences and the Spearman hypothesis

Certain published data have been reviewed and new data presented relevant to the so-called Spearman hypothesis concerning the racial differences on cognitive tests of black and white Americans. In the published data, the correlation between the profiles of low socio-economic and high socio-economic status (SES) whites became ?.90 when sex, area of the country, and grade/age were controlled. This nearly mirror-image relationship suggests that the residual across-the-board difference between the two groups is primarily on the general factor in intelligence. In contrast, the same correlation between blacks and the low SES whites was only ?.19. This indicated not only independence of the profiles but the presence of multiple causes of differences in addition to a possible contribution of the general factor. These published interpretations have now been confirmed by obtaining correlations between general factor loadings and the group differences for most of the same tests. For the SES dochotomy in whites this correlation is .86. For blacks and the low SES whites it is .17. When the two distributions of differences are correlated, a value of .42 is obtained. The Spearman hypothesis appears to apply primarily to differences in socio-economic status rather than race. Furthermore, one cannot assume a large genetic component for each set of differences. Nor can one argue that the possibility of a large environmental component for each set indicates common environmental causes.     

Is EEG α a consistent measure of individual differences?

Integrated EEG activity in the 9–13 Hz band was recorded from 24 Ss under three experimental conditions (Relaxation, Attentive Listening and Mental Arithmetic) in two separate sessions. Analysis of components of variance due to persons and the interactions of persons with sessions and with conditions pointed to the importance of the persons × conditions interaction. It is concluded that under typically employed conditions of testing EEG α is not a consistent measure of individual differences.