Robert J. Pellegrini

Handedness and birth risk.

Abstract Based in part on a relationship he observed between the incidence of left-handedness and birth risk (defined by birth order) in male college students, Bakan has postulated that left-handedness is the result of neurological insult associated with pre-natal or delivery factors. The two replications which question Bakans hypothesis can be criticized as replications for suspected differences in each sample and because both failed to consider sex as a variable. When these variables were taken into account, no evidence of a relationship between left-handedness and birth risk was observed for male or female college students.

STRIKING CHANGES IN THE SLEEP SATISFACTION OF UNIVERSITY STUDENTS OVER THE LAST TWO DECADES

Over two decades, our data document a substantial linear increase in the percentage of university students who self-reported dissatisfaction with their sleep, i.e., 24% in 1978, 53% in 1988, and 71% in 2000.

Handedness and Anxiety

The anxiety scores of 23 left-handed, 12 mixed-handed and 35 right-handed college students were compared with the result that right-handers were significantly less anxious then both the left and the mixed-handed groups (which did not differ statistically). Since these data appear to be unique, generalizations from them was thought to be premature.

Correlation between handedness and birth order: compilation of five studies.

Bakan has suggested that left-handedness is the result of left hemispheric pyramidal motor dysfunction following perinatal hypoxia. To a degree support for the validity of this hypothesis rests on Bakans (1971, 1977a) findings that left-handed college students were more likely the progeny of birth orders designated as “high-risk” than right-handed students. Attempts by others to replicate Bakans data have been unsuccessful. To achieve a more powerful test of this relationship than has been provided by any single study, the data from the five studies which have considered it were pooled and tested. The resulting correlation between birth order and handedness was near zero.

Political Identification and Perceptions of Homelessness: Attributed Causality and Attitudes on Public Policy:

The study investigated relationships between political orientation, causal perceptions of poverty, and attitudes toward government programs for the poor. The test sample of 200 women and 200 men were recruited from introductory psychology classes. In support of hypotheses based on previous research and Weiners attribution-emotion-action theory, when compared with self-identified Democrats, self-identified Republicans (a) were significantly more inclined to attribute homelessness to internal vs external factors and (b) expressed significantly less favorable attitudes toward publically funded programs for the homeless. Sex differences were nonsignificant. Conceptual-empirical and methodological implications are discussed. Limitations on inferences from these data and directions for inquiry into the development of individual differences in political cognitions and public policy attitudes are considered.

The Astrological “Theory” of Personality: An Unbiased Test by a Biased Observer

Summary The astrological assumption of personality differences among individuals born under different sun signs was investigated. Significant differences were obtained between sun sign groups on four of the 18 scales of the California Psychological Inventory (CPI) as follows: Communality, Socialization, Flexibility, and Femininity. The overall pattern of results based on F ratios, multiple comparisons between means, and estimates of strength of association was interpreted as showing no meaningful relationships between sun sign and scores on Communality, Socialization, and Flexibility. Adopting even the most conservative standards of inference, however, all of the test statistics employed indicated a powerful effect on the Femininity scale. Implications for future research were discussed.

Birth Complications and the Distribution of Handedness

In an attempt to clarify the relationship between self-reported birth complications and handedness, the handedness distributions of 181 college students who reported birth complications and 1320 students who reported no complications were compared. The results suggest a clear but modest shift in the birth complications group away from the dextral end of the continuum. However these data did not validate the hypothesis that left-handedness results from birth complications.

Type A behavior and normal habitual sleep duration

The responses of 361 college students to the Jenkins Activity Survey and a self-report sleep questionnaire were used to demonstrate an inverse relationship between normal habitual sleep duration and level of Type A behavior. The possibility that patterns of sleep may be implicated in the development of Type A behavior in some individuals was considered.

Handedness and sleep duration.

The differences in habitual sleep duration and absolute deviations in habitual sleep duration from the normative mean between 60 left-, 36 mixed- and 125 right-handed college students were tested. It was found that mixed-handers tend to sleep less and as a group show significantly greater deviations in habitual sleep durations than either left- or right-handers. The heuristic value of this relationship for future research was discussed briefly.

A unidimensional short form of the TMAS

The results of four factor-analytic studies have demonstrated that items of the TMAS load into several uncorrelated factors. To partially resolve the issue raised by these data, for the validity of the TMAS, a unidimensional short form of the TMAS was constructed.