Experience-dependent changes in dendritic arbor and spine density in neocortex vary qualitatively with age and sex

Male and female Long-Evans hooded rats were placed in the complex environments for 3 months either at weaning (22 days), in young adulthood (120 days), or in senescence (24 months). The dendritic morphology of both the apical and basilar fields of layer III pyramidal cells was analyzed in both parietal and visual cortex. There were two novel results. First, although spine density was increased significantly with complex-housing in adulthood, it was decreased significantly by the same housing during development. Second, dendritic length was increased in both parietal and occipital cortex at all ages in males and was increased in adult females as well, but juvenile females showed no change in dendritic length in the occipital cortex and only a small effect on the apical field in parietal cortex. Thus, there are qualitative differences in the changes in spine density at different ages and the dendritic changes in response to complex versus isolated housing vary with sex, and in females, the changes vary with age as well. These results may explain some of the apparent inconsistencies in reports of spine and dendrite changes in the literature.     

The factorial structure of sleep dissatisfaction

Research into sleep problems has been dominated by a number of theoretical perspectives from each of which useful treatment applications have been derived. However, the rich diversity of problems that are subsumed under insomnia or sleep disturbance often remain unappreciated. This paper reports the results of a factor analysis performed on the combined items of two questionnaires designed to assess sleep disturbance. Six factors are described, two of which relate to cognitive aspects of sleep disturbance; two which map onto sleep onset and sleep maintenance problems; and two which are drawn from dissatisfaction with poor sleep. Correlations of factor scores with measures of neuroticism, worry and various sleep history variables provide a strong level of construct validity. The results are discussed in terms of their treatment implications.     

Developmental changes in free recall: The interaction of task structure and age

Free-recall learning and organization were measured for 3rd, 7th, and 11th graders under conditions which varied the type and amount of task structure. Task structure for the input or list-presentation phase was manipulated by using a random, constant, or alphabetic item sequence across trials. Task structure for the output or recall phase was manipulated by providing standard instructions or instructions which suggested the possible use of an alphabetic ordering scheme. Recall performance and organization showed an interaction between age and both manipulations of task structure. The 3rd graders required the maximal amount of task structure (alphabetic order with alphabetic instructions) to demonstrate recall facilitation relative to the completely unstructured control condition. The 7th graders showed recall facilitation for intermediate and high levels of task structure, and the 11th graders showed recall facilitation for low, intermediate, and high levels of task structure. The results are related to current hypotheses about developmental changes in recall performance and their relationship to changes in the systematic use of organizational strategies.     

The factorial structure of individual differences in visual perception

Although at first glance the way we perceive the world is similar for most individuals and resembles a veridical interpretation of the environment, the persistent individual differences found in many perceptual processes continue to inspire and confuse researchers. Despite numerous attempts to map out the reliable factors and correlates of individual variance in perception, the factorial structure of vision has remained elusive. The current article reviews recent developments in the study of individual differences in perception with a focus on work that has applied latent variable techniques for analysing performance across multiple visual paradigms. As this overview reveals, studies that have attempted to answer the question whether one general or several specific factors best describe vision tend to reject the monolithic view. Some general notes are also provided regarding pitfalls that should be taken into account when designing such research in the future.     

Evaluation of the factorial and metric equivalence of the Sexual Assertiveness Scale (SAS) by sex

Sexual assertiveness refers to the ability to initiate sexual activity, refuse unwanted sexual activity, and use contraceptive methods to avoid sexually transmitted diseases, developing healthy sexual behaviors. The Sexual Assertiveness Scale (SAS) assesses these three dimensions. The purpose of this study is to evaluate, using structural equation modeling and differential item functioning, the equivalence of the scale between men and women. Standard scores are also provided. A total of 4,034 participants from 21 Spanish provinces took part in the study. Quota sampling method was used. Results indicate a strict equivalent dimensionality of the Sexual Assertiveness Scale across sexes. One item was flagged by differential item functioning, although it does not affect the scale. Therefore, there is no significant bias in the scale when comparing across sexes. Standard scores show similar Initiation assertiveness scores for men and women, and higher scores on Refusal and Sexually Transmitted Disease Prevention for women. This scale can be used on men and women with sufficient psychometric guarantees.     

Stereotyping of sex role in preschoolers in relation to age,family structure,and parental sexism

Forty-eight boys and 48 girls aged between 32 and 64 months were tested for stereotyping of sex role using a toy-preference technique. Scores for overt and covert measures of sexism and awareness of the dimension of sex-role stereotyping were also obtained from both parents of each child, as well as information on the target child's siblings. Analysis indicated the developmental nature of stereotyping of sex role in both boys and girls and the surprising finding that older siblings are much more important in the development of such stereotyping than are sexist parents. The influence of the child upon parental attitudes is also apparent. These findings and their interrelationships are discussed, suggesting new directions for research.The author wishes to thank Ann Barry, Director of the Glen Kindergarten, for her assistance in developing the materials used here and her extensive testing of the children included in this study. My thanks are also due to Professor D. J. Drinkwater and Drs. R. Boyd, S. Phillips, and J. Sweller for their assistance in grading the stereotyped toy illustrations used in testing the children.     

Sex and cultural differences in the factorial structure of the self-directed search

Holland's Self-Directed Search was administered to 247 male and 252 female high school students, aged 16 to 18 years, attending state schools in New Zealand. Principal factor analysis was used in an attempt to identify six orthogonal factors analogous to Holland's six personality types. The Social and Enterprising scales could not be split into two factors in either sample, and the Investigative and Realistic scales defined a single factor for the female students. Computed distances between pairs of the six personality types in five dimensional factorial space were compared with the relative ordering of the distances expected from Holland's hexagonal model. The positions of the types in space corresponded more closely with the model for the males than they did for the females. The results, in conjunction with those of similar studies in Israel and the United States, imply that the correspondence between some summary codes on the SDS and existing occupational classifications based on Holland's types may be less than perfect, particularly for females. Also, care should be taken when using codes on the SDS to calculate Holland's indices of “consistency,” especially for females.     

Preschoolers' beliefs about sex and age differences in emotionality

The goal of the present study was to assess preschoolers' beliefs about the frequency and intensity with which boys, girls, women, and men experience anger, sadness, and happiness. Sixty-seven middle-class preschool children (35 girls, 32 boys) were presented with drawings of adult and child figures of each sex, and were asked to rate how frequently and intensely the emotions were felt (91% of the children were white; the remainder were primarily black). Children's gender stereotyped beliefs were particularly strong for sadness and appeared to be based on a deficit-experience model for males. Sex of target differences also were found for children's beliefs about anger (favoring males). However, the sex difference in anger was based more on the degree to which anger is believed to be experienced rather than on differences in beliefs regarding males' and females' capacity to experience anger. Age of target differences were also found for sadness and anger, but not for happiness. It was concluded that preschoolers' beliefs about differences in emotions are complex, and vary as a function of the sex and age of the target person, and as a function of the specific emotion.Partial support for Richard Fabes was provided by a grant from the National Science Foundation (BNS-8807784). Partial support for Carol Martin was provided by a Women's Studies Research Award (CM1-1001) and a Faculty Grant in Aid (RWR-B658) from Arizona State University. The authors would like to thank Anita Petitti, Dennis Barrett, Amy Vogelson, Melinda Deacon, Kris Hughes, Amy Secklin, Hilary Rose, Melanie Smith, and Melinda Smith for their assistance with data collection and stimulus preparation. Thanks also goes to the teachers, staff, and children at the Arizona State University Child Laboratory Programs.     

Risk and protective factors in adolescents' drug use, and differences by age and sex

Adolescents' drug use has huge social and personal implications, so it is essential to identify risk and protective factors. In this research, the CTCYS was used with 2440 adolescents to detect risk and protective factors for drug use in the community, family, school and peers/individual; differences in risk and protective factors by age and sex; and relationships between risk and protective factors and substance use. Protective factors are high. Risk factors are high in the community, the school and the individual. Older adolescents have more risks and less protection than the youngest; and there are sex differences, because males have less protection and more risks. The risk factors more closely related to drug use are availability of drugs in the community, family attitudes favourable to drug use, family history of antisocial behaviour, early start and use of drugs by friends, perceived risk and attitudes favourable to drug use. In the protective factors, the role played by social skills for alcohol use is important.     

Pupil dilation, sex of stimulus, and age and sex of observer

10-yr.-old, 16-yr.-old, and 20-yr.-old male and female observers (ns = 10; N = 60) rated a number of male and female faces for how 'good-looking' they were. Some of these faces were identical save that in one version the pupils were larger. Pupil dilation in the photographs of males produced no significant effects, whereas pupil dilation in the female photographs caused such faces to be rated as more good-looking by the two oldest groups of male observers. The 10-yr.-old boys and the 16- and 20-yr.-old women rated the female faces with enlarged pupils as significantly less 'good-looking' than the same faces with smaller pupils.     

A semi-analytical method of factorial rotation to simple structure

A factorial rotational method is presented which represents a compromise between the use of subjective judgment characteristic of graphical methods and the routine application of analytical methods. At present the analytical methods seem to be inadequate for the discovery of a simple structure, while graphical methods require more subjective judgment. The method herein presented locates the axes for subgroups of tests by an analytical method. The judgments used in the selection of subgroups are based on graphic data concerning interrelation of the factors.     

Cross-sectional age differences and longitudinal age changes of personality in middle adulthood and old age

The present study examines different aspects of personality continuity (or change) in middle adulthood and old age both cross-sectionally and longitudinally. The sample comprised 445 middle-aged (42-46 years) and 420 older (60-64 years) participants, reassessed after a 4-year interval. Personality was measured using the NEO-FFI personality inventory. After having established strict factorial invariance, factor covariances were found to be equal for both age groups and at both testing occasions, indicating perfect structural continuity of personality. A number of age differences in personality emerged at both measurement occasions. Longitudinally, in both age groups, an average decline in Neuroticism was observed. Longitudinal stability coefficients were around .80 in middle-aged and old participants, implying high, but not perfect, differential continuity. With respect to continuity of divergence, statistically significant cross-sectional age differences were found for the variance of Openness at both measurement occasions. Eventually, concerning specific versus general continuity, a variety of medium effect-sized correlated changes in the Big Five personality domains across the 4-year period was established, implying that personality changes share a certain amount of commonality.     

Comment on factorial structure of the Kuwait University Anxiety Scale

The Kuwait University Anxiety Scale was administered to 138 American college students and three meaningful factors identified, somewhat different from those identified by Abdel-Khalek in 2000.