A cross-sequential analysis of developmental differences in speed of visual information processing

Development of processing speed was examined in three backward masking studies. The first verified the central nature of backward masking for children aged 8 and 11 years and for adults. The second suggested that task requirements were equivalent for children similar to those in Study 1, and that age differences in performance were not attributable to nonprocessing variables. The main cross-sequential study estimated speed of processing in 80 children (approximately 6 years to 13 years) and young adults using an inspection time task. Target exposure duration was varied to establish the time required to achieve a high level of discriminative accuracy. Estimates of processing speed increased until about 11-13 years of age; beyond this, the trend was less obvious, and it is possible that inspection time asymptotes at around the onset of adolescence. Performance improvement after 1 year could not be explained as resulting from practice since improvement among controls over a period of 2 weeks was significantly less. Correlations between estimates of inspection time made up to 2 years apart found the measure to be reliable.     

Masculinity,femininity, self-esteem,and subclinical depression

A study involving 197 university undergraduates (83 males, 114 females) tested the hypothesis that depressive symptoms assessed by the short form of the Beck Depression Inventory (BDI) would be negatively related to masculinity (M) scores from the Personal Attributes Questionnaire (PAQ) but unrelated to femininity scores (F). It was also hypothesized that the negative relationship between masculinity and self-reports of depressive symptoms may be due to shared variance in self-esteem. The results supported predictions. In particular, the negative relationship linking masculinity to depressive symptoms disappeared when the effects of self-esteem were partialed out. Results are discussed in terms of the thesis that self-esteem may reflect in part the dominant masculine values of Western-type cultures and that manifestations of psychological ill health may occur when there is reduced opportunity to engage in behaviors that reflect these values.     

Gender roles,biological sex,and predisposition to conflict management

The Bem Sex-Role Inventory and the Communication-Conflict Instrument were administered to 182 husbands and wives. Results suggest that gender-role classification is a more significant discriminator of communication behavior than is biological sex. Androgynous spouses, more than feminine though not significantly more so than masculine spouses, reported themselves to be the most disposed to handle conflict constructively. On the subscales of the conflict instrument, androgynous persons had significantly more positive feelings scores than either masculine or feminine persons, plus higher task energy and desire-for-control scores than feminine persons. Similarly, masculine persons reported a significantly greater predisposition to manage conflict constructively than did feminine persons, having higher task energy and desire-for-control scores. Undifferentiated persons reported the lowest scores for conflict management.     

Selective cardiovascular effects of stress and cigarette smoking in young women

In an earlier study, we found that men who smoked a cigarette and then engaged in a mildly stressful activity (video game) evidenced pronounced increases in heart rate and blood pressure, which were approximately equal to the sum of the effects produced by either smoking alone or stress alone. In the present study, a 2 (smoke vs. sham smoke) X 2 (stress vs. no stress) factorial design was used to evaluate the impact of stress and smoking on the cardiovascular responses of young women. The results revealed that the combination of stress and cigarette smoking produced blood pressure and heart rate responses that were larger than the additive effects of smoking and stress taken separately.     

Co-occurrent use of cigarettes, alcohol, and coffee in healthy, community-living men and women

Previous studies have examined intra-individual aggregation in the use of cigarettes, alcohol, and coffee by examining the co-occurrent use of any pair of these three substances. A recent literature review failed to find a single investigation that studied use of all three in the same sample. In the present study, co-occurrent use of all three of these substances was examined in crossvalidated subsamples of 226 male and 245 female healthy, community-living, middle-class Americans. A log-linear analysis was used to compare the proportion of smokers, ex-smokers, and nonsmokers categorized as users of more or less amounts of coffee and alcohol. Although most of the intercorrelations were not strong, the results indicate that for both sexes, smokers and ex-smokers were more likely than nonsmokers to drink greater amounts of alcohol and coffee. Furthermore, for smokers, ex-smokers, and nonsmokers, a majority of individuals who reported drinking more alcohol also reported drinking more coffee. Interestingly, the coffee and alcohol consumption levels of ex-smokers resembled those of smokers more than those of nonsmokers. Also, ex-smokers reported drinking more wine and decaffeinated coffee than either smokers or nonsmokers. Finally, the number of cigarettes smoked per day (daily quantity) was positively related to total alcohol and coffee consumption in men, but not in women. Further studies are recommended to examine the role of individual differences in the development, maintenance, and modification of these three appetitive habits and their co-occurrence.     

Conditioned suppression of proboscis extension in Drosophila melanogaster

Food-deprived Drosophila melanogaster extend their proboscises following sucrose stimulation of the front tarsi (the proboscis extension reflex). Médioni and Vaysse (1975) reported that the inhibition of this response can be conditioned over trials if such proboscis extensions are punished by applying an aversive stimulus to the foreleg tarsi. In this study, Médioni and Vaysse's basic observations of conditioning were replicated, with a different strain of flies and a modified conditioning apparatus.     

Ventral scent marking in Meriones unguiculatus may contribute to thermoregulation

Three experiments were conducted with adult male Meriones unguiculatus in an attempt to demonstrate that ventral scent marking can act to transfer body heat to the object marked. Experiment 1 showed that surgical removal of the ventral gland pad reduced the amount of heat transferred by 50%, even though intact and glandless animals did not differ in the average frequency of scent marking. Experiment 2 demonstrated that the difference in heat transfer due to the presence or absence of the scent pad was not due to differential pressure applied to the substrate during marking. Experiment 3 showed that the pattern of ventral hair spread that occurs as an animal moves over an object is different between intact and glandless animals but that this difference does not account for the difference in heat transfer. It is suggested that heat transfer to the environment with ventral scent marking may increase thermoregulatory competence and also may function to volatilize sebum used in chemocommunication.     

Responsiveness to estrous chemostimuli in male rats (Rattus norvegicus) of different ages

Previous findings indicate that Norway rats (Rattus norvegicus) respond differentially to estrous chemostimuli in early infancy and that adult male sexual responsiveness to such chemostimuli depends on infantile experience with suckling odors (Fillion & Blass, in press). The development of behavioral responsiveness to estrous chemostimuli in male rats from late infancy to adulthood was examined in this study. Preweanling, adolescent, and adult males were observed for 20 min in the presence of an anesthetized estrous or an anesthetized diestrous female. This was, for adolescent and adult subjects, the first heterosexual encounter since weaning. Rats in each age-group responded differentially according to female state, but in distinct, age-related ways. Preweanling spent more time investigating the female's body if she was estrous. Adults expressed the same affinity but by more focused investigation directed perivaginally. Adolescents showed no female-directed bias but groomed themselves more if the female was estrous. These data identify developmental continuities and discontinuities in male rat behavior toward sexually receptive females.     

Borderline and psychotic adolescents' relationship to their parents: a therapeutic point of view

This study investigated the parents of 100 psychotic and borderline adolescents, and their relationships with their adolescent children. The incidence of psychiatric disorders among the parents, and the incidence of one-parent homes, as well as the divorce rate of biological parents, are given. A direct assessment of the number of pathological relationships between adolescents and parents, defined from a therapeutic point of view, was also made. Examples are given of parental pathology or marital discord concealed in the adolescents' pathology, or in the parent-adolescent relationship. It was concluded that the assessment of parents and their relationships with the adolescents is important for the treatment of the adolescent.