Individual differences in the reactivity of young infants.

Although reports of individual differences in reactivity have recently emerged in the literature, information is still lacking on the ontogeny and stability of this phenomenon over the first months of life. To address this issue, the responses of 40 newborns to PKU screening at 2 days of age were videorecorded. At 2 months, when the infants received their first DPT shot, their behavior in response to the inoculation was also videorecorded. Besides duration of crying, the intensity of fussing and grimacing was determined. Irrespective of birth characteristics, measures of reactivity were related over the first 2 months of extrauterine life. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Racial differences in stress-induced cardiovascular reactivity and hypertension: Current status and substantive issues.

Essential hypertension is perhaps the number-one health problem of Black Americans. Research has indicated that stress-induced cardiovascular hyperreactivity may be a significant contributor to essential hypertension. The high prevalence of hypertension among Blacks suggests that this group, in comparison with Whites, may be particularly susceptible to cardiovascular hyperreactivity. The first portion of this article reviews research to date that has examined racial differences in resting and stressor-induced cardiovascular activity. The second half of this article overviews some critical methodological and conceptual issues involved in the study of racial differences in reactivity. These issues include the effects of Black-White differences in plasma renin levels and sodium excretion, the effects of experimenter race, and differences in perceptions of the laboratory environment. Additionally, the issue of racial group classification and the implications this has for interpreting Black-White differences in reactivity is discussed. Two perspectives on racial group classification, the genetic and the sociocultural, are addressed in some detail, and the relevance of each to research on racial differences in stress reactivity is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race differences in brain size.

Comments on J. P. Rushton's (see record 1995-17150-001) reply to a critique of his work (e.g., see record 1993-40406-001) on biological differences among human racial groups. Rushton's categorization of racial brain weights cannot be valid because (1) comparisons of individuals drawn from the same sex and species do not allow for meaningful predictions of brain weight and (2) there is no justification for scaling brain size to body parameters. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race differences in brain size.

Replies to M. Peters's (see record 1996-14159-001) comments on Rushton's (see record 1995-17150-001) reply to a critique of his work (e.g., see record 1993-40406-001) on brain size differences among human racial groups (i.e., Mongoloids, Caucasoids, and Negroids). Rushton reports on 4 independent ways of estimating brain size, and confirms that brains of East Asians average about 17 cm–3 larger than those of Europeans, whose brains average about 80 cm–3 larger than those of Africans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences in basal protein kinetics in young adults

Gender affects energy expenditure and influences the relative utilization of carbohydrate and fat as fuels. However, little is known about the possible effects of gender on protein metabolism. Thus, we compared whole body and plasma (albumin and fibrinogen) protein kinetics in the basal postabsorptive state in young, untrained volunteers divided into two groups according to gender (women: n=17; age, 24+/-4 yr; men: n=17; age, 25+/-2 yr). The two groups were matched for body mass index. Protein kinetics were measured by means of L-[1-14C]leucine infusion. The leucine whole body rate of appearance, an index of proteolysis, and nonoxidative rate of disappearance, an index of protein synthesis, were similar in the two groups. However, the leucine oxidation rate was significantly lower in women compared to men (0.23+/-0.07 vs. 0.31+/-0.08 micromol/kg min; P=0.0062). Similar results were obtained when data were adjusted for estimated body composition. Albumin and fibrinogen fractional secretion rates were not different in the two groups. In conclusion, in the basal state leucine oxidation is lower in women than in men regardless of body composition. This could be one of the factors contributing to the lower metabolic rate in women.     

Back pain in young athletes. Significant differences from adults in causes and patterns

The ubiquitous occurrence of Legionellae requires an exact typing of isolated strains in order to demonstrate the source of infection. Monoclonal antibodies, analysis of genomic and plasmid DNAs, and the typing of alloenzymes are suitable for this purpose. Typing of Legionella pneumophila serogroup 1 strains by using monoclonal antibodies was found to be a rapid and adequate method. Other serogroups of L. pneumophila and non-pneumophila species are of considerably less antigenic diversity, so that the use of monoclonal antibodies is not particular profitable. In such cases, genotypic methods are needed to discriminate between unrelated strains. There are no changes in the genome structure, defined as restriction patterns, during passages on artificial media and cultured Acanthamoeba. The possibility that different species, serogroups and monoclonal or genomic subtypes can be isolated in a given water supply points to necessity to test a sufficiently large number of colonies grown from the water samples. A clonal distribution of some Legionella strains has been observed.     

Gender differences in alcohol and other drug use among young adults

This article describes gender differences in alcohol and other drug (AOD) use and misuse in a representative sample of young women and men in the United States. Data were drawn from the National Longitudinal Survey of Youth (NLSY) and focus on gender differences in prevalence and patterns of AOD use in African American, Hispanic, and White young adults ages 19 to 24 years old. Findings are summarized and implications for prevention are presented.     

Genes, environment and individual differences in alcohol expectancies among female adolescents and young adults.

Alcohol expectancies are an important proximal causal risk factor in several models of the familial transmission of alcohol use, abuse, and dependence, yet the familial transmission of alcohol expectancies is not well understood. The purpose of this study was to examine the familial transmission of positive alcohol expectancies. Participants were 2,627 14- to 22-year-old female twins. Experiences shared by twins, rather than genetic factors, explained most of the familial similarity for positive alcohol expectancies, but an even larger proportion of the variation in positive alcohol expectancies was explained by nonfamilial factors. The extent to which the familial similarity for positive alcohol expectancies was moderated by age, race, drinking status, and the sharing of peer groups was also examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory self-efficacy and performance differences in young and old adults: The effect of mnemonic training.

We evaluated the hypothesis that mnemonic training would result in higher memory self-efficacy and better memory performance in young and old adults. Forty-eight young adults (17- to 19-year-olds) and 45 old adults (60- to 78-year-olds) received either training in the method of loci or no training and were given either performance feedback or no feedback on a serial-word recall task. Ss were tested at pre- and posttraining and were asked to rate their self-efficacy strength (SEST) and self-efficacy level (SEL) at each test session. Young adults recalled more than old adults and had higher self-efficacy scores. Training with feedback improved recall performance in both age groups but failed to increase SEST or SEL. When SEL scores were used to derive a measure of prediction inaccuracy, no age differences were observed. We conclude that efficacy expectations and attributions for memory performance may influence mnemonic training outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Older adults prefer less choice than young adults.

Previous research has demonstrated that older adults prefer less autonomy and seek less information when making decisions on their own relative to young adults (for a review, see M. Mather, 2006). Would older adults also prefer fewer options from which to choose? The authors tested this hypothesis in the context of different decision domains. Participants completed a choice preferences survey in which they indicated their desired number of choices across 6 domains of health care and everyday decisions. The hypothesis was confirmed across all decision domains. The authors discuss implications from these results as they relate to theories of aging and health care policy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Measures of postural steadiness: differences between healthy young and elderly adults

Measures of postural steadiness are used to characterize the dynamics of the postural control system associated with maintaining balance during quiet standing. The objective of this study was to evaluate the relative sensitivity of center-of-pressure (COP)-based measures to changes in postural steadiness related to age. A variety of time and frequency domain measures of postural steadiness were compared between a group of twenty healthy young adults (21-35 years) and a group of twenty healthy elderly adults (66-70 years) under both eyes-open and eyes-closed conditions. The measures that identified differences between the eyes-open and eyes-closed conditions in the young adult group were different than those that identified differences between the eye conditions in the elderly adult group. Mean velocity of the COP was the only measure that identified age-related changes in both eye conditions, and differences between eye conditions in both groups. The results of this study will be useful to researchers and clinicians using COP-based measures to evaluate postural steadiness.     

Race and sex differences in the prediction of drug use.

Efforts to prevent adolescent substance abuse often direct prevention efforts at known correlates of substance use. The applicability to minority populations of risk factors uncovered for the general population has been questioned, and the development of different programs targeting the risk factors most salient for different groups has been recommended. Such differentiated programming requires a more precise understanding of ethnic differences in the predictors of substance use than is now available. This article assesses these differences using data from 981 Black and White male and female adolescents and latent variable structural equations techniques. No group differences were observed in the prediction of past year variety of drug use for 9 of the 12 risk factors examined. The predictive validity was higher for Whites than for Blacks for 3 risk factors. The prediction of frequency of use was weaker for Black women than for other groups. The low predictive validity observed for Black women is most likely due to the extremely low level of use among this group. The study concludes that the measures of risk factors predict substance use for all groups examined but that extremely rare behaviors are not well predicted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Gender differences in the sensitivity to posttraumatic stress disorder: An epidemiological study of urban young adults.

The authors examine the relationship between 2 separate but interrelated findings in the epidemiology of posttraumatic stress disorder (PTSD): women's greater PTSD risk following traumatic events and the sensitizing effects of a prior trauma on the PTSD response to a subsequent trauma. Data come from a representative sample of 1,698 young adults from a large U.S. city. Analysis was conducted on the subset exposed to traumatic events. Women's risk for PTSD following assaultive violence was higher than men's. When assaultive violence preceded a later nonassaultive trauma in women, there was an increased risk (relative risk = 4.9) for PTSD, which was not observed in men. The relative risk estimate in women was significantly higher than in men. These findings suggest that assaultive violence elicits women's PTSD response directly and by sensitizing them to the effects of subsequent traumatic events of lesser magnitude. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experiences of depression in normal young adults.

Investigated depression as a normal affect state that could have continuity with types of clinical depression. A 66-item Depressive Experiences Questionnaire (DEQ) was constructed to assess a wide range of experiences that, though not direct symptoms of depression, are frequently associated with it. The DEQ, the Wessman-Ricks Mood Scale, a version of the semantic differential, and the Death-Concern Questionnaire were administered to 500 female and 160 male college students. In another sample, 128 college students were given the DEQ and the Zung Self-Rating Depression Scale. Three highly stable factors emerged from the DEQ: Dependency, Self-Criticism, and Efficacy. These factors had significant differential correlations with other measures, which support the interpretation of the factors derived from the items. These data indicate the need to consider dependency and self-criticism as 2 primary dimensions of depression and the value of investigating the continuity between normal mood states and the clinical phenomena of depressions. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generativity and social motives in young adults.

Different forms of generativity in the writings of E. H. Erikson (1950/1963) and J. Kotre (1984) were related to agentic and communal motives in a sample of young adults (M?=?28 yrs old). For women, the power motive related to parenting, whereas the achievement motive was associated with forms of generative expression outside of the household. The opposite pattern of achievement and power motive relationships was found for men, although in a weaker form. The affiliation–intimacy motive, on the other hand, related both to women's parenting and societal concerns. Differences in expectations and opportunities for young men and women may account for these gender differences. The results for women support D. P. McAdams's (1988) suggestions that agency and communion are important for understanding generativity. In addition, the results provide evidence that people begin to grapple with generative issues as young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Short-term memory scanning in schizophrenic young adults.

Used the Sternberg item-recognition procedure to investigate the process of short-term memory scanning and recognition of common English words in 16 schizophrenics, 16 nonschizophrenic psychiatric patients, and 16 normals (college students). The S was required to respond as quickly and accurately as possible to whether a probe word matched the word or words shown a few seconds earlier. Results show that the 3 groups' response latencies increased at approximately equal rates as the memory set size increased, but the overall response latencies of both patient groups were profoundly slower than normals. All 3 groups revealed a significant serial position effect and a logarithmic reaction time function for the positive probe. No single model of the scanning strategy appears to fit straight-forwardly to the present data. It is concluded that the schizophrenics' short-term memory scanning was intact, and their slowness in response is, therefore, to be understood in terms of some dysfunction in their stimulus encoding, response selection, and/or response execution. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sustained-attention capacity in young and older adults.

The sustained-attention capacity of young (21–29 years) and older (65–78 years) adults was examined using a high-event rate digit-discrimination vigilance task presented at 3 levels of stimulus degradation. Increased stimulus degradation led to a reduction in the hit rate and to a greater decline in hit rate over blocks (increased vigilance decrement). Sensitivity (d') declined over blocks only at the highest level of stimulus degradation. Older adults had a lower hit rate and showed greater vigilance decrement than young adults, particularly when stimuli were highly degraded. However, both age groups showed the same pattern of stability in sensitivity when stimulus degradation was moderate, and sensitivity decrement over time when stimulus degradation was high. The results suggest that the process of sustained allocation of capacity—as reflected in temporal changes in sensitivity—operates similarly in young and older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Race differences, strategy training, and improper inference.

Criticizes B. Bridgeman and J. Buttram's (see record 1975-30982-001) article on the facilitative effects of verbal strategy training or race differences in nonverbal reasoning. It is argued that an experiment involving a Group * Training or No-training design does not logically permit conclusions concerning the genetic or nongenetic causes of the main effect of the group differences or their interaction with treatments; nor can such a design reflect on the culture-fairness of the measuring instrument. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intimacy and identity status in young adults.

Intimacy status in 48 men and 44 women (aged 21–35 yrs) was investigated in relation to ego-identity status in occupation, religion, politics, and sex role. All Ss were college educated, and most were employed in professional or skilled occupations. An intimacy status measure developed by J. L. Orlofsky et al (1973) was modified for use with adults and expanded by the addition of the merger status, describing relationships in which one partner dominated the other. There were no significant sex differences in intimacy or identity status; and as predicted by E. H. Erikson's (1963) theory, intimacy status was generally related to identity status. This relationship was not observed for occupational identity in either sex. It is suggested that Erikson's theory regarding the pattern of identity and intimacy resolutions may be extended from men to women, at least for the type of sample studied in the present investigation. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)