Internet use in the contemporary media environment

Although a significant amount of research has focused on traditional media choice and use, and even on some ‘new’ media, these studies have either neglected the Internet and World Wide Web or were conducted prior to their recent popularity. This study offers a novel exploration of individuals' use of three Internet functions (information retrieval, information giving, and conversation capabilities) in the context of the use of other communication media. Data from 684 individuals demonstrate that the Internet is a multidimensional technology used in a manner similar to other, more traditional media. Specifically, conversation features of the Internet align with mediated interpersonal technologies (the telephone and electronic mail), whereas the Internet's information‐retrieval and information‐giving features are used in ways similar to mass media channels (newspapers, television, and books and magazines). In addition, needs fulfilled by these channels cluster in ways consistent with past research, regardless of the technologies employed to meet them.     

In Vivo Hippocampal Acetylcholine Release During Exposure to Acute Stress

Hippocampal extracellular acetylcholine (ACh) and choline levels were evaluated using in vivo microdialysis in male Fischer 344 rats before, during, and following an 80-min exposure to two different stress conditions. Measurements were taken in rats restrained and immersed in a water bath containing either 37 degreesC (normothermic-restraint) or 20 degreesC (cold-restraint) water. Results were compared to normothermic-freely-moving rats. Cold-restrained rats displayed decreased ACh levels during cold exposure relative to both normothermic-restrained and normothermic-freely-moving rats. By the end of the cold exposure period and following removal from cold, ACh levels had returned to near-baseline values. Normothermic-restrained rats had levels similar to those of normothermic-freely-moving rats, except for a marked increase in ACh following removal from restraint. Cold-restrained rats displayed a gradual elevation in choline levels during cold stress, followed by a gradual decline after stress termination, whereas both normothermic-restrained and normothermic-freely-moving rats displayed gradual decreases during the microdialysis session. These findings demonstrate that central cholinergic neurotransmission can be altered by the application of, and removal from, acute stressors. In addition, the results suggest a possible relationship between the magnitudes of both the stressor and its cholinergic consequences.     

Clamped Corticosterone (B) Reveals the Effect of Endogenous B on Both Facilitated Responsivity to Acute Restraint and Metabolic Responses to Chronic Stress

To determine the effects of both corticosterone (B) and chronic stressors on acute ACTH responses to restraint, young male rats were exposed to streptozotocin-induced diabetes, cold (5-7 degreesC) or intracerebroventricular (icv) neuropeptide Y (NPY) for 5 d and then exposed to restraint within 2 h after lights on. Two groups of rats were studied: intact and adrenalectomized replaced with B pellets that maintained plasma B in the normal mean 24-h range of intact rats. In addition to ACTH and B responses to restraint on d 5, body weight, food intake, fat depots, glucose and other hormones were measured to determine the role of stress-induced elevations in B on energy balance. ACTH responses to restraint were normal in intact rats subjected to diabetes or cold. By contrast, there was no ACTH or B response to restraint in NPY-infused intact rats. All 3 groups of chronically stimulated adrenalectomized rats with clamped B had facilitated ACTH responses to restraint compared to their treatment controls. Overall food intake increased in all groups of stressed rats; however, augmented intake occurred only during the light in intact rats and equally in the light and dark in B-clamped rats. White adipose depot weights were decreased by both diabetes and cold and increased by NPY in intact rats; the decreases with cold and increases with NPY were both blunted and changes in fat stores were not significant in adrenalectomized, B-clamped rats. We conclude that: 1. diabetes- and cold-induced facilitation of restraint-induced afferent input to hypothalamic control of the hypothalamo-pituitary-adrenal (HPA) axis is opposed in intact rats by the elevated feedback signal of B secretion; 2. NPY does not induce facilitation of afferent stress pathways; 3. chronic stimulation of the HPA axis induces acute hyperresponsiveness of hypothalamic neurons to restraint provided that the afferent input of this acute stimulus is not prevented by B feedback; 4. stimulus-induced elevations in B secretion result in day-time feeding; 5. insensitivity of both caloric efficiency and white fat stores to chronic stress in adrenalectomized, B-clamped rats results from loss of normally variable B levels.     

Intercultural Study of Personal Space: A Case Study

The study of intercultural differences in personal space attempts to identify factors that could be helpful in guiding people from different cultures to live and work together in international ventures. The objective of this research was to measure interpersonal distance in a cross-cultural environment. Twenty-three participants classified in 4 cultural groups answered an 11-questions interview where the personal distance and orientation between seated interactants were measured. Results showed that Anglo Saxons used the largest zone of personal space, followed by Asians, then Caucasians, and, as expected, Mediterraneans and Latinos used the shortest distance. Where Latinos adopt a face-to-face position, Caucasians tend to orient themselves to the side of the interviewer, which has an impact on interpersonal communication.     

Testosterone–status mismatch lowers collective efficacy in groups: Evidence from a slope-as-predictor multilevel structural equation model

The study of the biological underpinnings of behavior is in its nascent stages in the field of management. We study how the hormone testosterone (T) is related to status and collective efficacy in a group. We assessed salivary testosterone of 579 individuals in 92 teams. We find that T does not predict status within the group. We also tested the effects of a mismatch between T and status in the group on the collective efficacy of the group. Using a novel slope-as-predictor multilevel structural equation model, we find that the greater the mismatch between T and status in the group (i.e., the more negative the within-group correlation among T and status), the lower is the collective efficacy of the group. We discuss the implications of our findings for the study of the biological underpinnings of group behavior in organizations.     

Job performance over time is a function of latent trajectories and previous performance

Previous literature addressing job performance over time notes that past performance can affect future performance and that individuals often have distinct latent performance trajectories. However, no research to date has modeled these 2 aspects of job performance in tandem. Drawing on previous literature, the authors note that current performance may act as performance feedback, influencing future performance directly (i.e., autoregression), and that individuals differ in their performance trajectories due to individual-difference factors (i.e., latent trajectories). The authors demonstrate an autoregressive latent trajectory (ALT) model to show how both autoregressive and latent trajectory parameters may be incorporated in modeling job performance over time. Also discussed are the implications of the ALT model for future studies examining job performance longitudinally.     

The genetic basis of entrepreneurship: Effects of gender and personality

Extending previous research on the genetic underpinnings of entrepreneurship, we investigate gender differences in the genetic influences on the tendency of people to become entrepreneurs. We also examined two mediating variables through which genetic factors may impact this tendency: extraversion and neuroticism. Based on 1285 pairs of identical twins (449 male and 836 female pairs) and 849 pairs of same-sex fraternal twins (283 male and 566 female pairs), we found that females have a strong genetic influence and zero shared-environmental influences on their tendency to become entrepreneurs. In contrast, males show zero genetic influence, but a large shared-environmental influence. Extraversion and neuroticism mediate the genetic influences on women’s tendency to become entrepreneurs, whereas extraversion mediates shared-environmental influences on men’s tendency to become entrepreneurs. We discuss this sharp difference in genetic influences on entrepreneurship across gender groups and highlight the different challenges that men and women face in their entrepreneurial endeavors.     

The genetics of economic risk preferences

We examine the influence of genetics on economic risk preferences by administering a measure of these preferences to monozygotic (MZ) (i.e., identical) and dizygotic (DZ) (i.e., non‐identical) twin pairs. Our analysis supports a dominant genetic effect and virtually no additive genetic effect on economic risk preferences, with the heritability of preferences estimated at 0.63. These findings suggest that over half of the variation in such preferences can be explained by genetic factors, with the remainder of the variance explained by environmental influences not shared among sibling twins. We discuss the implications of our findings for the study of individual differences in economic risk preferences. Copyright © 2009 John Wiley & Sons, Ltd.     

Testing 1, 2, 3, …4? The personality of repeat SAT test takers and their testing outcomes

The current study considered the correlates of test retaking. In particular, the personality trait of neuroticism was proposed to be related to retaking the SAT test. Results revealed that, accounting for initial SAT score and the other Big Five factors of personality, neuroticism predicted the number of times an individual took the SAT before attending college. Further, the results of a latent growth model indicated that, for those who retook the SAT, test scores showed improvement over time. None of the Big Five predicted changes in SAT scores. Results are discussed in light of the possible benefits of high levels of neuroticism for SAT score improvement.