Development of upper limb proprioceptive accuracy in children and adolescents

This study was designed to determine differences in the proprioceptively guided movements of children (8-10 years) and adolescents (16-18 years). Participants were blindfolded and asked to actively match passively determined target positions of the elbow joint under three matching conditions. Overall, children were less accurate than adolescents in all matching tasks and utilized different kinematic strategies for making the matching movements. Specifically, children made larger absolute errors and utilized matching movements which, compared to adolescents, were of shorter duration and less irregular in terms of their velocity profiles. An assessment of limb asymmetry was also performed revealing a non-dominant arm matching advantage but only for children and only in the task requiring interhemispheric transfer of a memory-based model of limb position. The proprioceptive differences observed in this study are likely the result of experience-driven refinement in the utilization of somatosensory feedback throughout childhood and into adolescence.     

Emotional and deliberative reactions to a public crisis: Mad Cow disease in France

Although most theories of choice are cognitive, recent research has emphasized the role of emotions. We used a novel context--the Mad Cow crisis in France--to investigate how emotions alter choice even when consequences are held constant. A field study showed that individuals reduced beef consumption in months after many newspaper articles featured the emotional label "Mad Cow," but beef consumption was unaffected after articles featured scientific labels for the same disease. The reverse pattern held for the disease-related actions of a government bureaucracy. A lab study showed that the Mad Cow label induces people to make choices based solely on emotional reactions, whereas scientific labels induce people to consider their own probability judgments. Although the Mad Cow label produces less rational behavior than scientific labels, it is two to four times more common in the environment.     

Serial recall and presentation schedule: a micro-analysis of local distinctiveness

According to temporal distinctiveness theories, items that are temporally isolated from their neighbours during presentation are more distinct and thus are recalled better. Event-based theories, which deny that elapsed time plays a role at encoding, explain isolation effects by assuming that temporal isolation provides extra time for rehearsal or consolidation of encoding. The two classes of theories can be differentiated by examining the symmetry of isolation effects: Event-based accounts predict that performance should be affected only by pauses following item presentation (because they allow time for rehearsal or consolidation), whereas distinctiveness predicts that items should also benefit from preceding pauses. The first experiment manipulated inter-item intervals and showed an effect of intervals following but not preceding presentation, in line with event-based accounts. The second experiment showed that the effect of following interval was abolished by articulatory suppression. The data are consistent with event-based theories but can be handled by time-based distinctiveness models if they allow for additional encoding during inter-item pauses.     

Sexual victimization in relation to perceptions of risk: mediation, generalization, and temporal stability

There is evidence that personal experience with trauma is associated with increases in both personal and comparative risk perception. This study investigates this relation in terms of sexual victimization among women, focusing on three potential mediators: perceived control over sexual assault, perceived similarity to a typical sexual assault victim, and psychological distress. Mediational analyses were investigated using structural equation modeling. Although victimization experience was not related to comparative risk perception, it was associated with greater personal risk perception. This relation was mediated by perceived similarity to a typical sexual assault victim. Prospective analyses indicated that personal risk perception does change in response to sexual victimization but also indicated that heightened risk perception may be an accurate assessment of risk that actually precedes victimization experience. Implications for the meaning of perceived similarity and perceptions of risk for sexual assault victims are discussed.     

Dying to be thin: the effects of mortality salience and body mass index on restricted eating among women

Following terror management theory, the authors suggest women's striving to attain a thin physique is fueled in part by existential concerns. In three studies, women restricted consumption of a nutritious but fattening food in response to reminders of mortality (mortality salience; MS). When conducted in private (Study 1), this effect was found among women but not men; when replicated in a group setting in which social comparison was likely (Studies 2 and 3), only women who were relatively less successful attaining the thin ideal (i.e., high body mass index; BMI) restricted eating after MS. In Study 3, MS caused high BMI women to perceive themselves as more discrepant from their ideal thinness; this perceived failure mediated the effects of MS and BMI on eating behavior. Findings are discussed from a self-regulatory framework, which considered in the context of pressures for women to be thin, can shed light on health risk behavior.     

Assessing aggression in adolescent romantic relationships: can we do it better?

Almost all research on aggression in adolescent romantic relationships makes use of 1-time, retrospective assessment methods. In the present research, the authors compared data on the experience of adolescent relationship aggression (physical aggression and threatening behavior) collected from 125 high school students via 2 methods: (a) a 1-time, 2-month retrospective assessment and (b) a cumulative method based on four 2-week retrospective assessments, each spaced 2 weeks apart. For the cumulative method, data from the 4 assessments were aggregated to cover the same time period as the single, 2-month retrospective assessment. A greater proportion of the sample (48.0%) reported experiencing physical aggression using the cumulative method compared with the single, 2-month retrospective method (27.0%). The prevalence of threatening behavior was also higher using the cumulative method (48.8% vs. 24.8%). Adolescent trauma and anxiety symptoms correlated more strongly with physical aggression data derived from the cumulative method than from the 1-time assessment method.     

Cross-cultural similarities and differences in North Americans’ geographic location judgments

We examined some potential causes of bias in geographic location estimates by comparing location estimates of North American cities made by Canadian, U.S., and Mexican university students. All three groups placed most Mexican cities near the equator, which implies that all e influenced by shared beliefs about the locationthree groups wers of geographical regions relative to global reference points. However, the groups divided North America into different regions and differed in the relative accuracy of the estimates within them, which implies that there was an influence of culture-specific knowledge. The data support a category-based system of plausible reasoning, in which biases in judgments are multiply determined, and underscore the utility of the estimation paradigm as a tool in cross-cultural cognitive research.     

Internet accessibility and usage among urban adolescents in Southern California: implications for web-based health research.

The World Wide Web (WWW) poses a distinct capability to offer interventions tailored to the individual's characteristics. To fine tune the tailoring process, studies are needed to explore how Internet accessibility and usage are related to demographic, psychosocial, behavioral, and other health related characteristics. This study was based on a cross-sectional survey conducted on 2373 7th grade students of various ethnic groups in Southern California. Measures of Internet use included Internet use at school or at home, Email use, chat-room use, and Internet favoring. Logistic regressions were conducted to assess the associations between Internet uses with selected demographic, psychosocial, behavioral variables and self-reported health statuses. The proportion of students who could access the Internet at school or home was 90% and 40%, separately. Nearly all (99%) of the respondents could access the Internet either at school or at home. Higher SES and Asian ethnicity were associated with higher internet use. Among those who could access the Internet and after adjusting for the selected demographic and psychosocial variables, depression was positively related with chat-room use and using the Internet longer than 1 hour per day at home, and hostility was positively related with Internet favoring (All ORs = 1.2 for +1 STD, p < 0.05). Less parental monitoring and more unsupervised time were positively related to email use, chat-room use, and at home Internet use (ORs for +1 STD ranged from 1.2 to 2.0, all p < 0.05), but not related to at school Internet use. Substance use was positively related to email use, chat-room use, and at home Internet use (OR for "used" vs. "not used" ranged from 1.2 to 4.0, p < 0.05). Self-reported health problems were associated with higher levels of Internet use at home but lower levels of Internet use at school. More physical activity was related to more email use (OR = 1.3 for +1 STD), chat room use (OR = 1.2 for +1 STD), and at school ever Internet use (OR = 1.2 for +1 STD, all p < 0.05). Body mass index was not related to any of the Internet use-related measures. In this ethnically diverse sample of Southern California 7(th) grade students, 99% could access the Internet at school and/or at home. This suggests that the Internet is already a potential venue for large scale health communication studies. Adolescents with more psychosocial risk factors or detrimental health behaviors were more likely to use the Internet. Therefore, if used properly, Internet interventions could effectively address the high risk populations. Additional research is needed to gain a more complete understanding of the positive and negative consequences of Internet use among adolescents.     

In search of the enactive: Introduction to special issue on enactive experience

Abstact In the decade and a half since the appearance of Varela, Thompson and Rosch's workThe Embodied Mind,enactivism has helped to put experience and consciousness, conceived of in a distinctive way, at the forefront of cognitive science. There are at least two major strands within the enactive perspective: a broad view of what it is to be an agent with a mind; and a more focused account of the nature of perception and perceptual experience. The relation between these two strands is discussed, with an overview of the papers presented in this volume.