A Test of the Adams-Creamer Decay Hypothesis for the Timing of Motor Responses

The Adams-Creamer hypothesis states that S uses the decay of proprioceptive feedback from an early portion of a movement to cue a timed response at some later time. This hypothesis was tested by creating passive left-arm movement in one group and withholding it from another, and having Ss make a right-hand response when exactly 2.0 sec. had elapsed since the end of the movement Ss with left-arm feedback had less absolute and algebraic error, and greater within-S consistency than did the no-movement control Ss and, when KR was withdrawn, Ss with left-arm movement regressed less than did Ss without the left-arm movement, which provided 2 lines of support for the decay hypothesis.     

The Force/Force-Variability Relationship Under Controlled Temporal Conditions

Previously, an inverted U relationship between force and force variability was demonstrated in both static and dynamic responses. Recent research suggests that the inverted U function may be due to a lack of control of the temporal aspects of the response. To investigate this hypothesis, we examined the relationship between force and force variability in rapid movements under controlled temporal conditions. Subjects (N = 4) made rapid reversal responses with a horizontal lever (using elbow flexion and extension) such that the time to reversal (160 ms) and the distance to reversal (45°) were held constant in each of six load conditions (either 0, .260, .520, .780,1.040, or 1.560 kg added to the lever). When time to reversal and time to peak acceleration were held constant, a curvilinear relationship between force and force variability resulted, suggesting that the inverted U function is related to control of the temporal aspects of the response.     

Still cautious: Personality characteristics of extremely low birth weight adults in their early 30s

Extremely low birth weight survivors (ELBW; <1000 g) display a personality style characterized by cautiousness, shyness, and risk aversion in their 20s. We examined whether non-impaired ELBW survivors were still more cautious than their normal birth weight (NBW) peers at ages 30–35 and assessed the stability of this personality characteristic across approximately a decade in the oldest known cohort of ELBW survivors. Of the 154 participants tested at ages 22–26, 111 (i.e., 72%) of them returned approximately 10 years later [i.e., 69% (49/71) ELBW and 75% (62/83) NBW], and once again they completed the Eysenck Personality Questionnaire-Revised (EPQ-R). We created the same theoretically and empirically derived composite measure of cautiousness at each visit by summing the EPQ-R psychoticism scale (reverse scored) and the EPQ-R lie scale. We found that ELBW adults reported higher cautiousness than their NBW counterparts at ages 30–35. We also found that levels of cautiousness remained stable over approximately 10 years in both groups. Our findings suggest that individuals born at ELBW were more cautious than NBW peers and that this personality characteristic remained stable into their early 30s. The present study appears to be the first empirical demonstration of personality stability among adult ELBW survivors.     

Repeated measurement of salivary cortisol within and across days among shy young adults

Temperamental shyness emerges early in childhood and remains relatively stable throughout development and has been associated with high and low levels of the stress hormone cortisol. Studies examining the relation between shyness and cortisol have been limited because they have traditionally collected only one measure of cortisol on a single day in the laboratory, restricting the reliability and diurnal profile of the measure in the participant’s everyday environment. We collected 15 saliva samples across three separate days (i.e., upon waking, +60 min post-waking, +8 h post-waking, +10 h post-waking, and bedtime) in a sample of healthy young adults selected for high and low shyness in order to characterize a portion of the diurnal cortisol rhythm. Overall, shy individuals demonstrated relatively lower cortisol across the day and across multiple mornings than non-shy adults. Higher self-reported social anxiety across multiple measures was also related to lower total cortisol levels across all participants. The present study replicates and extends our previous findings of low salivary cortisol measured in the laboratory in shy adults to repeated measurement in their everyday environments.     

Methods for second order meta-analysis and illustrative applications

This paper presents methods for second order meta-analysis along with several illustrative applications. A second order meta-analysis is a meta-analysis of a number of statistically independent and methodologically comparable first order meta-analyses examining ostensibly the same relationship in different contexts. First order meta-analysis greatly reduces sampling error variance but does not eliminate it. The residual sampling error is called second order sampling error. The purpose of a second order meta-analysis is to estimate the proportion of the variance in mean meta-analytic effect sizes across multiple first order meta-analyses attributable to second order sampling error and to use this information to improve accuracy of estimation for each first order meta-analytic estimate. We present equations and methods based on the random effects model for second order meta-analysis for three situations and three empirical applications of second order meta-analysis to illustrate the potential value of these methods to the pursuit of cumulative knowledge.     

Lay concepts of health and illness from a developmental perspective

Abstract

The concepts of children, adolescents and their mothers with regard to different aspects of health and illness in general and five specific diseases were explored in this study. An exploration with fully standardised questions and open answers was subjected to a content analysis. A reliable rating system was developed to score the sophistication of the answers. The study included 99 Ss of the age groups 5, 8, 12 and 16 years, as well as 48 mothers of the children. Many children and adolescents were able to define health positively (well-being) and not merely as the absence of illness. The definition of illness in general was frequently composed of somatic symptoms and disorders, feeling poorly and things one would like to accomplish but can't. The causality explanations of illness in general were dominated by contagion. The concepts of the older children and the mothers were richer, more elaborated, less concrete and less action-oriented than those of the younger children. However, abstract formulations and complex aspects of illness were very rarely expressed. In addition, concepts regarding the characteristics (definition, symptoms, causality, treatment and prevention) of five diseases (cold, measles, heart infarction, cancer and AIDS) were measured. The pattern of results was strongly influenced by age. By and large, the development of most disease concepts was linear with significant differences between age groups. Conversely, within a given age group, significant differences were found in the cognitive level of disease characteristics, either with respect to the same disease or between different diseases (“horizontal shifts”).