It is widely recognized that experience with cognitive tests can influence estimates of cognitive change. Prior research has estimated experience effects at the level of groups by comparing the performance of a group of participants tested for the second time with the performance of a different group of participants at the same age tested for the first time. This twice-minus-once-tested method ...

Does personality change across the entire life course, and are those changes due to intrinsic maturation or major life experiences? This longitudinal study investigated changes in the mean levels and rank order of the Big Five personality traits in a heterogeneous sample of 14,718 Germans across all of adulthood. Latent change and latent moderated regression models provided 4 main findings: Fir...

Animals with anterior or posterior neocortical lesions as well as intact control animals were evaluated for changes in a-adrenergic sensitivity at five postoperative times. Colonic temperature decreases were measured in response to clonidine at each of the postoperative periods. The result indicated that a heightened heat-loss response was induced by clonidine that lasted 21 or more days after ...

There has recently been a great deal of interest in cognitive interventions, particularly when applied in older adults with the goal of slowing or reversing age-related cognitive decline. Although seldom directly investigated, one of the fundamental questions concerning interventions is whether the intervention alters the rate of cognitive change, or affects the level of certain cognitive measu...

This study examines 5 types of personality continuity--structural, mean-level, individual-level, differential, and ipsative--in a representative population (N=498) and a twin and sibling sample (N=548) of children and adolescents. Parents described their children on 2 successive occasions with a 36-month interval using the Hierarchical Personality Inventory for Children (I. Mervielde & F. De Fr...

Personality-relationship transactions were investigated in a general population sample of young German adults with three assessments over 8 years. Four general findings were obtained. First, personality development was characterized by substantive individual differences in change. Second, bivariate latent growth models indicated that individual differences in personality change were substantial...

OBJECTIVES We investigated how fluctuations and linear changes in health and cognitive resources influence the motivation to engage in complex cognitive activity and the extent to which motivation mediated the relationship between changing resources and cognitively demanding activities. METHOD Longitudinal data from 332 adults aged 20-85 years were examined. Motivation was assessed using a co...

The purpose of this factorial study was to establish normative data for the Italian version of the Communication Attitude Test (CAT) in order to determine whether or not the speech-associated attitude reported by Italian children who stutter (CWS) differs significantly from that of their nonstuttering peers (CWNS). Toward this end, the Italian CAT was administered to 149 CWS and 148 CWNS betwee...

chemical methods ( actinometry ) depend on the measurement of the extent to which a chemical reaction occurs under the influence of uv light. two chemical actinometers have been used in this research. in one method, the mixtures of potassium peroxidisuiphate butanol solutions were irradiated for various time intervals, and ph-changes were determined. a linear relationship was observed between t...