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Matsuba MK Pratt MW Norris JE Mohle E Alisat S McAdams DP 《Journal of personality》2012,80(4):1091-1115
Previous qualitative studies have identified themes of generativity and identity development in the interviews of environmental activists (Chan, 2009 ; Horwitz, 1996 ), suggesting their importance as motives for environmental behavior. The purpose of our study was to extend this work by identifying positive relationships between identity maturity, generativity, and environmentalism using quantitative methodologies. To explore these relationships, we designed quasi‐experimental and correlational studies. We recruited 54 environmental activists and 56 comparison individuals, half of whom were youth (mean age = 22 years) and the other half midlife adults (mean age = 43 years). Sixty‐three percent of our sample was female. Participants completed several environmental, generativity, and identity questionnaires. We found that activists and comparison individuals differed on the identity maturity, generativity, and environmental measures overall. Further, greater identity maturity and generativity were associated with higher environmental engagement. And generativity was found to mediate the relation between identity maturity and environmentalism. Our findings suggest that engaging in generative behaviors may be an important part of the process in forming an environmental identity and engaging in environmental actions. 相似文献
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This study investigated the occurrence of depressive symptoms prior to age 36 months as retrospectively reported by parents of preschoolers with clinical depression. The study provides some of the first empirical data on the manifestations of depressive symptoms during the toddler period, advancing existing theoretical and case‐report literature. A sample of 301 (depressed, disruptive, and healthy) children between the ages of 3.0 and 6.0 years were screened and oversampled for depressive symptoms from community sites. Primary caregivers (parents) were interviewed about their child's symptoms of depression (as well as other symptoms of mental disorders and developmental parameters), and age of first onset of depressive symptoms was ascertained. Findings suggest that clinical‐level symptoms of depression may arise as early as age 24 months. The domain of negative self‐concept during the toddler period evidenced by self‐deprecation and difficulty making choices emerged as the two strongest variables predictive of preschool depression. Our results suggest that prospective empirical studies of depressive symptoms in children younger than 3 years of age should now be undertaken. 相似文献
948.
The influence of motor skill learning on movement-related brain activity was investigated using electroencephalography. Previous research has indicated that experienced performers display movement-related cortical potentials (MRCPs) of smaller amplitude and later onset compared to novices. Unfortunately, previous studies have lacked ecological validity with experimenters recording the MRCP prior to simple motor tasks and applying the results to more complex motor skills. This study replicated previous research using an ecologically valid motor skill; recording the MRCP from a group of experienced guitarists and a control group of non-musicians while they played a simple scale on the guitar. Results indicated no difference between groups in early motor planning. In contrast, the later, negative slope and motor potential components were of smaller amplitude and the negative slope began later in the experienced guitarists. The data may indicate that, for experienced guitarists, a reduced level of effort is required during the motor preparation phase of the task. These findings have implications for musical instrument learning as well as motor skill acquisition in general. 相似文献
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The local dynamic stability of trunk movements was assessed during repetitive lifting using nonlinear Lyapunov analyses. The goal was to assess how varying the load-in-hands affects the neuromuscular control of lumbar spinal stability. Thirty healthy participants (15M, 15F) performed repetitive lifting at 10 cycles per minute for three minutes under two load conditions: zero load and 10% of each participant's maximum back strength. Short- and long-term maximum finite-time Lyapunov exponents (λ(max-s) and λ(max-l)), describing responses to infinitesimally small perturbations, were calculated from the measured trunk kinematics to estimate the local dynamic stability of the system. Kinematic variability was also assessed using mean standard deviations (MeanSD) across cycles. The results of a mixed-design repeated-measures ANOVA showed that increasing the load lifted significantly reduced λ(max-s) (μ(0%-LOAD)=0.379, μ(10%-LOAD)=0.335, p<.001), but not λ(max-l) (μ(0%-LOAD)=0.46E-03, μ(10%-LOAD)=2.41E-03, p=.055) or MeanSD (μ(0%-LOAD)=2.57, μ(10%-LOAD)=2.89, p=.164). There were no between-subject effects of sex, or significant interactions (α<.05). The present findings indicated improved dynamic spinal stability when lifting the heavier load; meaning that as muscular and moment demands increased, so too did participants' abilities to respond to local perturbations. These results support the notion of greater spinal instability during movement with low loads due to decreased muscular demand and trunk stiffness, and should aid in understanding how lifting various loads contributes to occupational low back pain. 相似文献
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Performing under pressure: gaze control, decision making and shooting performance of elite and rookie police officers 总被引:1,自引:0,他引:1
Gaze of elite (E) and rookie (R) officers were analyzed as they faced a potentially lethal encounter that required use of a handgun, or inhibition of the shot when a cell phone was drawn. The E shot more accurately than the R (E 74.60%; R 53.80%) and made fewer decisions errors in the cell condition when 18.50% of E and 61.50% of R fired at the assailant. E and R did not differ in duration of the draw/aim/fire phases, but the R's motor onsets were later, during the final second compared to the E's final 2.5 s. Across the final six fixations the E increased the percent of fixations on the assailant's weapon/cell to 71% and to 86% on hits, compared to a high of 34% for the R. Before firing, the R made a rapid saccade to their own weapon on 84% of trials leading to a failure to fixate the assailant on 50% of trials as they fired. Compared to the R, the E had a longer quiet eye duration on the assailant's weapon/cell prior to firing. The results provide new insights into officer weapon focus, firearms training and the role of optimal gaze control when under extreme pressure. 相似文献