The few extant reports of longitudinal white matter (WM) changes in healthy aging, using diffusion tensor imaging (DTI), reveal substantial differences in change across brain regions and DTI indices. According to the last-in-first-out hypothesis of brain aging late-developing WM tracts may be particularly vulnerable to advanced age. To test this hypothesis we compared age-related changes in association, commissural and projection WM fiber regions using a skeletonized, region of interest DTI approach. Using linear mixed effects models, we evaluated the influences of age and vascular risk at baseline on seven-year changes in three indices of WM integrity and organization (axial diffusivity, AD, radial diffusivity, RD, and fractional anisotropy, FA) in healthy middle-aged and older adults (mean age = 65.4, SD = 9.0 years). Association fibers showed the most pronounced declines over time. Advanced age was associated with greater longitudinal changes in RD and FA, independent of fiber type. Furthermore, older age was associated with longitudinal RD increases in late-developing, but not early-developing projection fibers. These findings demonstrate the increased vulnerability of later developing WM regions and support the last-in-first-out hypothesis of brain aging.

The reliability, stability, and signal-to-noise ratio (SNR) of event-related potentials (ERPs) were investigated in children, adolescents, younger adults, and older adults in performance monitoring tasks. P2, N2, P3, and P2-N2 peak-to-peak amplitude showed high odd-even split reliabilities in all age groups, ranging from .70 to .90. Multigroup analyses showed that test-retest stabilities (across 2 weeks) of ERP amplitudes did not differ among the four age groups. In contrast, relative to adolescents and younger adults, SNRs were lower in children and older adults, with higher noise levels in children and lower signal power in older adults. We conclude that age differences in the SNR of stimulus-locked ERPs can be successfully compensated by the averaging procedure with about 40 trials in the average. However, age differences in baseline noise and split-half reliability should be considered when comparing age groups in single trial measures or time-varying processes with ERPs.

In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed for 101 college students (53 female) aged between 19 and 32 years (M = 23.6; SD = 2.9) over 20 weeks using a magnetic card. In order to predict the pattern of participation TPB, SCT and PAMT were used. A latent class zero-inflated Poisson growth curve analysis identified two participation patterns: regular attenders and intermittent exercisers. SCT showed the highest predictive power followed by PAMT and TPB. Impeding aspects as life stress and barriers were the strongest predictors suggesting that overcoming barriers might be an important aspect for working out on a regular basis. Self-efficacy, perceived behavioral control, and social support could also significantly differentiate between the participation patterns.

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The present paper provides a comparison of common taxonomies of foreign language learning strategies using empirical data from a Czech adaptation of the strateg y inventory SILL (Oxford, 1990). In an initial analysis none of the traditional taxonomies received strong empirical support. Based on an exploratory followup analysis we thus propose a basic three factorial model of foreign language learning strategies distinguishing 1) elaboration strategies, organisation strategies and self-control, 2) strategies of cooperative learning, and 3) motivational-emotional strategies. This three factorial model bears some similarity to O'Malley's and Chamot's (1990) classification of strategies into cognitive, metacognitive, and socioaffective strategies, although cognitive and metacognitive strategies were primarily represented by a single factor, while social and affective strategies appear to be two separated groups of strategies. Based on these first results we suggest better ways to assess foreign learning strategies in future research.

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