Age-related, multivariate associations between white matter microstructure and behavioral performance in three executive function domains.

The executive function (EF) domains of working memory (WM), response inhibition (RI), and set shifting (SS) show maturational gains and are linked to neuroimaging-measured brain changes. This study explored ways in which maturation-linked differences in EF abilities are systematically associated with white matter microstructural differences from adolescence into young adulthood. Diffusion tensor imaging (DTI) and nine neurocognitive tests were collected from 120 healthy subjects ages 12-24. Analyses across the white matter skeleton were performed, focusing on fractional anisotropy (FA). Data were 'fused' using a multivariate technique (CCA+jICA), producing four independent components (ICs) depicting white matter FA values that covaried with test performance. Correlations between age and IC loading coefficients identified three EF-DTI profiles that may change developmentally. In one, SS performance was linked to greater reliance on the FA of ventral brain tracts, and less on dorsal tracts with age. In another, white matter microstructure was related to a pattern of strong WM and weak SS that became more pronounced with age. A final IC revealed that younger individuals with low RI and high WM/SS skills typically matured out of this cognitive imbalance, underscored by white matter changes with age. These novel multivariate results begin to emphasize the complexity of brain structure-cognition relationships in adolescents and young adults.

Using the social ecological model to identify challenges facing Latino immigrants.

BACKGROUND: New Latino immigrant populations face challenges and barriers when arriving in new immigrant destinations. OBJECTIVE: To better understand the challenges faced by Latino immigrants in a new immigrant destination by using the Social Ecological Model. DESIGN: This study solicited the perceptions of key informants and Latino immigrant participants through qualitative data collection methods to understand how to address and decrease barriers to healthcare services and community resources. SAMPLE: Researchers conducted semi-structured interviews with two groups of respondents: 13 key informants and 30 Latino immigrants. MEASUREMENTS: Data were analyzed using thematic analysis and categorized based on the Social Ecological Model. RESULTS: Themes identified at the individual and interpersonal levels of the Social Ecological Model include fear of deportation and stress. Themes at the community level include cultural differences, discrimination, and a lack of exposure of the majority community to Latino immigrants. At the system level, researchers identified language barriers, the cost of healthcare, and housing. At the policy level, researchers identified legal status and occupational exploitation as challenges for this community. CONCLUSION: Understanding the challenges faced by Latino immigrants requires multi-level interventions to address barriers that prevent new immigrants from accessing community resources.