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Colich, N. L.

Publications and source records attributed to Colich, N. L..

2 recordsLinked to original sources

Biological Aging in Childhood and Adolescence Following Experiences of Threat and Deprivation: A Systematic Review and Meta-Analysis

Life history theory argues that exposure to early-life adversity (ELA) accelerates development, although existing evidence for this varies. We present a meta-analysis and systematic review testing the hypothesis that ELA involving threat (e.g., violence exposure) will be associated with accelerated biological aging across multiple metrics, whereas exposure to deprivation (e.g., neglect, institutional rearing) and low-socioeconomic status (SES) will not. We meta-analyze 46 studies (n=64,925) examining associations of ELA with pubertal timing and cellular aging (telomere length and DNA methylation age), systematically review 19 studies (n=2276) examining ELA and neural markers of accelerated development (cortical thickness and amygdala-prefrontal cortex functional connectivity) and evaluate whether associations of ELA with biological aging vary according to the nature of adversity experienced. ELA overall was associated with accelerated pubertal timing (d=-0.12) and cellular aging (d=-0.32). Moderator analysis revealed that ELA characterized by threat (d=-0.26), but not deprivation or SES, was associated with accelerated pubertal development. Similarly, exposure to threat-related ELA was associated with accelerated cellular aging (d=-0.43), but not deprivation or SES. Systematic review revealed associations between ELA and accelerated cortical thinning, with threat-related ELA consistently associated with thinning in ventromedial prefrontal cortex, and deprivation and SES associated with thinning in frontoparietal, default, and visual networks. There was no consistent association of ELA with amygdala-PFC connectivity. These findings suggest specificity in the types of early environmental experiences associated with accelerated biological aging and highlight the importance of evaluating how accelerated aging contributes to health disparities and whether this process can be mitigated through early intervention.

neuroscience

Sex differences in the effects of gonadal hormones on white matter microstructure development in adolescence

Adolescence, the transition between childhood and adulthood, is characterized by rapid brain development in white matter (WM) that is attributed in part to surges in gonadal hormones. To date, however, there have been no longitudinal investigations of the effects of gonadal hormones on WM development in adolescents. We acquired T1-weighted and diffusion-weighted MRIs at two timepoints and saliva samples from 80 adolescents (52 females [11.10{+/-}1.05 years at Time 1; 12.75{+/-}1.37 years at Time 2] and 28 males [ages 11.91{+/-}0.88 years at Time 1; 13.79{+/-}0.95 years at Time 2] who were matched on pubertal stage at Time 1. We estimated mean fractional anisotropy (FA) from 10 major WM tracts and assayed levels of testosterone (in both sexes) and estradiol (in females only). We used linear regression models to test whether interactions between sex and changes in testosterone levels significantly explained changes in FA. Sex significantly moderated the associations between changes in testosterone and changes in FA within the corpus callosum, inferior fronto-occipital fasciculus (IFOF), uncinate fasciculus (UF), and cingulum cingulate (all ps<0.05): whereas these associations were positive in females, they were not significant in males. Females also exhibited positive associations between changes in estradiol and changes in UF, IFOF, and corticospinal FA (all ps<0.05). Our findings indicate that sex differences in WM microstructure of tracts supporting cognitive control, response inhibition, and emotion regulation are explained by differences in changes in testosterone, and have important implications for understanding sex differences in brain development and psychosocial behaviors during the pubertal transition.

neuroscience