Passive Suicidal Ideation and Community Mental Health Resources in South Africa.

South African communities continue to experience elevated incidence and prevalence of HIV infection. Passive suicidal ideation (PSI) may be one expression of distress in high prevalence communities. We report the prevalence of PSI and examine the relationship between PSI and participation in community organizations in a semi-rural sample of South African adults (N = 594). The prevalence of PSI in the 2 weeks prior to the interview was 9.1 %. Members of burial societies (Χ (2) = 7.34; p = 0.01) and stokvels (Χ (2) = 4.1; p = 0.04) (community-based savings groups) reported significantly less PSI compared to other respondents. Using a multivariate model adjusted for demographic characteristics, psychological distress, and socioeconomic status, we found lower odds of reporting PSI for members of burial societies (OR 0.48, CI 0.25 -0.91). Participation in community organizations that provide contextually salient resources in settings with high levels of distress may be a resource for mental health.

Neuroanatomical correlates of developmental dyscalculia: combined evidence from morphometry and tractography.

Poor mathematical abilities adversely affect academic and career opportunities. The neuroanatomical basis of developmental dyscalculia (DD), a specific learning deficit with prevalence rates exceeding 5%, is poorly understood. We used structural MRI and diffusion tensor imaging (DTI) to examine macro- and micro-structural impairments in 7- to 9-year-old children with DD, compared to a group of typically developing (TD) children matched on age, gender, intelligence, reading abilities and working memory capacity. Voxel-based morphometry (VBM) revealed reduced grey matter (GM) bilaterally in superior parietal lobule, intra-parietal sulcus, fusiform gyrus, parahippocampal gyrus and right anterior temporal cortex in children with DD. VBM analysis also showed reduced white matter (WM) volume in right temporal-parietal cortex. DTI revealed reduced fractional anisotropy (FA) in this WM region, pointing to significant right hemisphere micro-structural impairments. Furthermore, FA in this region was correlated with numerical operations but not verbal mathematical reasoning or word reading. Atlas-based tract mapping identified the inferior longitudinal fasciculus, inferior fronto-occipital fasciculus and caudal forceps major as key pathways impaired in DD. DTI tractography suggests that long-range WM projection fibers linking the right fusiform gyrus with temporal-parietal WM are a specific source of vulnerability in DD. Network and classification analysis suggest that DD in children may be characterized by multiple dysfunctional circuits arising from a core WM deficit. Our findings link GM and WM abnormalities in children with DD and they point to macro- and micro-structural abnormalities in right hemisphere temporal-parietal WM, and pathways associated with it, as key neuroanatomical correlates of DD.