Linking vitamin D status, executive functioning and self-perceived mental health in adolescents through multivariate analysis: A randomized double-blind placebo control trial.

The aim of the present randomized double-blind placebo control trial was to investigate if vitamin D supplementation had an effect on vitamin D status, executive functioning and self-perceived mental health in a group of Norwegian adolescents during winter time. Fifty adolescents were randomly assigned into an intervention group (vitamin D pearls) or a control group (placebo pearls). Before (pre-test in December/January) and after (post-test in April/May) the intervention period the participants were exposed to a test procedure, consisting of blood draw, completion of cognitive tests (Tower of Hanoi and Tower of London), and the Youth Self-report version of the Child Behavior Checklist. Multivariate data analysis showed that participants with low vitamin D status scored worse on the Tower of London tests and the more difficult sub-tasks on the Tower of Hanoi tests. They also had a tendency to report higher frequency of externalizing behavior problems and attention deficit. At pre-test, the overall mean vitamin D status measured as 25-hydroxy vitamin D was 42 nmol/L, defining deficiency (Intervention group = 44 nmol/L, Control group = 39 nmol/L). However, vitamin D supplementation caused a significant increase in vitamin D status resulting in a sufficient level in the Intervention group at post-test (mean 62 nmol/L). The results also revealed that the intervention group improved their performance on the most demanding sub-tasks on the ToH. Overall, the study indicates that vitamin D status in adolescents may be important for both executive functioning and mental health.

Psychopathy and the ability to read the "language of the eyes": divergence in the psychopathy construct.

The capacity to interpret others people's behavior and mental states is a vital part of human social communication. This ability, also called mentalizing or Theory of Mind (ToM), may also serve as a protective factor against aggression and antisocial behavior. This study investigates the relationship between two measures of psychopathy (clinical assessment and self-report) and the ability to identify mental states from photographs of the eye region. The participants in the study were 92 male inmates at Bergen prison, Norway. The results showed some discrepancy in connection to assessment methodology. For the self-report (SRP-III), we found an overall negative association between mental state discrimination and psychopathy, while for the clinical instrument (PCL-R) the results were more mixed. For Factor 1 psychopathic traits (interpersonal and affective), we found positive associations with discrimination of neutral mental states, but not with the positive or negative mental states. Factor 2 traits (antisocial lifestyle) were found to be negatively associated with discrimination of mental states. The results from this study demonstrate a heterogeneity in the psychopathic construct where psychopathic traits related to an antisocial and impulsive lifestyle are associated with lower ability to recognize others' mental states, while interpersonal and affective psychopathic traits are associated with a somewhat enhanced ability to recognize others' emotional states.

Psychological hardiness predicts neuroimmunological responses to stress.

Psychological hardiness characterizes people who remain healthy under psychosocial stress. The present exploratory study investigates possible links between hardiness and several immune and neuroendocrine markers: IL-6, IL-12, IL-4, IL-10, & neuropeptide-Y. A total of 21 Norwegian navy cadets were studied in the context of a highly stressful military field exercise. Blood samples were collected midway, and again late in the exercise when stress levels were highest. Psychological hardiness (including commitment, control, and challenge) was measured two days before the exercise. While all subjects scored high in hardiness, some were high only in commitment and control, but relatively low in challenge. These "unbalanced" hardiness subjects were also more stress reactive, showing suppressed proinflammatory cytokines (IL-12), increased anti-inflammatory cytokines (IL-4, IL-10), and lower neuropeptide-Y levels as compared to the hardiness-balanced group. This study thus shows that being high in hardiness with a balanced profile is linked to more moderate and healthy immune and neuroendocrine responses to stress.