SynopsisSocial phobia was studied in a North Carolina community, using DSM-III criteria. Two kinds of comparison were made: social phobia v. non-social phobia, and comorbid social phobia v. non-comorbid social phobia. Six-month and lifetime prevalence rates were 2·7 and 3·8% respectively. Social phobia had an early onset, lasted a long time and rarely recovered. Predictors of good outcome recovery in a logistic regression analysis were onset of phobia after age 11, absence of psychiatric comorbidity and greater education. The disorder was often missed in medical consultation. Increased rates of psychiatric comorbidity existed, especially for other anxiety disorders and for schizophrenia/schizophreniform disorder. There was increased risk of neurological disorder. Social phobia was also associated with an increased rate of suicide attempts, antisocial behaviour and impaired school performance during adolescence, impaired medical health, increased health-seeking behaviour, poor employment performance, reduced social interaction and impaired social support. Comorbidity accounted for some, but not all observed differences.

This review considers the research to date on the role of nutrition in cognitive development in children, with a particular emphasis on the relatively neglected post-infancy period. Undernutrition and deficiencies of iodine, iron, and folate are all important for the development of the brain and the emergent cognitive functions, and there is some evidence to suggest that zinc, vitamin B12, and omega-3 polyunsaturated fatty acids may also be important. Considerations for future research include a focus on the interactions between micronutrients and macronutrients that might be influential in the optimization of cognitive development; investigation of the impact of nutritional factors in children after infancy, with particular emphasis on effects on the developing executive functions; and selection of populations that might benefit from nutritional interventions, for example, children with nutrient deficiencies or those suffering from attention deficit-hyperactivity disorder and dyslexia.

Based on research demonstrating associations between folate, B-12 and B-6 vitamins and cognition and mood, we investigated the effects of short-term supplementation in 211 healthy younger, middle-aged and older women who took either 750 microg of folate, 15 microg of vitamin B-12, 75 mg of vitamin B-6 or a placebo daily for 35 d. In addition, we examined associations between dietary intake of these vitamins and cognition and mood. Usual dietary intake status was estimated using a retrospective, self-report, quantified food frequency questionnaire. Participants completed alternate forms of standardized tests of cognitive processing resources, memory, executive function, verbal ability and self-report mood measures before and after supplementation. Supplementation had a significant positive effect on some measures of memory performance only, and no effect on mood. Dietary intake status was associated with speed of processing, recall and recognition and verbal ability.