MedicalResearch.com Interview with: Dr Angelica Ronald Genes Environment Lifespan (GEL) laboratory Centre for Brain and Cognitive Development Department of Psychological Sciences Birkbeck, University of London London WC1E 7HX Medical Research: What are the main findings of the study? Dr. Ronald: Psychotic experiences, such as paranoia, hallucinations and disorganised thinking, are commonly reported by adolescents. Until now it has not been understood whether mild variations in psychotic experiences in the community are part of the same construct as more severe psychotic experiences in adolescence. Our findings suggest that they are. In our study, over 10,000 16-year-old adolescents in England and Wales were assessed on measures of psychotic experiences. The study identified a close link between normal, less frequent psychotic experiences and more severe and frequent experiences in the general population. A classic twin design was employed, which enabled us to conduct analyses investigating the role of genetic and environmental influences on psychotic experiences. The same genetic influences appeared to play a role across the spectrum of severity of psychotic experiences. The study found that psychotic experiences are moderately heritable in adolescence in the general population. This suggests it would be worth directing molecular genetic endeavours towards this area, which has so far received very little attention in terms of causal explanations. We also show that psychotic experiences have considerable environmental influence; in fact, environmental influence appears to play a larger role in causing psychotic experiences in adolescence than for diagnosed psychotic disorders in adults, such as schizophrenia. This result suggests a fruitful avenue will be to tackle what environmental risk factors influence adolescents to have psychotic experiences. (more…)