Biological psychiatry
-
Biological psychiatry · Oct 2006
Context conditioning and behavioral avoidance in a virtual reality environment: effect of predictability.
Sustained anxiety can be modeled using context conditioning, which can be studied in a virtual reality environment. Unpredictable stressors increase context conditioning in animals. This study examined context conditioning to predictable and unpredictable shocks in humans using behavioral avoidance, potentiated startle, and subjective reports of anxiety. ⋯ Consistent with animal data, context conditioning is increased by unpredictability. These data support virtual reality as a tool to extend research on physiological and behavioral signs of fear and anxiety in humans.
-
Biological psychiatry · Oct 2006
Comparative StudyCerebellar volumes in pediatric maltreatment-related posttraumatic stress disorder.
The results of previous studies suggest structural brain differences in pediatric maltreatment-related posttraumatic stress disorder (PTSD) However, posterior fossa volumes were not examined, despite the consensus that the cerebellum is important in emotional and cognitive development. We investigated the relationship between structural volumes of the cerebellum hemispheres, vermis, brainstem, and clinical variables in pediatric maltreatment-related PTSD. ⋯ The results support cerebellar volume differences in maltreated children and adolescents with PTSD. Further studies are warranted.