Assistant Professor, Psychiatry and Medical Physics
Associate Professor, Biostatistics and Medical Informatics
"Early neglect is associated with alterations in white matter integrity and cognitive functioning" (Hanson et al., September 2013, Child Development).
The researchers found that organization of white matter in the prefrontal cortex was related to early neglect and also to the issues with planning and learning exhibited by these children. In children who had suffered early neglect, white matter in the prefrontal cortex was connected very diffusely. Prefrontal white matter in children who had not suffered such early maltreatment was organized in a very directed fashion, connecting to parts of the brain in specific ways. Diffuse brain connectivity may be related to less effective processing of information needed to plan or learn patterns.
“Prenatal Stress Induces Increased Striatal Dopamine Transporter Binding in Adult Nonhuman Primates” (Converse et al., June 2013, Biological Psychiatry).
The dopamine transporter (DAT) regulates dopamine in synapses and is linked to brain circuitry for movement, emotion, attention, and possibly ADHD. We used positron emission tomography to scan adult rhesus monkeys who had been prenatally exposed to mild daily stress and found increased DAT in striatum compared to controls. Animals with higher DAT showed greater response and slower habituation to tactile stimulation. Thus mild prenatal stress may affect both DAT and behavior in adulthood.
"Serotonin Transporter Genotype Affects Serotonin 5-HT1A Binding in Primates. " (Christian et al., Feb 2013, Journal of Neuroscience).
This research was performed to measure the 5-HT1A neurochemical endophenotype of the 5-HTTLPR polymorphism. Rhesus monkeys possess a 5-HTTLPR length polymorphism similar to humans and serve as an excellent model for studying the effects of this orthologous genetic variation on neurochemical functions related to the 5-HT system. Significantly lower 5-HT1A binding was found in s-carrier subjects throughout both cortical brain regions and the raphe nuclei. These results demonstrate that the underlying 5-HT neurochemical system is influenced by this functional polymorphism.
The Brain Imaging Core is central to the integration of behavioral and biological research at the Waisman Center IDDRC. Mental retardation and developmental disabilities, whether resulting from environmental factors or genetic factors, involve a pathological alteration of brain structure and/or function. Examination of such alterations is critical to our understanding of the causal pathways from environmental or genetic processes to behavioral outcome and for the development of preventive or ameliorative interventions.