In pursuit of its long-standing commitment to characterizing the neurochemical, neurogenetic, and neuropsychological contributions to neural systems function and development relevant to mental illness, the Section on Integrative Neuroimaging (SoIN) has made tremendous progress in building two unprecedented scientific resources: first, a unique multimodal positron emission tomography dataset that will soon be able to answer fundamental questions about dopamine pre- and post-synaptic function in a more comprehensive way than previously possible;and, second, a neurodevelopmental dataset that incorporates structural and functional magnetic resonance-based brain imaging, and, in conjunction with the Section on Behavioral Endocrinology, precise, state-of-the-art endocrinological measurements of pubertal status. These extensive and comprehensive ongoing data acquisition efforts have yielded a growing repository of integrated information about the brain, which will permit both novel analyses synthesizing disparate but interrelated indices of pre- and post-synaptic dopamine functioning and discovery of critical genetic and endocrinological factors guiding neurodevelopment. There have been achievements on several fronts, including multimodal elaboration of normative social information processing and identification of novel genetic associations with cortical activation to mnemonic challenge. Because the neural mechanisms contributing to altered processing of social cues in neuropsychiatric conditions such as schizophrenia, autism and Williams syndrome remain mysterious, preventing development of targeted biological therapies, we have employed integrated multimodal methods to investigate the dynamics of brain networks critical for processing socially salient stimuli. We have been able to characterize functional correlates of facial expression viewing with unprecedented detail by measuring sustained blood-oxygenation level-dependent (BOLD) signal (providing excellent spatial resolution;from fMRI) and transient gamma-band activity (GBA;providing excellent temporal resolution;from MEG) responses to environmentally valid, dynamic emotional cues. We demonstrated for the first time that midbrain presynaptic dopamine synthesis (from PET) predicts BOLD and GBA signals in important socio-emotional brain regions such as the superior temporal sulcus (STS) (Jabbi et al., 2013) and have now extended this work to show that both transient beta-band activity and BOLD signal show concomitant modulation over time as facial expressions emerge on a viewed face. (Jabbi et al., 2014) Other recent work has focused on defining the impact of gene variants associated with schizophrenia and has begun to evaluate new hypotheses about how sequelae of common genetic variation intersects with the biology of mental illness. This includes testing of several epistatic hypotheses, which has become increasingly critical (Eisenberg et al., 2013) and is exemplified by several novel neuroimaging genetic experiments, such as those confirming previous preclinical interactions between SLC12A2 and DISC1. (Callicott et al., 2013) This also includes testing hypotheses generated by large-scale, data-driven genome-wide association analyses, as was executed in a high-profile, multistep investigation of allelic variation in SCN2A, a gene coding for a sodium channel protein, which shows not only genome-wide association with general cognitive ability, but also association with working-memory induced prefrontal activation. (Dickinson et al., 2014) In summary, the Section on Integrative Neuroimaging has made substantial progress toward advancing its long-range, central research aims and with further data acquisition will be well-poised to address several pressing scientific questions of high impact to the neuroscience field.
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