Faculty Bibliography

Introduction:Dedication and training to a profession results in a certain level of expertise. This expertise, like any other skill obtained in our lifetime, is encoded in the brain and may be reflected in our brain's connectome. This property can be observed by mapping resting state connectivity. In this study, we examine the differences in resting state functional connectivity in four major networks between professional "Baduk" (Go) players and normal subjects. Methods:Resting state fMRI scans were acquired for professional "Baduk" (Go) players and normal controls. Major resting state networks were identified using independent component analysis and compared between the two groups. Networks which were compared include the default mode network, the left and right fronto-parietal network, and the salience network. Results:We found that normal subjects showed increased connectivity within certain areas of each target network. Professional players, however, showed higher connectivity to regions outside the traditional regions of each given network. Close examination of these regions revealed that regions shown to have higher connectivity in professional players have been revealed to be relevant in expertise for board games. Conclusion:The findings in this study suggest that continuous training results in greater integration between regions and networks, which are necessary for high-level performance. The differences observed in our study between normal controls and professional players also shed light on the difference in brain connectivity which can arise through lifestyle and specialization in a specific field.

BACKGROUND:African American adults achieve smaller amounts of weight loss than their white counterparts when exposed to the same intervention and are more likely to regain weight during long-term follow-up. OBJECTIVE:To identify perceived motivators, barriers, and facilitators to weight loss and behavior change among African American adults. METHODS:Two focus groups were conducted between April and May 2015 at an urban community health center in Baltimore City, Maryland. A total of 13 participants took part in the discussions. Eligible participants were obese (BMI 30+) African American adults aged 21-70 who had at least one obesity-related comorbidity. Discussion questions were designed to identify the personal, social, and environmental factors that influence weight loss and behavior change among urban minority populations. RESULTS:Statements were first classified as a motivator, barrier, or facilitator, then divided further as a personal, social, or environmental factor influencing weight loss and behavior change. Among the findings, several novel motivators (reducing or eliminating medication, improving physical intimacy) and barriers (personal transportation, lack of access to scales) emerged that were not previously characterized in the existing literature. CONCLUSIONS:This study was intended to provide preliminary evidence that may be used to guide the development of innovative and culturally relevant weight-loss interventions in the future. Results are applicable to similar urban minority populations.

Increasing evidence indicates that multiple structures in the brain are associated with intelligence and cognitive function at the network level. The association between the grey matter (GM) structural network and intelligence and cognition is not well understood. We applied a multivariate approach to identify the pattern of GM and link the structural network to intelligence and cognitive functions. Structural magnetic resonance imaging was acquired from 92 healthy individuals. Source-based morphometry analysis was applied to the imaging data to extract GM structural covariance. We assessed the intelligence, verbal fluency, processing speed, and executive functioning of the participants and further investigated the correlations of the GM structural networks with intelligence and cognitive functions. Six GM structural networks were identified. The cerebello-parietal component and the frontal component were significantly associated with intelligence. The parietal and frontal regions were each distinctively associated with intelligence by maintaining structural networks with the cerebellum and the temporal region, respectively. The cerebellar component was associated with visuomotor ability. Our results support the parieto-frontal integration theory of intelligence by demonstrating how each core region for intelligence works in concert with other regions. In addition, we revealed how the cerebellum is associated with intelligence and cognitive functions.

Dysfunction of corticostriatal loops has been proposed to underlie certain cognitive and behavioral problems associated with various neuropsychiatric disorders, such as obsessive-compulsive disorder (OCD) characterized by repetitive, unwanted thoughts, and behaviors. Although functional abnormalities in the loops involving the orbitofronto-striato-thalamic (OFST) circuitry in patients with OCD have been reported, our understanding of a link between disruptions in the architecture of the intrinsic functional network of the OFST circuit and their symptoms remain incomplete. Using resting-state functional MRI in conjunction with unsupervised clustering and multilevel functional connectivity (FC) techniques, FC of the OFST network and its topological organization in 61 OCD patients versus 61 matched controls were characterized. Patients exhibited disruptions in small-world properties of the OFST circuit, which indicates an imbalance between functional integration and segregation. Patients also showed decreased FC between the central orbitofrontal cortex and dorsomedial striatum but increased FC between the medial thalamus and striatal areas. Using one of the largest samples of unmedicated OCD patients to date, our findings provide evidence supporting the OFST dysconnection hypothesis in OCD as a basic pathophysiological mechanism underlying the disorder, showing the disruption of FC between specific cortical, striatal, and thalamic clusters and aberrant topological patterns of the OFST circuit. Hum Brain Mapp 38:109-119, 2017. © 2016 Wiley Periodicals, Inc.

OBJECTIVE:Although disconnection syndrome has been considered a core pathophysiologic mechanism of schizophrenia, little is known about the temporal behavior of mismatch negativity (MMN) generators in individuals with schizophrenia or clinical high risk (CHR) for psychosis. METHODS:MMN was assessed in 29 schizophrenia patients, 40 CHR subjects, and 47 healthy controls (HCs). Individual realistic head models and the minimum L2 norm algorithm were used to generate a current source density (CSD) model of MMN. The strength and time course of MMN CSD activity were calculated separately for the frontal and temporal cortices and were compared across brain regions and groups. RESULTS:Schizophrenia patients and CHR subjects displayed lower MMN CSD strength than HCs in both the temporal and frontal cortices. We found a significant time delay in MMN generator activity in the frontal cortex relative to that in the temporal cortex in HCs. However, the sequential temporo-frontal activities of MMN generators were disrupted in both the schizophrenia and CHR groups. CONCLUSIONS:Impairments and altered temporal behavior of MMN multiple generators were observed even in individuals at risk for psychosis. SIGNIFICANCE:These findings suggest that aberrant MMN generator activity might be helpful in revealing the pathophysiology of schizophrenia.

Prolonged glucocorticoid (GC) administration causes secondary osteoporosis (GIOP) and non-traumatic osteonecrosis. LLP2A-Ale is a novel bone-seeking compound that recruits mesenchymal stem cells to the bone surface, stimulates bone formation, and increases bone mass. The purpose of this study was to determine if treatment with LLP2A-Ale alone or in combination with parathyroid hormone (PTH) could prevent or treat GIOP in a mouse model. Four-month-old male Swiss-Webster mice were randomized to a prevention study with placebo, GC (day 1-28), and GC + LLP2A-Ale (IV, day 1) or a treatment study with placebo, GC (days 1-56), GC + LLP2A-Ale (IV, day 28), GC + PTH, and GC + LLP2A-Ale + PTH (days 28-56). Mice were killed on day 28 (prevention study) or on day 56 (treatment study). The study endpoints included bone mass, bone strength, serum markers of bone turnover (P1NP and CTX-I) and angiogenesis (VEGF-A), surface-based bone turnover, and blood vessel density. LLP2A-Ale prevented GC-induced bone loss and increased mechanical strength in the vertebral body (days 28 and 56) and femur (day 56). LLP2A-Ale, PTH, and LLP2A-Ale + PTH treatment significantly increased the mineralizing surface, bone formation rate, mineral apposition rate, double-labeled surface, and serum P1NP level on day 56. LLP2A-Ale and PTH treatment increased femoral blood vessel density and LLP2A-Ale increased serum VEGF-A on day 28. Therefore, LLP2A-Ale monotherapy could be a potential option to both prevent and treat GC-induced osteoporosis and bone fragility.

Gender inequalities shape the experience of food insecurity among women living with HIV (WLHIV). We systematically reviewed the impact of food insecurity on sexual risk behaviors and antiretroviral therapy (ART) adherence among WLHIV. We included qualitative or quantitative peer-reviewed articles, extracted data in duplicate, and assessed rigor. Seven studies, from sub-Saharan Africa, North America, and Europe, met inclusion criteria. Food insecurity was associated with increased sexual risk through transactional sex and inability to negotiate safer sex. Hunger and food insecurity were barriers to ART initiation/adherence. Multidimensional programming and policies should simultaneously address poverty, gender inequality, food insecurity, and HIV.