Using enhanced FDR to find activation in FMRI images

The False Discovery Rate (FDR) criterion has been proposed for use in multiple-comparisons testing problems (Benjamini and Hochberg, 1995). A multiple testing procedure uses the FDR criterion if the procedure controls the expected proportion of false positives that are identified as active. Functional Magnetic Resonance Imaging (FMRI) are used to create images of a subject\u27s brain which show changes in blood oxygenation that can occur because of regional brain activation. The aim of many FMRI experiments is to locate regions of the brain that are activated by a specific task

Reduced functional connectivity within the mesocorticolimbic system in substance use disorders: An fMRI study of Puerto Rican young adults

Studies of the mesocorticolimbic reward system and its relationship with impulsivity and substance use disorders (SUD) have largely focused on individuals from non-minority backgrounds. This represents a significant gap in the literature particularly for minority populations who are disproportionately affected by the consequences of SUD. Using resting-state functional MRI (fMRI), we examined the coherence of neural activity, or functional connectivity, within the brain's mesocorticolimbic reward system (MCLS) in 28 young adult Puerto Ricans (ages 25-27) who were part of a population-based cohort study. Half of the sample lived in San Juan, Puerto Rico; the other half lived in the South Bronx, New York. At each of the two sites, half of the sample had a history of a SUD. Relative to those without SUD, individuals with SUD had decreased connectivity between the nucleus accumbens (NAcc) and several regions within the MCLS. This finding was true irrespective of study site (i.e., San Juan or South Bronx). Reduced connectivity within the MCLS was also associated with higher self-reported levels of impulsivity. Path analysis suggested a potential mechanism linking impulsivity, the MCLS, and SUD: impulsivity, potentially by chronically promoting reward seeking behaviors, may contribute to decreased MCLS connectivity, which in turn, may confer vulnerability for SUD. Expanding upon prior studies suggesting that alterations within the MCLS underlie SUD, our findings suggest that such alterations are also related to impulsivity and are present in a high-risk young minority population