Learn More
We evaluated the Children's Global Assessment Scale (CGAS), an adaptation of the Global Assessment Scale for adults. Our findings indicate that the CGAS can be a useful measure of overall severity of disturbance. It was found to be reliable between raters and across time. Moreover, it demonstrated both discriminant and concurrent validity. Given these(More)
BACKGROUND Studies in abstinent methamphetamine (METH) users have demonstrated reductions in brain dopamine transporter (DAT) binding potential (BP), as well as cognitive and motor deficits, but it is not yet clear whether cognitive deficits and brain DAT reductions fully reverse with sustained abstinence, or whether behavioral deficits in METH users are(More)
Brain imaging represents a potent tool to characterize biomarkers, biological traits that are pathognomonic for specific neurological and neuropsychiatric disorders. Positron emission tomography (PET) and single photon emission computed tomography (SPECT) are imaging techniques used to identify alterations in the density and distribution of(More)
There is evidence that stress and glucocorticoids alter drug self-administration and mesolimbic dopamine (DA) activity in preclinical models. The primary purpose of this study was to test the hypothesis that glucocorticoids are associated with psychostimulant reinforcement and DA release in humans. In total, 16 healthy adults, ages 18-27 years, underwent(More)
BACKGROUND Sex differences in addictive disorders have been described. Preclinical studies have implicated the striatal dopamine system in these differences, but human studies have yet to substantiate these findings. METHODS Using positron emission tomography (PET) scans with high-specific-activity [11C] raclopride and a reference tissue approach, we(More)
OBJECTIVE Dopaminergic abnormalities in frontal-subcortical circuits have been hypothesized as the underlying pathophysiologic mechanism in Tourette's syndrome. The objective of this study was to test the hypothesis that presynaptic dopamine release from the striatum is abnormal in adults with Tourette's syndrome. METHOD Seven adults with Tourette's(More)
A challenging question that continues to plague the field of addiction is why some individuals are more vulnerable for substance use disorders than others. Several important risk factors for substance abuse have been identified in clinical studies, including trait impulsivity and environmental stress. However, the neurobiological mechanisms that underlie(More)
Several studies have examined the link between the cannabinoid CB1 receptor and several neuropsychiatric illnesses, including schizophrenia. As such, there is a need for in vivo imaging tracers so that the relationship between CB1 and schizophrenia (SZ) can be further studied. In this paper, we present our first human studies in both healthy control(More)
In quantitative dynamic PET studies, graphical analysis methods including the Gjedde-Patlak plot, the Logan plot, and the relative equilibrium-based graphical plot (RE plot) (Zhou Y., Ye W., Brasić J.R., Crabb A.H., Hilton J., Wong D.F. 2009b. A consistent and efficient graphical analysis method to improve the quantification of reversible tracer binding in(More)
Schizophrenia is a syndrome that is believed to have its onset during very early corticogenesis of the affected patient. The subsequent structural and functional cerebral variations observed in people with schizophrenia suggest an altered overall pattern of brain morphology. The alterations in cerebral structure and function in schizophrenia suggest that an(More)