Projects:MorphometryFrontalCircuitry
Objective: To see how morphometry of various frontal circuitry structures relates to substance use disorder in schizophrenia.
Progress: In collaboration with Nancy Koven, Ph.D. at Bates College, we have been conducting volumetric investigations of subregions within brain reward circuitry in healthy adults, patients with schizophrenia and a co-occurring substance use disorder (SUD), and patients with schizophrenia without a history of SUD. 3D-Slicer is being used to trace the nucleus accumbens, orbitofrontal cortex (OFC), and several regions within the anterior cingulate gyrus. With regard to the OFC, preliminary findings on 10 subjects per group indicate that patients with schizophrneia, both with and without co-occurring SUD, have less bilateral OFC volume relative to controls. In comorbid patients, larger right OFC volume was associated with improved inhibitory control on neuropsychological testing. In patients without co-occurring SUD, smaller left OFC volume was associated with poorer inhibitory control. With regard to the anterior cingulate gyrus, analyses indicated that patients with comorbid SUD had smaller bilateral dorsal and rostral subregions relative to healthy controls. Further analysis indicated that patients scored lower on tests of inhhibitory control relative to controls. Test of mediation, however, indicated that dorsal and rostral subregion volumetry did not mediate this neuropsychological dysfunction in this sample.
Key Investigators:
- Dartmouth: Robert Roth, Laura Flashman, Andrew Saykin, Thomas McAllister
- Isomics: Steve Pieper