title: Frontostriatal connectivity in children during working memory and the effects of prenatal methamphetamine, alcohol, and polydrug exposure.
abstract: Various abnormalities in frontal and striatal regions have been reported in children with prenatal alcohol and/or methamphetamine exposure. In a recent fMRI study, we observed a correlation between accuracy on a working-memory task and functional activation in the putamen in children with prenatal methamphetamine and polydrug exposure. Because the putamen is part of the corticostriatal motor loop whereas the caudate is involved in the executive loop, we hypothesized that a loss of segregation between distinct corticostriatal networks may occur in these participants. The current study was designed to test this hypothesis using functional connectivity MRI. We examined 50 children ranging in age from 7 to 15, including 19 with prenatal methamphetamine exposure (15 of whom had concomitant prenatal alcohol exposure), 13 with prenatal exposure to alcohol but not methamphetamine, and 18 unexposed controls. We measured the coupling between blood oxygenation level dependent (BOLD) fluctuations during a working-memory task in four striatal seed regions and those in the rest of the brain. We found that the putamen seeds showed increased connectivity with frontal brain regions involved in executive functions while the caudate seeds showed decreased connectivity with some of these regions in both groups of exposed subjects compared to controls. These findings suggest that localized brain abnormalities resulting from prenatal exposure to alcohol and/or methamphetamine lead to a partial rewiring of corticostriatal networks. These results represent important progress in the field, and could have substantial clinical significance in helping devise more targeted treatments and remediation strategies designed to better serve the needs of this population.
authors.affiliation: Developmental Cognitive Neuroimaging Laboratory, Children's Hospital Los Angeles and Department of Pediatrics, University of Southern California, CA 90027, USA.
authors.forename: Florence F
authors.initials: FF
authors.lastname: Roussotte
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Rudie
authors.forename: Lynne
authors.initials: L
authors.lastname: Smith
authors.forename: Mary J
authors.initials: MJ
authors.lastname: O'Connor
authors.forename: Susan Y
authors.initials: SY
authors.lastname: Bookheimer
authors.forename: Katherine L
authors.initials: KL
authors.lastname: Narr
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Sowell
mesh_terms: D000293:Adolescent; D000428:Alcohol Drinking / Q000009:adverse effects*; D001921:Brain / Q000002:abnormalities* / Q000187:drug effects; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D002492:Central Nervous System Depressants / Q000009:adverse effects; D000697:Central Nervous System Stimulants / Q000009:adverse effects; D002648:Child; D003342:Corpus Striatum / Q000187:drug effects / Q000503:physiopathology*; D000431:Ethanol / Q000008:administration & dosage / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term; D008694:Methamphetamine / Q000008:administration & dosage / Q000009:adverse effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000209:etiology / Q000473:pathology*; D011699:Putamen / Q000187:drug effects / Q000503:physiopathology; D019966:Substance-Related Disorders / Q000150:complications
chemical_list: D002492:Central Nervous System Depressants; D000697:Central Nervous System Stimulants; D000431:Ethanol; D008694:Methamphetamine