Variability in frontotemporal brain structure: the importance of recruitment of African Americans in neuroscience research

• Published in: PloS one 2010-10, Vol.5 (10), p.e13642-e13642
• Main Authors: Isamah, Nneka, Faison, Warachal, Payne, Martha E, MacFall, James, Steffens, David C, Beyer, John L, Krishnan, K Ranga, Taylor, Warren D
• Format: Article
• Language: English
• Subjects: Adult; African Americans; Alcohol; Amygdala; Anatomy; Biomedical Research; Bipolar disorder; Brain; Brain research; Caudate nucleus; Cerebrum; Community; Comparative analysis; Cultural differences; Data analysis; Data processing; Female; Frontal Lobe - anatomy & histology; Gender differences; Genes; Haplotypes; Health care facilities; Hippocampus; Humans; Information management; Laboratories; Magnetic resonance; Magnetic Resonance Imaging; Male; Medical imaging; Medical research; Medical schools; Mental depression; Mental disorders; Middle Aged; Minority & ethnic groups; Nervous system; Nervous system diseases; Neuroimaging; Neurology; Neuroscience; Neurosciences; NMR; Nuclear magnetic resonance; Nuclei; Patient Selection; Population; Proteins; Psychiatry; Race; Racial differences; Radiology and Medical Imaging/Magnetic Resonance Imaging; Recruiting; Recruitment; Science Policy; Serotonin; Social support; Socioeconomic factors; Temporal Lobe - anatomy & histology; Trends; Ventricle (lateral)
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0013642

Variation in brain structure is both genetically and environmentally influenced. The question about potential differences in brain anatomy across populations of differing race and ethnicity remains a controversial issue. There are few studies specifically examining racial or ethnic differences and also few studies that test for race-related differences in context of other neuropsychiatric research, possibly due to the underrepresentation of ethnic minorities in clinical research. It is within this context that we conducted a secondary data analysis examining volumetric MRI data from healthy participants and compared the volumes of the amygdala, hippocampus, lateral ventricles, caudate nucleus, orbitofrontal cortex (OFC) and total cerebral volume between Caucasian and African-American participants. We discuss the importance of this finding in context of neuroimaging methodology, but also the need for improved recruitment of African Americans in clinical research and its broader implications for a better understanding of the neural basis of neuropsychiatric disorders. This was a case control study in the setting of an academic medical center outpatient service. Participants consisted of 44 Caucasians and 33 ethnic minorities. The following volumetric data were obtained: amygdala, hippocampus, lateral ventricles, caudate nucleus, orbitofrontal cortex (OFC) and total cerebrum. Each participant completed a 1.5 T magnetic resonance imaging (MRI). Our primary finding in analyses of brain subregions was that when compared to Caucasians, African Americans exhibited larger left OFC volumes (F (1,68) = 7.50, p = 0.008). The biological implications of our findings are unclear as we do not know what factors may be contributing to these observed differences. However, this study raises several questions that have important implications for the future of neuropsychiatric research.