A MAGNETIC RESONANCE DIFFUSION TENSOR IMAGING STUDY OF THE CINGULATE FASCICULUS IN SCHIZOPHRENIA
Clinical Neuroscience Division, Laboratory of Neuroscience, Department of Psychiatry,
VA Boston Healthcare System, Brockton Division
M. Kubicki, MD, PhD1,2, C.F. Westin, PhD2, R. W. McCarley, MD1, M. Frumin, MD1, P. Nestor, PhD1, R. Kikinis,MD2, F.A. Jolesz, MD2, M.E. Shenton PhD1,2
The aim of this project is to use Magnetic Resonance Diffusion Tensor Imaging (DTI) to evaluate, in vivo, the cingulum bundle in patients diagnosed with chronic schizophrenia, compared with control subjects. Thus rather than quantifying anisotropic diffusion within whole white matter, as in the previous studies in schizophrenia, we will focus on specific white matter tract abnormalities in the cingulum bundle in schizophrenia. According to neuroanatomical observations, the cingulum bundle carries information from other parts of the limbic network, which is later consolidated in the cingulate gyrus, and distributed to the effectory regions of the brain. This particular brain region has figured prominently in post-mortem studies of schizophrenia and is likely relevant to deficits in affectivity, attention, motivation, interpersonal relations, as well as to impaired logical thought, all functions commonly disrupted in schizophrenia.
We will thus examine white matter abnormalities in the cingulum using new DTI techniques. Our Specific aims are:
To test the hypothesis that schizophrenia might, at least in part, be characterized by a disruption of the long interconnecting fibers located within the cingulate fasciculus. We predict that patients diagnosed with schizophrenia will show disruptions in the number and/or density of the cingulum bundle as compared to controls.
To investigate the relationship between anisotropic diffusion abnormalities in the cingulum in schizophrenia and correlate these findings with behavior thought to be relevant to cingulate functioning such as emotional experience, motivation, selective attention, social interactiveness and rational thought processes. We predict that abnormalities in anisotropic diffusion in the cingulate bundle will be associated with alterations in these functions.
To implement a new 3D imaging approach to the data analysis of diffusion images, and to compare this method with our 2D measures, which are more prone to partial volume effects. We hope to show the advantage of the new MR technique for the detection of the white matter tract disruptions in schizophrenia.
Findings from this study will hopefully lead to a better understanding of the role of association fiber tracts, particularly of the cingulum bundle, in schizophrenia, which, in turn, may lead to more informed and targeted treatment based on our increased understanding of the pathophysiology of this devastating disorder.
Grant Support. Support for this work comes from the National Alliance for Research on Schizophrenia and Depression (NARSAD) Young Investigation Award.
Project Sites. Department of Psychiatry, Brain Imaging Laboratory, VA Boston Healthcare System, Brockton Division; Surgical Planning Laboratory and Department of Radiology, Brigham and Women's Hospital, Boston, MA.
Contact Person. Marie Fairbanks, Departmental Administrator. Tel. No. (508) 583-4500, X2479. FAX. (508) 586-0894. E-Mail Address: marie_fairbanks@http://hms.harvard.edu
Representative Publications.
Maier SE, Gudbjartsson H, Patz S, Hsu L, Lovblad KO, Edelman RR, Warach S, Jolesz FA. Line scan diffusion imaging: characterization in healthy subjects and stroke patients. Am J Roentgenol. 1998; 171(1):85-93.
Kubicki M, Westin CF, Maier S, Frumin M, Niznikiewicz M, Nestor PG, Wible CG, Salisbury D, Teh E, Allen C, Berry E, Kikinis R, Jolesz FA, McCarley RA, Shenton ME.Uncinate Fasciculus Findings in Schizophrenia: A Magnetic Resonance Diffusion Tensor Imaging Study. Accepted for publication, AmJPsych.