208 13. Neuroimaging, Structural the Schedule for the Deficit Syndrome criteria, and 5 patients with apathy developed after TBI(4 males, 1 female, mean age 42). All subjects were screened with the SCID and were administered SAPS/SANS and the Apathy Evaluation Scale. Basal ganglia vol- ume measures were obtained according to previously published data (Arch. Gen. Psychiatry, 1996, 577-84). Total brain volume (TBV) and age were used as covariates. TBV did not differ between groups. Analysis of covariance showed no statistical significant differences between the two diagnostic groups for the caudate (left and right: p=.20 and p=. 19, respectively) and putamen (left and right: p=.82 and p=.79, respectively). These preliminary results seem to suggest that the basal ganglia are not differentially affected in the two groups of patients studied who differ for their clinical diagnosis but who share a similar phenomenology (i.e. negative symptoms). We plan to present results from a larger sample of patients as well as from controls of non-deficit schizophrenia and normals. AGE AND TREATMENT RELATED LOCAL HIPPOCAMPAL CHANGES IN SCHIZOPHRENIA EXPLAINED BY A NOVEL SHAPE ANALYSIS METHOD M. Styner,* G. Gerig, E. Kistner, K. Muller, J. Lieberman Computer Science, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA Volume reduction of the hippocampus observed with MRI is one of the most consistently described structural abnormalities in patients with schizophrenia. However, the timing, the association with treat- ment, and an intuitive explanation of morphologic changes are not known. This study analyzed subtle changes of the hippocampal struc- ture in schizophrenics (N=57) as compared to matched controls (N=26). The effect of age, duration of illness and drug type to local shape changes was studied with a new shape representation tech- nique and an exploratory statistical analysis. Individual hippocam- pal objects were aligned with respect to their intrinsic coordinate frame to eliminate shape effects caused by variation of object pose. Shape representation was based on a sampled medial model describ- ing each shape by an 8 by 3 mesh with local position and width at each node. This model allows a separate analysis of shape deforma- tion and of local atrophy. The exploratory statistical model was a repeated measures ANOVA, cast as a general linear multivariate model. The statistical model for deformation included age, drug (yes, no), and age x drug as predictors, with distance averaged across side of the hippocampus' (left/right) as the outcome of interest (p = 0.0097). The difference in hippocampus shape between patients and controls is located mostly in the tail, and becomes more pronounced over time. The statistical model for analysis of local atrophy includ- ed age, drug type (none, typical, atypical), the interaction of age x drug (yes, no), and the interaction of duration x drug (yes, no) as pre- dictors, with the difference of distance between side (left - right) of the hippocampus as the outcome of interest (p = 0.0077). Points at the head and tail of the object, not the center, show differences. Giv- en the expected atrophy over time due to aging, it seems that the hip- pocampus of a young schizophrenic looks like the hippocampus of an older control, and the two groups look more alike later in time. Furthermore, the atypical treated patients start (at an early age) less far from the nonnals than do those treated with typical drugs. The exploratory nature of the analysis means that these promising results must be replicated in order to provide full confidence in the conclu- sions. PROGRESSIVE FRONTAL LOBE REDUCTION 1N FIRST EPISODE PSYCHOSIS D. Sun,* G. W. Stuart, S. J. Wood, D. Velakoulis, M. Yficel, E D. McGorry, C. Pantelis Psychiatry, The University of Melbourne, Melbourne, VIC, Australia Previous longitudinal research using MRI scans has shown whole- brain volume loss in first-episode psychosis (FEP) and chronic schiz- ophrenia (CS) compared to normal subjects. In this study, a novel MRI image analysis method was used to measure the longitudinal brain surface motion, as a parameter of volumetric change, and to localize the change to various brain regions. Subjects with first episode psy- chosis (n=24), with chronic schizophrenia (n= 11) and control subject (n=29) were recruited in this study, with 2 follow-up high-resolution head MRI images scanned, on average 2 years apart (FEP: 2.02 +/- 0.75 yrs; CS: 2.44 +/- 0.98 yrs; Controls 2. l 6 +/- 0.96 yrs). The whole brain reduction of the FEP group was significantly greater than that of normal controls. Regional anaiysis showed that brain reduction in frontal areas mainly accounted for the whole brain change, with signi- ficant reduction in both left and right dorsolateral frontal surface. No significant difference was found in the occipital or temporal lobes, or for lateral and third ventricles. There was no significant difference between CS and controls in any brain area. Frontal areas are consid- ered to be highly involved in the clinical symptoms and cognitive impairments of" psychosis and schizophrenia. This follow-up study showed more brain tissue loss in this area in first episode psychosis, indicating that besides well-known pre-existing structural brain abnor- malities, progressive brain structural change beyond the onset of ill- ness in crucial brain regions is a probable characteristic of psychosis. SEX DIFFERENCES IN FRONTAL LOBE WHITE MATTER INTEGRITY IN HEALTHY HUMANS: A DIFFUSION TENSOR IMAGING STUDY R R. Szeszko,* J. Vogel, M. Ashtari, T. Frevert, A. Malhotra, J. Kane, R. Bilder, K. Lim Department of Psychiatry Research, The Zucker Hillside Hospital, Glen Oaks, NY, USA There is little empirical data from brain imaging studies regarding possible sex differences in the white matter microstructure of the brain. Diffusion tensor imaging (DTI) represents an in-vivo tech- nique for quantifying the directionality and coherence of white mat- ter fibers. In this preliminary study 11 healthy male and 14 healthy female subjects completed diffusion tensor imaging exams to inves- tigate possible sex differences in frontal lobe white matter integrity. Eighteen axial DTI (slice thickness = 5mm) were acquired through the whole head parallel to the AC-PC plane on a 1.5T Echo Speed GE LX magnetic resonance imaging system. Diffusion was measured along six nonlinear directions (Gx, Gy, Gz) = {(1,1,0), (1,0,1), (0,1,1), (1,-1,0), (-l,0,1), (0,1,-1)} and an acquisition without difth- sion weighting (b = 0) was also acquired. Six maps of the apparent diffusion coefficient were computed, from which the diffusion ten- sor was calculated. From this tensor, eigenvalues and eigenvectors were derived and fractional anisotropy (FA) was computed from these measm'es for each voxel. The frontal white matter regions-of- interest were obtained in each hemisphere at seven different slice levels: 5mm below the AC, at the AC, and 5ram through 25ram above the AC. Analyses consisted of a repeated measures ANCOVA for each slice with sex as a between subjects factor, hemisphere as a within subjects factor and age as a covariate. Findings indicated significant (p < .05) sex-by-hemisphere interactions on the slices International Congress on Schizophrenia Research 2003