F52. Age-Associated Functional Network Organization in Psychosis Maria Jalbrzikowski 1 , Fuchen Liu 2 , William Foran 1 , Kathryn Roeder 2 , Bernie Devlin 1 , and Beatriz Luna 1 1 University of Pittsburgh, 2 Carnegie Mellon University Background: Psychotic symptoms are believed to result from aberrant integration of information processing between coor- dinated brain networks. It is unknown whether these networks are intact or disrupted during development from adolescence through adulthood in psychosis spectrum youth. Methods: Resting state functional neuroimaging (rsfMRI) data were collected on 678 participants (typically developing¼516; psychosis spectrum¼164, ages 10-25 years) from the Phila- delphia Neurodevelopmental Cohort (PNC) and a longitudinal cohort of typically developing youth (LUNA). We extracted in- dividual time series from an established rsfMRI parcellation and calculated correlations among the parcellation regions. Group averages were calculated in four age groups (late childhood, early adolescence, late adolescence, adulthood). We implemented the Louvain community detection algorithm and a clustering comparison technique, Normalized Mutual Information, to compare identified network organization to the established rsfMRI parcellation. We used jack-knifing and permutation testing to assess stability across four age groups in typically developing youth from the PNC and Luna and psychosis spectrum youth from the PNC. Finally, we compared the stability of network organization between con- trols and psychosis spectrum youth. Results: Network organization was stable across the four age groups in the PNC typically developing youth (all p>0.2), LUNA (all p>.2), and PNC psychosis spectrum youth (all p>0.15). Psychosis spectrum youth had similar functional network or- ganization in comparison to typically developing youth during all developmental stages (all p>0.67). Conclusions: Gross functional network organization is stable in typically developing youth and psychosis spectrum youth. Future analyses will examine to what extent other aspects of connectivity for resting state networks are altered across development. Supported By: R01 MH080243; R21 HD074850; K01 MH112774 Keywords: Adolescence, Brain Networks, Resting State fMRI, Psychosis Spectrum F53. Outward Subcortical Deformations Associated With Sub-Clinical Depression Symptoms in Adolescents Lisanne Jenkins 1 , Jessica Chiang 1 , Kathryn Alpert 2 , Lei Wang 2 , and Gregory Miller 1 1 Northwestern University, 2 Northwestern University Fein- berg School of Medicine Background: Many studies report morphological alterations of subcortical regions in individuals with mood disorders, however inconsistencies in the literature exist, with some reporting increases in volume. These discrepancies are potentially due to age, unrepresentative samples, illness state, medication confounds, or coarse measurements of volume. We undertook a more sensitive shape analysis in a large representative sample of adolescents with subclinical levels of depression. Methods: We conducted FreeSurfer-initiated Large Defor- mation Diffeomorphic Metric Mapping (FS+LDDMM) of subcortical structures using structural 3T MRI in 256 teenagers (mean age¼14) stratified for gender, ethnicity and family so- cioeconomic status (SES). Surfstat implemented in MATLAB regressed morphometric changes on T scores (accounting for gender and grade) from the Depression scale of the Revised Children’s Anxiety and Depression scale (RCADS). Age, gender, Caucasian race, puberty status, intracranial volume and SES were covaried. Multiple comparisons correction was performed using Random Field Theory FWE (p< .05). Results: Depression (M¼46.98, SD¼10.14) scores were pri- marily subclinical (only 3.12% of participants scored above clinical threshold) and did not correlate with volume of any structure. However, higher depression scores predicted more outward shape deformity in the left hippocampus (subiculum and CA1), amygdala, nucleus accumbens, caudate, putamen and thalamus. Conclusions: This is the first study to report regional outward deformity in multiple left hemisphere subcortical structures associated with adolescent’s subclinical depression symp- toms. Consistent with suggestions that subcortical morpho- metric changes in depression are state-dependent; these results may reflect compensatory plasticity. Alternatively, they could reflect accelerated maturation of subcortical structures associated with depression symptoms. Supported By: 1 R01 HL122328 NHLBI/NICHD (PI: Miller) Keywords: Socioeconomic Status, Surface-based Morphometry, Adolescent Depression F54. Methylation of the Dopamine Transporter Gene in Blood is Associated With Striatal Dopamine Transporter Availability in ADHD Corinde Wiers 1 , Falk Lohoff 1 , Jisoo Lee 1 , Christine Muench 1 , Clara Freeman 1 , Amna Zehra 1 , Stefano Marenco 2 , Barbara Lipska 2 , Pavan Auluck 2 , Ningping Feng 2 , Hui Sun 1 , David Goldman 1 , James Swanson 1 , Gene-Jack Wang 1 , and Nora Volkow 1 1 National Institute on Alcohol Abuse & Alcoholism, National Institutes of Health, 2 NIH/NIMH Background: Dopamine transporters (DAT) are implicated in the pathogenesis and treatment of attention deficit hyperac- tivity disorder (ADHD) and are upregulated by chronic treat- ment with methylphenidate, the commonly prescribed medication for ADHD. Methylation of the DAT1 gene in brain and blood has been associated with DAT expression in the brain of rodents. However, the associations in human are still unclear. Methods: We tested the association between methylation of the DAT1 promoter derived from blood and DAT availability in the striatum of unmedicated ADHD adult participants (n¼13) and in that of healthy age-matched controls Poster Abstracts S258 Biological Psychiatry May 1, 2018; 83:S129eS455 www.sobp.org/journal Biological Psychiatry