title: White matter development in adolescence: diffusion tensor imaging and meta-analytic results.
abstract: BACKGROUND
  In light of the evidence for brain white matter (WM) abnormalities in schizophrenia, study of normal WM maturation in adolescence may provide critical insights relevant to the neurodevelopment of the disorder. Voxel-wise diffusion tensor imaging (DTI) studies have consistently demonstrated increases in fractional anisotropy (FA), a putative measure of WM integrity, from childhood into adolescence. However, the WM tracts that show FA increases have been variable across studies. Here, we aimed to assess which WM tracts show the most pronounced changes across adolescence.
  
  
  METHODS
  DTI was performed in 78 healthy subjects aged 8-21 years, and voxel-wise analysis conducted using tract-based spatial statistics (TBSS). In addition, we performed the first meta-analysis of TBSS studies on WM development in adolescence.
  
  
  RESULTS
  In our sample, we observed bilateral increases in FA with age, which were most significant in the left superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and anterior thalamic radiation. These findings were confirmed by the meta-analysis, and FA increase in the bilateral SLF was the most consistent finding across studies. Moreover, in our sample, FA of the bilateral SLF showed a positive association with verbal working memory performance and partially mediated increases in verbal fluency as a function of increasing age.
  
  
  CONCLUSIONS
  These data highlight increasing connectivity in the SLF during adolescence. In light of evidence for compromised SLF integrity in high-risk and first-episode patients, these data suggest that abnormal maturation of the SLF during adolescence may be a key target in the neurodevelopment of schizophrenia.
authors.affiliation: Division of Psychiatry Research, Zucker Hillside Hospital, Glen Oaks, NY, USA. BPeters1@NSHS.edu
authors.forename: Bart D
authors.initials: BD
authors.lastname: Peters
authors.forename: Philip R
authors.initials: PR
authors.lastname: Szeszko
authors.forename: Joaquim
authors.initials: J
authors.lastname: Radua
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Ikuta
authors.forename: Patricia
authors.initials: P
authors.lastname: Gruner
authors.forename: Pamela
authors.initials: P
authors.lastname: DeRosse
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Zhang
authors.forename: Antonio
authors.initials: A
authors.lastname: Giorgio
authors.forename: Deqiang
authors.initials: D
authors.lastname: Qiu
authors.forename: Susan F
authors.initials: SF
authors.lastname: Tapert
authors.forename: Jens
authors.initials: J
authors.lastname: Brauer
authors.forename: Miya R
authors.initials: MR
authors.lastname: Asato
authors.forename: P L
authors.initials: PL
authors.lastname: Khong
authors.forename: Anthony C
authors.initials: AC
authors.lastname: James
authors.forename: Juan A
authors.initials: JA
authors.lastname: Gallego
authors.forename: Anil K
authors.initials: AK
authors.lastname: Malhotra
mesh_terms: D000293:Adolescent; D041923:Adolescent Development; D016880:Anisotropy; D001921:Brain / Q000254:growth & development* / Q000502:physiology; D002648:Child; D056324:Diffusion Tensor Imaging; D005260:Female; D005625:Frontal Lobe; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D009413:Nerve Fibers, Myelinated; D009434:Neural Pathways / Q000254:growth & development / Q000502:physiology; D009483:Neuropsychological Tests; D009778:Occipital Lobe; D055815:Young Adult