title: Relative stability of neurocognitive deficits in early onset schizophrenia spectrum patients.
abstract: In contrast to the findings of progressive structural brain changes in adolescence, longitudinal studies of patients with early onset schizophrenia spectrum disorders (EOS) indicate that neurocognitive deficits are relatively stable over the first years. The aim of this study is to assess neurocognitive functions longitudinally in patients with EOS compared to healthy controls (HC) using the MATRICS Cognitive Consensus Battery (MCCB).
  
  
  METHODS
  Twenty patients with EOS and 41 HC were tested with the MCCB at baseline (T1) and after one (T2) and two years (T3). The mean age for the EOS group was 15.6 (SD=1.8) years, while the mean duration of illness was 1.7 (SD=1.4) years at T1.
  
  
  RESULTS
  The EOS group's neurocognitive performances indicate a stable deficit on most measures. Both the EOS and HC groups showed improved neurocognitive functioning over time on all measures except for the verbal learning domain. There was an interaction between the EOS and HC groups' performance over time on the Trail Making Test A (TMA), a subtest on the processing speed domain.
  
  
  CONCLUSIONS
  The longitudinal neurocognitive performances measured by the MCCB confirm previous findings of stable deficits in patients with EOS. It is premature to conclude whether the increases in neurocognitive performance reflect developmental processes in adolescence or may be explained by learning effects, or both. As opposed to the other tests in this domain, a stagnation in processing speed as measured by the TMA suggests that the TMA is a particularly sensitive measure of neurodevelopmental deviance in EOS.
authors.affiliation: Child and Adolescent Mental Health Research Unit, Oslo University Hospital, Box 4959 Nydalen, N-0424 Oslo, Norway. Electronic address: monicaju@psykologi.uio.no.
authors.forename: Monica
authors.initials: M
authors.lastname: Juuhl-Langseth
authors.affiliation: Department of Psychology, University of Oslo, Box 1094 Blindern, N-0317 Oslo, Norway; R&D Department, Mental Health Services, Akershus University Hospital, N-1478 Lorenskog, Norway. Electronic address: a.holmen@psykologi.uio.no.
authors.forename: Aina
authors.initials: A
authors.lastname: Holmén
authors.affiliation: Vestre Viken Hospital Trust, N-1309 Rud, Oslo, Norway. Electronic address: rune.thormodsen@psykologi.uio.no.
authors.forename: Rune
authors.initials: R
authors.lastname: Thormodsen
authors.affiliation: Department of Psychology, University of Oslo, Box 1094 Blindern, N-0317 Oslo, Norway; Division of Mental Health, Innlandet Hospital Trust, N-2629 Lillehammer, Norway. Electronic address: mail@mereteoie.no.
authors.forename: Merete
authors.initials: M
authors.lastname: Oie
authors.affiliation: Department of Psychology, University of Oslo, Box 1094 Blindern, N-0317 Oslo, Norway; Vestre Viken Hospital Trust, N-1309 Rud, Oslo, Norway. Electronic address: b.r.rund@psykologi.uio.no.
authors.forename: Bjørn Rishovd
authors.initials: BR
authors.lastname: Rund
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D003072:Cognition Disorders / Q000503:physiopathology / Q000523:psychology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D011618:Psychotic Disorders / Q000503:physiopathology / Q000523:psychology*; D012559:Schizophrenia / Q000503:physiopathology; D012565:Schizophrenic Psychology
keywords: Early onset schizophrenia; Longitudinal; MCCB; Neurocognition; Processing speed; Trail Making Test A