title: Reduced Gyrification Is Related to Reduced Interhemispheric Connectivity in Autism Spectrum Disorders.
abstract: OBJECTIVE
  Autism spectrum disorders (ASD) have been associated with atypical cortical gray and subcortical white matter development. Neurodevelopmental theories postulate that a relation between cortical maturation and structural brain connectivity may exist. We therefore investigated the development of gyrification and white matter connectivity and their relationship in individuals with ASD and their typically developing peers.
  
  
  METHODS
  T1- and diffusion-weighted images were acquired from a representative sample of 30 children and adolescents with ASD (aged 8-18 years), and 29 typically developing children matched for age, sex, hand preference, and socioeconomic status. The FreeSurfer suite was used to calculate cortical volume, surface area, and gyrification index. Measures of structural connectivity were estimated using probabilistic tractography and tract-based spatial statistics (TBSS).
  
  
  RESULTS
  Left prefrontal and parietal cortex showed a relative, age-dependent decrease in gyrification index in children and adolescents with ASD compared to typically developing controls. This result was replicated in an age-and IQ-matched sample provided by the Autism Brain Imaging Data Exchange (ABIDE) initiative. Furthermore, tractography and TBSS showed a complementary pattern in which left prefrontal gyrification was negatively related to radial diffusivity in the forceps minor in participants with ASD.
  
  
  CONCLUSIONS
  The present study builds on earlier findings of abnormal gyrification and structural connectivity in the prefrontal cortex in ASD. It provides a more comprehensive neurodevelopmental characterization of ASD, involving interdependent changes in microstructural white and cortical gray matter. The findings of related abnormal patterns of gyrification and white matter connectivity support the notion of the intertwined development of 2 major morphometric domains in ASD.
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands. Electronic address: d.j.bos-2@umcutrecht.nl.
authors.forename: Dienke J
authors.initials: DJ
authors.lastname: Bos
authors.affiliation: Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del area de Salud Mental (CIBERSAM), Madrid.
authors.forename: Jessica
authors.initials: J
authors.lastname: Merchán-Naranjo
authors.affiliation: Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain.
authors.forename: Kenia
authors.initials: K
authors.lastname: Martínez
authors.affiliation: Ciber del area de Salud Mental (CIBERSAM), Madrid; Institute of Psychiatry, King's College London, UK.
authors.forename: Laura
authors.initials: L
authors.lastname: Pina-Camacho
authors.affiliation: Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain.
authors.forename: Ivan
authors.initials: I
authors.lastname: Balsa
authors.affiliation: Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del area de Salud Mental (CIBERSAM), Madrid.
authors.forename: Leticia
authors.initials: L
authors.lastname: Boada
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Hugo
authors.initials: H
authors.lastname: Schnack
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Bob
authors.initials: B
authors.lastname: Oranje
authors.affiliation: Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del area de Salud Mental (CIBERSAM), Madrid; Universidad Carlos III de Madrid.
authors.forename: Manuel
authors.initials: M
authors.lastname: Desco
authors.affiliation: Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del area de Salud Mental (CIBERSAM), Madrid.
authors.forename: Celso
authors.initials: C
authors.lastname: Arango
authors.affiliation: Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del area de Salud Mental (CIBERSAM), Madrid.
authors.forename: Mara
authors.initials: M
authors.lastname: Parellada
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Sarah
authors.initials: S
authors.lastname: Durston
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands; Hospital General Universitario Gregorio Marañón, School of Medicine, Universidad Complutense, Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain; Ciber del area de Salud Mental (CIBERSAM), Madrid.
authors.forename: Joost
authors.initials: J
authors.lastname: Janssen
mesh_terms: D000293:Adolescent; D000067877:Autism Spectrum Disorder / Q000473:pathology* / Q000503:physiopathology; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology; D002648:Child; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008297:Male; D009434:Neural Pathways / Q000473:pathology / Q000503:physiopathology; D059906:Neuroimaging; D010296:Parietal Lobe / Q000473:pathology / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000473:pathology / Q000503:physiopathology
keywords: autism spectrum disorders; development; forceps minor; gyrification index; structural connectivity