title: Development of the brain's structural network efficiency in early adolescence: A longitudinal DTI twin study.
abstract: The brain is a network and our intelligence depends in part on the efficiency of this network. The network of adolescents differs from that of adults suggesting developmental changes. However, whether the network changes over time at the individual level and, if so, how this relates to intelligence, is unresolved in adolescence. In addition, the influence of genetic factors in the developing network is not known. Therefore, in a longitudinal study of 162 healthy adolescent twins and their siblings (mean age at baseline 9.9 [range 9.0-15.0] years), we mapped local and global structural network efficiency of cerebral fiber pathways (weighted with mean FA and streamline count) and assessed intelligence over a three-year interval. We find that the efficiency of the brain's structural network is highly heritable (locally up to 74%). FA-based local and global efficiency increases during early adolescence. Streamline count based local efficiency both increases and decreases, and global efficiency reorganizes to a net decrease. Local FA-based efficiency was correlated to IQ. Moreover, increases in FA-based network efficiency (global and local) and decreases in streamline count based local efficiency are related to increases in intellectual functioning. Individual changes in intelligence and local FA-based efficiency appear to go hand in hand in frontal and temporal areas. More widespread local decreases in streamline count based efficiency (frontal cingulate and occipital) are correlated with increases in intelligence. We conclude that the teenage brain is a network in progress in which individual differences in maturation relate to level of intellectual functioning.
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Marinka M G
authors.initials: MM
authors.lastname: Koenis
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Rachel M
authors.initials: RM
authors.lastname: Brouwer
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Martijn P
authors.initials: MP
authors.lastname: van den Heuvel
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: René C W
authors.initials: RC
authors.lastname: Mandl
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.|Department of Biological Psychology, VU University, Amsterdam, The Netherlands.
authors.forename: Inge L C
authors.initials: IL
authors.lastname: van Soelen
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: René S
authors.initials: RS
authors.lastname: Kahn
authors.affiliation: Department of Biological Psychology, VU University, Amsterdam, The Netherlands.
authors.forename: Dorret I
authors.initials: DI
authors.lastname: Boomsma
authors.affiliation: Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, The Netherlands.
authors.forename: Hilleke E
authors.initials: HE
authors.lastname: Hulshoff Pol
mesh_terms: D000293:Adolescent; D001921:Brain / Q000033:anatomy & histology* / Q000254:growth & development*; D001931:Brain Mapping; D002648:Child; D003071:Cognition / Q000502:physiology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007360:Intelligence / Q000235:genetics; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D016571:Neural Networks, Computer; D009434:Neural Pathways / Q000254:growth & development*; D014427:Twins
keywords: DTI; adolescence; brain; development; graph theory; heritability; intelligence; longitudinal; network