TY - JOUR T1 - Thalamocortical Connectivity in Healthy Children: Asymmetries and Robust Developmental Changes between Ages 8 and 17 Years JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 962 LP - 969 DO - 10.3174/ajnr.A2417 VL - 32 IS - 5 AU - B. Alkonyi AU - C. Juhász AU - O. Muzik AU - M.E. Behen AU - J.-W. Jeong AU - H.T. Chugani Y1 - 2011/05/01 UR - http://www.ajnr.org/content/32/5/962.abstract N2 - BACKGROUND AND PURPOSE: Thalamocortical connections play a crucial role in complex cognitive functioning, and several neuropsychiatric disorders may involve aberrant thalamocortical circuitry. Here, we quantified the cortical pattern and age-related changes of thalamocortical connections by using probabilistic tractography in children and adolescents. We hypothesized that detectable asymmetry (left>right) exists in thalamocortical fiber connections and the connectivity increases with age during maturation. MATERIALS AND METHODS: Diffusion tensor imaging was acquired in 15 normally developing children (age range, 8.3–17.3 years; 11 males), and fiber tracking was initiated from the thalami. The cortical distribution of ipsilateral thalamocortical fibers was quantified by using a landmark-constrained conformal mapping technique. Furthermore, hemispheric asymmetries and potential age-related changes in regional thalamocortical connections were assessed. RESULTS: The left thalamus had significantly higher overall cortical connectivity than the right thalamus (P < .001). Left prefrontal cortical areas showed significantly higher thalamic connectivity compared with homotopic regions of the right hemisphere (P < .001), regardless of the applied parameters. There was an increase of overall thalamocortical connectivity with age, with the most pronounced age-related increases in bilateral prefrontal areas (P < .002). However, thalamic connectivity of some other cortical regions (right sensorimotor, left inferior temporal) showed a decrease with age. CONCLUSIONS: Our results indicate a region-specific left>right asymmetry and robust developmental changes in thalamocortical (particularly thalamo-prefrontal) connectivity during late childhood and adolescence. These data further add to our knowledge about structural lateralizations and their development in the maturing brain. ADCapparent diffusion coefficientAIasymmetry indexASSETarray spatial sensitivity encoding techniqueDTIdiffusion tensor imagingFAfractional anisotropyFSPGRfast spoiled gradient recalledFTEfinite target elementICBMInternational Consortium for Brain MappingICCintraclass correlation coefficientPDFprobability density functionROIregion of interest ER -