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. DO - 10.3174/ajnr.A2417 AU - B. Alkonyi AU - C. Juhász AU - O. Muzik AU - M.E. Behen AU - J.-W. Jeong AU - H.T. Chugani Y1 - 2011/03/30 UR - http://www.ajnr.org/content/early/2011/03/31/ajnr.A2417.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. ER -