[Cognitive development of normal school age children: a resting-state fMRI study]

To investigate the characteristics of cognitive development in elementary school children using rest-fMRI methods.

Twenty-nine normal school children were divided into three groups according to their ages (8, 10 & 12 years old) and received the resting-state fMRI scans. A regional homogeneity (ReHo) approach was used to analyze blood oxygen level-dependent fMRI (BOLD-fMRI) data in resting state. The fMRI data were processed with software SPM2 and REST 1.2.

Compared with younger groups (10 vs 8, 12 vs 10, 12 vs 8), the elder groups showed more increases in superior temporal gyrus (Z = 2.83, Z = 3.21), middle temporal gyrus (Z = 3.74, Z = 3.19, Z = 4.26), inferior temporal gyrus (Z = 3.01) and lentiform nucleus (Z = 3.31). In addition, the ReHo differences were demonstrated in superior frontal gyrus (Z = 3.21), middle frontal gyrus (Z = 3.19, Z = 3.22), medial frontal gyrus (Z = 3.15), lingual gyrus (Z = 3.43) and cerebellum (Z = 3.11, Z = 2.97) increased more in 12 years old group (12 vs 10, 12 vs 8). And the precuneus (Z = 2.95) and posterior cingulate (Z = 2.64) had increasing ReHo values with the age growth (12 vs 8).

The function of execution control, accommodation of attention, visual spatial integration and default mode network became gradually developed with increasing age.