Objective:To explore the differences in the standardized z-score amplitude of low-frequency fluctuations (zALFFs) across different brain regions between children with global developmental delay (GDD) and healthy children (HC) using functional near-infrared spectroscopy (fNIRS), and correlating zALFF values with the subjects′ Gesell Developmental Scale (GDS) scores.Methods:Thirty-one children aged 2-4 years with GDD and 29 HC of the same age were studied. fNIRS was used to record both groups′ brain activity in response to natural stimuli and to measure any changes in oxygenated hemoglobin (HbO) levels in cerebral blood flow. zALFF values were calculated and the values of 44 channels were compared between the two groups. The correlations between zALFF values and GDS scores were computed.Results:The zALFF values of the children with GDD were significantly lower than those of the HC in the right frontal pole (channel 10) and the right pre-motor and supplementary motor areas (channel 43). In contrast, the zALFF values in the left pre-motor and supplementary motor areas (channels 24 and 26) were significantly higher in the children with GDD compared to the HC. Spearman ranked correlation analysis revealed that the zALFF values in the right pre-motor and supplementary motor areas (channel 43) were positively correlated with socialization scores on the GDS ( r=0.37, P≤0.05). Conclusions:The delays in cognitive and motor development in children with GDD may be associated with functional abnormalities in the right frontal polar region and the bilateral premotor and supplementary motor areas. zALFF values from the right premotor and supplementary motor areas are positively correlated with social skills.

Objective:To explore the differences in the standardized z-score amplitude of low-frequency fluctuations (zALFFs) across different brain regions between children with global developmental delay (GDD) and healthy children (HC) using functional near-infrared spectroscopy (fNIRS), and correlating zALFF values with the subjects′ Gesell Developmental Scale (GDS) scores.Methods:Thirty-one children aged 2-4 years with GDD and 29 HC of the same age were studied. fNIRS was used to record both groups′ brain activity in response to natural stimuli and to measure any changes in oxygenated hemoglobin (HbO) levels in cerebral blood flow. zALFF values were calculated and the values of 44 channels were compared between the two groups. The correlations between zALFF values and GDS scores were computed.Results:The zALFF values of the children with GDD were significantly lower than those of the HC in the right frontal pole (channel 10) and the right pre-motor and supplementary motor areas (channel 43). In contrast, the zALFF values in the left pre-motor and supplementary motor areas (channels 24 and 26) were significantly higher in the children with GDD compared to the HC. Spearman ranked correlation analysis revealed that the zALFF values in the right pre-motor and supplementary motor areas (channel 43) were positively correlated with socialization scores on the GDS ( r=0.37, P≤0.05). Conclusions:The delays in cognitive and motor development in children with GDD may be associated with functional abnormalities in the right frontal polar region and the bilateral premotor and supplementary motor areas. zALFF values from the right premotor and supplementary motor areas are positively correlated with social skills.