Functional connectivity changes across the whole brain in newborns and children

1716 

Abstract Submission 

Yali Huang¹, Xiaoxu Na¹, Xiawei Ou^1,2

¹1. Department of Radiology, University of Arkansas for Medical Sciences, LITTLE ROCK, AR, ²2. Department of Pediatrics, University of Arkansas for Medical Sciences, LITTLE ROCK, AR

Yali Huang  
1. Department of Radiology, University of Arkansas for Medical Sciences
LITTLE ROCK, AR

Xiaoxu Na  
1. Department of Radiology, University of Arkansas for Medical Sciences
LITTLE ROCK, AR

Xiawei Ou  
1. Department of Radiology, University of Arkansas for Medical Sciences|2. Department of Pediatrics, University of Arkansas for Medical Sciences
LITTLE ROCK, AR|LITTLE ROCK, AR

Functional magnetic resonance imaging (fMRI) has been widely used to depicts neural activity in the brain and understand the human brain function. Functional connectivity (FC) is defined as the temporal correlation between brain areas, and it undergoes complex transformation through the life span. Previous studies have shown that functional brain networks undergo a progressive change from isolated local regions to distributed networks until adolescence in the gray matter (Edde et al. 2021). However, such changes in white matter functional connectivity remain unknown. Here, we investigated and explored the differences in white matter brain functional connectivity between infants and 8-year-old children, offering new insights into the development of brain networks. We also compared that with the development of gray matter functional connectivity in these cohorts.

Three set of fMRI data were divided into 16 independent components using the GIFT, respectively (Calhoun et al. 2001, Allen et al. 2014). These 16 components were then defined as 16 functional networks. Subsequently, we performed an in-depth analysis of functional connectivity, exploring both intra-network and inter-network connections within these 16 identified functional networks.
Intra-network FC: For each functional network, we assessed intra-network FC by computing the mean Pearson correlation coefficient across the voxel time courses within the network, excluding diagonal elements. This computation yields 16 intra-network FC metrics per participant, corresponding to the identified functional networks. We further average these metrics across participants within each dataset, obtaining 16 mean intra-network FC values for Newborn group 1 (N=40), Newborn group 2 (N=107), and the 8-year-old children's group (N=43) respectively.
Inter-network FC: For each participant, we compute the inter-network FC by evaluating the Pearson correlation coefficient matrix among all pairs of the 16 functional networks, again omitting diagonal elements. This process provides us with distinct inter-network FC values for each individual and for the group average: N=40 for Newborn group 1, 107 for Newborn group 2, and 43 for the 8-year-old children's group.

Intra-network and inter-network FC within white matter. Fig. 1 displays the results of intra-network and inter-network functional connectivity within white matter across the three datasets. It is evident that intra-network functional connectivity is greater in newborns than in 8-year-old children, whereas inter-network functional connectivity is higher in 8-year-old children compared to newborns. T-tests performed on the inter-network functional connectivity results show no significant differences between the two newborn groups; however, significant differences exist between the 8-year-old children and both newborn groups, with both p-values smaller than 0.001, for both intra- and inter- network FC measures.
Intra-network and inter-network FC within gray matter. Fig. 2 depicts the results of intra-network and inter-network FC within grey matter across the three datasets. Intra-network functional connectivity decreases with age, while inter-network functional connectivity increases with age, similar to the patterns observed in white matter functional networks. T-tests on the inter- and intra- network functional connectivity results reveal no significant differences between the two newborn groups, but significant differences are present between the 8-year-old children and both newborn groups, with both p-values smaller than 0.001, for both intra- and inter- network FC measures.

Our study uncovers a pivotal aspect of neurodevelopment, demonstrating that with brain maturation from infancy to young childhood, there is a marked increase in the connectivity among distinct functional networks, while connectivity within individual networks decreasing. This phenomen is evident not only in grey matter but also in white matter.

Lifespan Development Other ²

fMRI Connectivity and Network Modeling ¹

White Matter Anatomy, Fiber Pathways and Connectivity

BOLD fMRI

Computational Neuroscience

Data analysis

FUNCTIONAL MRI

White Matter

Other - functional connectivity