Structural neural basis underlying externalization-internalization transition during adolescence

1291 

Abstract Submission 

Deying Li¹, Haiyan Wang¹, Yufan Wang¹, Congying Chu¹, Lingzhong Fan¹

¹Institute of Automation,Chinese Academy of Sciences, Beijing, China

Deying Li  
Institute of Automation,Chinese Academy of Sciences
Beijing, China

Haiyan Wang  
Institute of Automation,Chinese Academy of Sciences
Beijing, China

Yufan Wang  
Institute of Automation,Chinese Academy of Sciences
Beijing, China

Congying Chu  
Institute of Automation,Chinese Academy of Sciences
Beijing, China

Lingzhong Fan  
Institute of Automation,Chinese Academy of Sciences
Beijing, China

Adolescence, marked by swift neurodevelopment and cognitive-behavioral transformations impacting cognition, personality, and mental health, witnesses problematic behaviors categorized as internalizing or externalizing (Fuhrmann, Knoll et al. 2015, Achenbach, Ivanova et al. 2016), which is correlated with various adverse developmental outcomes. Neuroimaging objectively quantifies developmental changes. Specifically, the geometry of the cerebral cortex and neural connectivity are acknowledged to mutually influence and undergo adaptations during developmental processes(Vasung, Lepage et al. 2016, Wu, Palaniyappan et al. 2023). Comprehending the dynamics of cortical geometry and connectivity changes can yield insights into the emergence of cognitive functions and behaviors(Giedd, Blumenthal et al. 1999). A significant challenge lies in the lack of well-established methodologies for seamlessly integrating cerebral cortex geometry and neural connectivity to comprehensively understand the interplay between brain structure and externalizing/internalizing behaviors in adolescence. This understanding is crucial for determining the optimal timing and nature of interventions. In this study, we propose a novel structural indicator that combines both gray matter and white matter measurements to assess the internalizing and externalizing transition processes during adolescence.

IMAGEN, a large-scale longitudinal neuroimaging cohort study, spanned ages 14, 19, and 22, involving 647 unrelated subjects. T1-weighted images and DWI data underwent preprocessing (Li, Wang et al. 2023) , with subsequent probabilistic tractography mapping the whole-brain anatomical connectivity pattern. We reconstructed 72 tracts identified by TractSeg (Wasserthal, Neher et al. 2018). The fiber connection fingerprint results from projecting each fiber onto the white surface, computed using the LaPy Python library (Pang, Aquino et al. 2023). Geometric modes of the white surface mesh were computed for each age and utilized to reconstruct the fiber connection fingerprint. Reconstruction coefficients were then extracted, forming the novel Fiber Decomposition Index (FDI). Behavioral symptoms in IMAGEN participants were assessed using screening questions from DAWBA and SDQ, covering externalizing and internalizing symptoms(Xie, Xiang et al. 2023). PLSCanonical(PLSC) analysis of FDI with internalizing and externalizing behavioral symptoms was conducted. To avoid overfitting, we implemented a train/test design, assigning 90% to the training set and 10% to the test set. This study specifically focuses on the first principal component, possessing the largest explainable variance.

We examined the explanatory power of geometric eigenmodes for diverse aspects of the white matter fiber connection fingerprint, derived from the white surface mesh at three time points. 200 modes were selected for the study. This decomposition was used to assess the accuracy of geometric eigenmodes in capturing the fiber connection fingerprint in 647 individuals from the IMAGEN dataset. Reconstruction accuracy, measured by vertex-wise Pearson correlation between empirical and reconstructed maps, exceeding a correlation coefficient (r) of 0.80 with 200 modes. The PLSC analysis is conducted on the same participant cohort at both 14y and 19y. A noteworthy relationship is identified between externalizing symptoms with FDI at 14y and internalizing symptoms in 19y.

The geometric foundation of the cerebral cortex aligns well with fiber projection across the cortex. The fitting coefficients exhibit statistically significant associations with both internalizing and externalizing behaviors at ages 14 and 19. Our findings indicate that, at 14y, FDI is significantly linked to externalizing behaviors. Conversely, at 19y, it shows significant associations with internalizing behaviors. This unveils a developmental pattern wherein adolescents transition from externalizing to internalizing behavioral problems.

Normal Brain Development: Fetus to Adolescence ¹

Normal Development ²

Diffusion MRI

Cognition

Cortex

Development

MRI

Structures