Multimodal MRI analysis of microstructural and functional connectivity brain changes following systematic...

Area of Science:

• Neuroscience
• Cognitive Science
• Medical Imaging

Background:

• Learning new tasks induces rapid microstructural brain changes.
• These changes involve multiple brain regions connected by white matter (WM) tracts.
• Behavioral performance improvements likely result from microstructural, functional, and connectivity changes in neural networks.

Purpose of the Study:

• To investigate the link between learning-induced microstructural changes in WM tracts and functional connectivity.
• To quantify these changes using diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI).
• To explore the potential of virtual reality (VR) for multisensory integration and its impact on brain plasticity.

Main Methods:

• Twenty healthy participants underwent a month of systematic audiovisual (AV) VR training.
• Diffusion Tensor Imaging (DTI) and Diffusion Kurtosis Imaging (DKI) were used to analyze brain microstructural changes.
• Repeated-measures ANOVA and functional connectivity (FC) analysis were employed to assess changes in WM tracts and brain regions.

Main Results:

• A decrease in mean diffusivity (MD) in the SLF II and an increase in fractional anisotropy (FA) in optic radiations were observed post-training and persisted in follow-up.
• Reduced MD significantly correlated with behavioral performance gains.
• Enhanced functional connectivity correlation between primary visual and auditory cortices was evident, supported by DKI findings in relevant brain regions and WM tracts.

Conclusions:

• Multimodal imaging analysis (DTI and DKI) provides complementary evidence of brain network changes.
• Microstructural adaptations in WM tracts are linked to functional connectivity alterations.
• Immersive VR training facilitates multisensory integration, offering potential for learning and rehabilitation strategies.