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bioRxiv · 10.1101/2021.10.10.463574

Age-related intrinsic functional connectivity changes of locus coeruleus from childhood to older adults

Abstract

The locus coeruleus is critical for selective information processing by modulating brains connectivity configuration. Increasingly studies have suggested that LC controls sensory inputs at the sensory gating stage. Furthermore, accumulating evidence has examined that young children and older adults are more prone to distraction and filter out irrelevant information less efficiently, possibly due to the impaired LC connectivity. However, the LC connectivity pattern across the life span is not fully examined yet, hampering our ability to understand the relationship between LC development and the distractibility. In this study, we examined the intrinsic network connectivity of the LC using resting-state fMRI from the enhanced NKI dataset with wide-range age samples. Based on LC-seed functional connectivity maps, we examined the age-related variation in the LC connectivity with a quadratic model. The analyses revealed two connectivity patterns explicitly. The sensory-related brain regions showed a positive quadratic age effect (u-shape), and the frontal regions for the cognitive control showed a negative quadratic age effect (inverted u-shape). Our results imply that such age-related distractibility is possibly due to the impaired sensory gating by the LC and the insufficient top-down controls by the frontal regions. We discuss the underlying neural mechanisms and limitations of our study.

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BibTeXRIS

Song, I., Neal, J., Lee, T.-H.. 2021-10-12. Age-related intrinsic functional connectivity changes of locus coeruleus from childhood to older adults. https://doi.org/10.1101/2021.10.10.463574

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