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bioRxiv · 10.1101/2021.02.14.431143

The relationship between dynamic functional network connectivity and spatial orientation in healthy young adults

Sendi, M. S. E.·Ellis, C. A.·Miller, R. L.·Salat, D. H.·Calhoun, V. D.
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Abstract

Spatial orientation is essential to interacting with a physical environment, and better understanding it could contribute to a better understanding of a variety of diseases and disorders that are characterized by deficits in spatial orientation. Many previous studies have focused on the relationship between spatial orientation and individual brain regions, though in recent years studies have begun to examine spatial orientation from a network perspective. This study analyzes dynamic functional network connectivity (dFNC) values extracted from over 800 resting-state fMRI recordings of healthy young adults (age 22-37 years) and applies unsupervised machine learning methods to identify neural brain states that occur across all subjects. We estimated the occupancy rate (OCR) for each subject, which was proportional to the amount of time that they spent in each state, and investigated the link between the OCR and spatial orientation and the state-specific FNC values and spatial orientation controlling for age and sex. Our findings showed that the amount of time subjects spent in a state characterized by increased connectivity within and between visual, auditory, and sensorimotor networks and within the default mode network while at rest corresponded to their performance on tests of spatial orientation. We also found that increased sensorimotor network connectivity in two of the identified states negatively correlated with decreased spatial orientation, further highlighting the relationship between the sensorimotor network and spatial orientation. This study provides insight into how the temporal properties of the functional brain connectivity within and between key brain networks may influence spatial orientation.

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Sendi, M. S. E., Ellis, C. A., Miller, R. L., Salat, D. H., Calhoun, V. D.. 2021-02-16. The relationship between dynamic functional network connectivity and spatial orientation in healthy young adults. https://doi.org/10.1101/2021.02.14.431143

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