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bioRxiv · 10.1101/2024.02.15.580563

Brain-handedness associations depend on how and when handedness is measured

Tejavibulya, L.·Horien, C.·Fredricks, C.·Ficek-Tani, B.·Westwater, M. L.·Scheinost, D.
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Abstract

Hand preference is ubiquitous, intuitive, and often simplified to right- or left-handed. Accordingly, differences between right- and left-handed individuals in the brain have been established. Nevertheless, considering handedness as a binarized construct fails to capture the variability of brain-handedness associations across different domains or activities. Further, many cultures, environments, and generations impose right-handed norms, and handedness preferences can change over the lifespan. As a result, brain-handedness associations may depend on how and when handedness is measured. We used two large datasets, the Human Connectome Project-Development (HCP-D; n=465; age=5-21 years) and Human Connectome Project-Aging (HCP-A; n=368; age=36-100 years), to explore handedness preferences and brain-handedness associations. Nine items from the Edinburgh Handedness Inventory were associated with resting-state functional connectomes. We show that brain-handedness associations differed across the two cohorts. Moreover, these differences depended on the way handedness was measured. Given that brain-handedness associations differ across handedness measures and datasets, we caution against a one-size-fits-all approach to neuroimaging studies of this complex trait.

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Tejavibulya, L., Horien, C., Fredricks, C., Ficek-Tani, B., Westwater, M. L., Scheinost, D.. 2024-02-15. Brain-handedness associations depend on how and when handedness is measured. https://doi.org/10.1101/2024.02.15.580563

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