Thalamic Nuclei Morphometry and Handedness: Assessing Grey Matter Volume Differences in Left- and Right-Dominant Individuals

The connection between thalamic structure and handedness has important implications for understanding the neural basis of lateralization, and this may shed light on the underlying mechanisms of motor control and cognitive processes. This study investigated the relationship between thalamic nuclei morphometry and handedness, aiming to elucidate the neuroanatomical basis of manual preference. Utilising neuroimaging data from a test-retest functional magnetic resonance imaging (MRI) dataset, T1-weighted volumes were acquired and processed using automated segmentation methods. Thalamic nuclei were parcellated into 25 regions, and grey matter volumes were analysed using the Freesurfer software tool. Statistical comparisons of the interhemispheric volume of the four thalamic nuclei between left- and right-dominant individuals were conducted using independent sample t-tests. This study identified interhemispheric differences in specific thalamic nuclei (the ventral anterior thalamic nucleus and the ventral posterolateral thalamic nuclei) in the left- and rig mht-dominant individuals, suggesting structural variability within the thalamus associated with handedness. The findings underscore the importance of considering subcortical structures in understanding the neural basis of manual preference and highlight avenues for further research in thalamic morphology and its relationship with handedness