Juggling revisited — A voxel–based morphometry study with expert jugglers

• Published in: NeuroImage (Orlando, Fla.) Vol. 95; pp. 320 - 325
• Main Authors: Gerber, P., Schlaffke, L., Heba, S., Greenlee, M.W., Schultz, T., Schmidt-Wilcke, T.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 15-07-2014; Elsevier; Elsevier Limited
• Subjects: Adult; Age; Biological and medical sciences; Brain; Brain - anatomy & histology; Brain - physiology; Brain Mapping; Cross-Sectional Studies; Eye and associated structures. Visual pathways and centers. Vision; Female; Fundamental and applied biological sciences. Psychology; Gender; Gray Matter - anatomy & histology; Humans; Image Processing, Computer-Assisted; Intraparietal sulcus; Juggling; Magnetic Resonance Imaging; Male; Motion Perception - physiology; Motor learning; Psychomotor Performance - physiology; Studies; Vertebrates: nervous system and sense organs; Visual cortex; Visual Perception - physiology; Voxel based morphometry; Young Adult; VBM; svc; PPC; Visual cortex; Intraparietal sulcus; BDNF; GM; MT; IPS; Motor learning; sc; Juggling; Voxel based morphometry; WM; DTI; FA; BA; Visual pathway; Central nervous system; Morphometry; Encephalon
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2014.04.023

Juggling is a highly interesting tool to investigate neuroplasticity associated with motor-learning. Several brain-imaging studies have reported changes in regional brain morphology in visual association cortices in individuals learning how to juggle a three-ball cascade. However, to our knowledge there are no studies that investigated expert jugglers, looking for specific features in regional brain morphology related to this highly specialized skill.
Using T1-weighted images and voxel-based morphometry we investigated in a cross-sectional study design 16 expert jugglers, able to juggle at least five balls and an age- and gender-matched group of non-jugglers. We hypothesized that expert jugglers would show higher gray matter density in regions involved in visual motion perception and eye-hand coordination. Images were pre-processed and analyzed using SPM8. Age was included in the analyses as covariate of no interest.
As compared to controls jugglers displayed several clusters of higher, regional gray matter density in the occipital and parietal lobes including the secondary visual cortex, the hMT+/V5 area bilaterally and the intraparietal sulcus bilaterally. Within the jugglers group we also found a correlation between performance and regional gray matter density in the right hMT+/V5 area.
Our study provides evidence that expert jugglers show increased gray matter density in brain regions involved in visual motion perception and eye–hand coordination, i.e. brain areas that have previously been shown to undergo dynamic changes in terms of gray matter increases in subjects learning a basic three-ball cascade. The extent to which transient increases in beginners and the differences in experts and non-experts are based on the same neurobiological correlates remains to be fully elucidated.
•Using voxel based morphometry we investigated expert jugglers and non-jugglers.•Jugglers displayed higher levels of gray matter density in the visual system.•Gray matter density in the right hMT+/V5 region correlated with performance.