Fig. 6.

Brain regional networks that showed significant differences in age-efficiency correlation between dominant and nondominant hand grip across more than half of the range from 0.10 to 0.40 of connection densities when considering (A) 8 brain regions and (B) 16 brain regions. Red and blue indicate higher and lower age-efficiency correlations respectively for dominant hand grip compared with nondominant hand grip. Abbreviations: C, contralateral; Cbl, cerebellar; Frn, frontal; I, ipsilateral; Lmb, limbic and paralimbic; Occ, occipital; Prt, parietal; SC, subcortical; SM, sensorimotor; Tmp, temporal.