Table 4:

Bivariate Pearson correlation coefficients (P values) (n = 29 except as noted)

	Age	Duration^{^a}	EDSS	Flanker^{^b}	Stroop^{^c}
QSM
GP	0.36 (.059)	0.10 (.60)	0.06 (0.75)	0.25 (.20)	−0.18 (.36)
Put	0.57 (.001)^{^f}	0.04 (.85)	0.31 (0.09)	0.3 (.12)	0.01 (.97)
Cau	0.41 (.02)^{^f}	0.42 (.02)^{^f}	0.24 (0.20)	0.47 (.01)^{^f}	0.13 (.50)
Aput	0.55 (.0015)^{^f}	0.05 (.81)	0.30 (0.11)	0.38 (.045)^{^f}	0.00 (.99)
Pput	0.57 (.001)^{^f}	0.09 (.65)	0.35 (0.06)	0.23 (.25)	−0.01 (.94)
R2
GP^{^d}	0.32 (.12)	0.08 (.68)	0.18 (0.38)	0.32 (.11)	0.065 (.76)
Put^{^e}	0.47 (.01)^{^f}	0.09 (.65)	0.43 (0.02)^{^f}	0.31 (.11)	0.21 (.34)
Cau^{^e}	0.37 (.06)	0.29 (.15)	0.58 (.001)^{^f}	0.31 (.11)	0.07 (.75)
Aput^{^e}	0.44 (.02)^{^f}	0.12 (.54)	0.48 (.01)^{^f}	0.35 (.08)	0.17 (.44)
Pput^{^e}	0.47 (.01)^{^f}	0.01 (.96)	0.32 (.04)^{^f}	0.21 (.29)	0.28 (.18)
R2*
GP	0.14 (.45)	−0.23 (.22)	−0.20 (.29)	0.2 (.3)	−0.24 (.22)
Put	0.38 (.047)^{^f}	−0.12 (.51)	0.25 (.19)	0.34 (.075)	−0.02 (.92)
Cau	0.29 (.12)	−0.02 (.90)	0.24 (.20)	0.29 (.13)	0.27 (.17)
Aput	0.30 (.11)	−0.15 (.43)	0.26 (.16)	0.37 (.055)	−0.04 (.84)
Pput	0.45 (.01)^{^f}	−0.06 (.74)	0.17 (.36)	0.23 (.23)	−0.00 (.99)

Note:—Cau indicates caudate; Put, putamen; Aput, cognitive anterior part of putamen, region predominantly connected to frontal cortex; Pput, motor posterior part of putamen, region predominantly connected to sensorimotor cortex.
↵a Using square root transformation for non-normal duration data.
↵b Using square root transformation for non-normal Flanker measure (n = 28).
↵c Stroop measure (n = 27).
↵d For GP R2 n = 27 so that R2–GP versus Flanker (n = 26).
↵e For putamen and caudate R2 n = 28 so that R2–Put, R2–Cau versus Flanker (n = 27).
↵f Statistically significant at P < .05.