Figure 2.

For networks within the small-world range (T = 0.45, T = 0.50), the normalized characteristic path length λ was found to be negatively correlated with IQ, as shown in a and b [linear regression, df = 18; T = 0.45, r = −0.54, p = 0.010 (a); T = 0.5, r = −0.57, p = 0.017 (b), corrected for age]. IQ was not significantly associated with the normalized clustering coefficient γ (c and d for T = 0.45 and T = 0.5 respectively, corrected for age). The negative association between λ and IQ suggests a strong positive association between the level of global communication efficiency within the brain network and intelligence.