Rate of monthly growth change for (a) rostrum, (b) genu, (c) rostral body, (d) anterior midbody, (e) posterior midbody, (f) isthmus, (g) splenium, (h) total corpus callosum.

<p>Positive values indicate increasing size of the area. The point of intersection on the x-axis represents the age of local maximal area. Blue line: males’ LOESS (n = 61), red line: females’ LOESS (n = 53). The arrows show the local maximum for each region calculated using LOESS. For the rostrum, there were local maxima beyond 24 months (2 years) for both females and males, 69 (5.9 years) and 132 months (11 years) old for females and 86 (7.2 years) and 122 months (10.2 years) for males. For the genu, females had two local maxima at 137 (11.5 years) and 214 months (17.1 years), whereas males had only one local maximum at 223 months (18.7 years). For the rostral body, local maxima were observed only in males (55 (4.7 years), 75 (6.3 years), and 233 months (19.5 years)). For the anterior and posterior midbodies, local maxima were observed only once for both sexes (for females at 211 (17.7 years), males at 224 months (18.8 years); for females at 243 (20.3years), males at 209 months (17.5 years), respectively). For the isthmus, splenium and entire corpus callosum, single local maxima were observed only for males (219 (18.3 years), 212 (17.8 years) and 226 months (18.1 years), respectively).