AIF1 and amyotrophic lateral sclerosis: Both C9‐ALS subgroups (language‐impaired and language‐unimpaired) had more CD68+ superpixels per Iba1+ superpixel in BA39, suggestive of elevated microglial activation in C9‐ALS, with significant differences in y‐intercepts of linear models (language‐impaired: y = 7.482, p < 0.001; language‐unimpaired: y = 4.1073, p < 0.05) compared to controls (y = 3.878) (Figure 6C).