Fig. 1.

Cortical thickness of the precentral gyrus. Mean cortical thickness of the precentral gyrus bilaterally are plotted per study group (healthy controls and patients with ALS, PUMN and ALS-mimic disorders). The dashed horizontal line indicates the mean cortical thickness minus 2 standard deviations of the healthy control group. Cortical thickness measures are in mm. *p < 0.05, **p < 0.001 (ANOVA model followed by pair-wise comparisons, false-discovery rate-corrected for multiple comparisons and adjusted for subject's age). Abbreviations: ALS = amyotrophic lateral sclerosis; HC = healthy controls; PUMN = predominantly upper motor neuron.