A sequential classification of oculomotor deficits in ALS has been suggested [29] and considered to be in line with progression of phosphorylated TAR DNA-binding protein (pTDP-43) pathology from frontal cortex into brainstem areas [32]: antisaccade deficits occur early in the disease course (“stage 1”), followed by additional smooth pursuit dysfunctions and slowing of prosaccades (“stage 2”) [29]. Here, TARDBP is linked to amyotrophic lateral sclerosis.