FIG4 and amyotrophic lateral sclerosis: Two additional cases of I41T heterozygous patients have been reported with an aggressive form of ALS and typical bilateral corticospinal tract hyperintensities in T2/FLAIR sequences, as well as bilateral “motor band sign” on brain MRI [21,22] No ALS patient with either the I41T or alternative FIG4 mutations has ever been reported to manifest parkinsonian symptoms.