C9orf72 and amyotrophic lateral sclerosis: Furthermore, we have shown that PAC is altered at early presymptomatic stages in murine models.21 To explore whether similar PAC changes occur at presymptomatic stages in humans, we are currently conducting a new study involving relatives of familial ALS cases linked to the C9orf72 gene mutation.116 In conclusion, the present groundbreaking study establishes resting-state EEG and PAC analysis as a novel quantitative neuromarker for functional degeneration in ALS, presenting a promising avenue for improving diagnostic accuracy, clinical assessment and therapeutic strategies.