SNCA and Parkinson disease: If some aspects of PD specific voice deficits are caused by alpha-synuclein pathology in regions that influence voice and communication, including extra-striatal areas in the brainstem and cortico-bulbar regions, it would explain why voice deficits do not reliably respond to current gold standard therapies that focus on dopamine replacement strategies (Ma et al., 2020; Postuma and Berg, 2016; Seidel et al., 2015).