PVALB and Action tremor: Whereas Lugaro/globular cells are known to be parvalbumin-negative, large glutamatergic DCN neurons surrounded by PNNs may be parvalbumin-positive neurons because it has been reported that parvalbumin-positive large bipolar neurons are present in the DCN (Bastianelli, 2003) and their synaptic dysfunction generates an action tremor (Zhou et al., 2020).