The sequence effect is a validated measure of PD motor disability
dystonia, PD motor disability, PD, bradykinesia, Huntington’s disease, PSP
DYSTONIA, MULTIPLE SYSTEM ATROPHY, DISEASE, PROGRESSIVE SUPRANUCLEAR PALSY
In this study the sequence effect was significantly correlated with overall PD motor disability (MDS-UPDRS III), and this was not solely due to lower angular velocities in later stages of disease, as it was normalized by initial peak velocity. The sequence effect was also significantly correlated with the lateralized bradykinesia sub-score on the MDS-UPDRS III; this is expected as bradykinesia is defined as “slowness of movement and decrement in amplitude or speed (sequence effect) as movements are continued”, which is similar to its definition in the first formal diagnostic criteria for PD [Previous literature suggests that the sequence effect appears to be specific to PD and multiple system atrophy but does not appear to be a major feature of progressive supranuclear palsy (PSP), Huntington’s disease, or dystonia [