Video 1.

First segment: In this video when he is 5 years old, fine motor action elicits tremulous finger movements and intermittent dystonic finger posturing. Age 6, when learning to ride a scooter, he demonstrates reasonable balance and fluidity to pushing without falling. Second segment: During assessment age 9, he has mild tremor at rest but marked distal limb tremor seen with arms held in midline or out in front, as well as intermittent dystonic finger posturing, and added distal hyperkinetic movements of larger amplitude, some which are possibly myoclonic in nature. His gait is relatively fluid and he is able to run and turn with ease, skip, and perform heel and toe walking.