Video 1. Pretreatment with carbidopa-levodopa neurological examination.Rapid Alternating Movement: • Dysdiadochokinesia is noted with coarse and irregular movement, along with double and triple claps on the palmar and dorsal hand surfaces. Stuttering of movements is also seen. Finger Tap Test: • The patient attempts to perform finger tapping with his index finger and thumb. • A decreased amplitude of finger tapping on the right in comparison with the left with appreciable asymmetry is noticeable in the video. Gait and Turn en Bloc Assessment: • As the video depicts, the patient’s gait shows short steppage with a shuffling pattern and it is unstable as he uses a walker to maintain his stability. • His turn en bloc is also unsteady. In the video, the patient keeps his right foot stationary, and without lifting it, he uses the floor to his advantage to slowly shift his feet on the horizontal plane toward the right. He then uses his left foot to make small pivoting movements, taking at least 6 steps to make a full turn. • After a successful turn, he continues with his shuffling pattern of gait with unsteadiness. Finger-Nose and Past-Pointing Tests: • The patient is first assessed with his eyes open. With his dominant hand, he has noticeable ataxia when stretching his arm and finger as he attempts to make contact with the examiner’s finger. • Upon reaching his target, the patient has dysmetria with overshoot of his finger beyond the examiner’s finger on multiple occasions. • His nondominant hand displays evidence of asymmetry with less ataxia on reaching out toward the target in comparison with his dominant hand, but the dysmetria is consistent with significant overshoot and complete miss of the target, especially at 1 min 47 s. • The patient’s deficits are apparent, especially when he transitions to the eye closure component of the finger-nose and past-pointing assessment, with multiple attempts at reaching the target with complete miss and overshoot. Heel-Knee Test: • As the patient slides his right heel up and down his left shin, he has noticeable side-to-side oscillations representative of a mild degree of cerebellar ataxia. He does not overshoot the knee and does not shoot off his left foot in an uncontrolled manner. • When transitioning to the left heel to shin he has a continuation of side-to-side oscillation but an absence of any overshoot.