Publications by authors named "Amy M Hellman"

Background: Healthy gait dynamics are characterized by the presence of fractal, persistent stride-to-stride variations, which become more random with Parkinson's disease (PD). Rhythmic auditory stimulation with fractal beat-to-beat variations can change gait dynamics in people with PD toward more persistence.

Research Question: How does gait in people with PD change when synchronizing steps with fractal melodic metronomes with different step-to-beat ratios, and which stimulus do they prefer?

Methods: In this cross-sectional study, 15 people with PD and 15 healthy older adults walked over-ground in three conditions: self-paced, paced by a fractal auditory stimulus with a 1:1 step-to-beat ratio ('metronome'), and fractal auditory stimulus with a 1:2 step-to-beat ratio ('music').

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Background: Lightheadedness on standing is a disabling symptom in Parkinson's disease associated with orthostatic hypotension and is thought to represent cardiovascular autonomic dysfunction. Traditional orthostatic blood pressures are normal in some patients with lightheadedness and other measures of cardiovascular dysautonomia can be insensitive. In this study, we used continuous non-invasive arterial pressure monitoring to measure beat-to-beat changes in blood pressure and heart rate on standing and during Valsalva as a potential marker of autonomic dysfunction.

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