The effects of two different auditory stimuli on functional arm movement in persons with Parkinson's disease: a dual-task paradigm.

OBJECTIVE

To examine, in a dual-task paradigm, the effect of auditory stimuli on people with Parkinson's disease.

DESIGN

A counterbalanced repeated-measures design.

SETTING

A motor control laboratory in a university setting.

SUBJECTS

Twenty individuals with Parkinson's disease. EXPERIMENTAL CONDITIONS: Each participant did two experiments (marching music experiment and weather forecast experiment). In each experiment, the participant performed an upper extremity functional task as the primary task and listened to an auditory stimulus (marching music or weather forecast) as the concurrent task. Each experiment had three conditions: listening to the auditory stimulus, ignoring the auditory stimulus and no auditory stimulus.

MAIN MEASURES

Kinematic variables of arm movement, including movement time, peak velocity, deceleration time and number of movement units.

RESULTS

We found that performances of the participants were similar across the three conditions for the marching music experiment, but were significantly different for the weather forecast experiment. The comparison of condition effects between the two experiments indicated that the effect of weather forecast was (marginally) significantly greater than that of marching music.

CONCLUSIONS

The results suggest that the type of auditory stimulus is important to the degree of interference with upper extremity performance in people with Parkinson's disease. Auditory stimuli that require semantic processing (e.g. weather forecast) may distract attention from the primary task, and thus cause a decline in performance.