Obstacle crossing among people with Parkinson disease is influenced

Multitasking situ ations exacerbate g ait im pairments and in crease the ri sk of fallin g among people with Parkinson disease (PD). This study compared obstacle negotiation among 10 sub jects wi th PD an d 10 non parkinsonian co ntrol (CTRL) subjects in tw o test cond itions differentiated by the presence of music played thro ugh a pers onal music player. Subjects walked the len gth o f a 10 m walkway at a selfselected pace, cros sing a 0.15 m obstacle placed at the mid point of the walkway. The results indicated that subjects with PD crossed the obs tacle slower than CTR L subjects and that concurrent music dif ferentially altered obstacle crossing behaviors fo r the CTRL su bjects and subjects with PD. Su bjects with PD further decreased obs tacle-crossing velocitie s and mai ntained spati al paramet ers in the m usic co ndition. In contrast, CTRL subjects maintained all spatiotemporal parameters of obstacle crossing with music. The alterations to crossing behaviors observ ed amo ng th e subjects wi th PD su pport o ur previous suggestion that listening to music while walking may be an attentionally demanding task.