Nocera JR, Roemmich R, Elrod J, Altmann LJ, Hass CJ. Effects of cognitive task on gait initiation in Parkinson disease: Evidence of motor prioritization? J Rehabil Res Dev. 2013;50(5):699–708.http://dx.doi.org/10.1682/JRRD.2012.06.0114

Figure 1. Mean and standard error values of anticipatory postural adjustments (APA) for healthy young adults (HYA), healthy older adults (HOA), and individuals with Parkinson disease (PD). APA displacement during gait initiation (GI) in (a) anterior-posterior (AP) and (b) medial-lateral (ML) directions. APA velocity during GI in (c) AP and (d) ML directions. Note that PD group demonstrated decreased displacements and velocities when compared with HYA on all four variables (p < 0.05). Additionally, when compared with HOA, PD group demonstrated significantly less displacement in ML direction and significantly less velocity in AP and ML directions of APA during GI (p < 0.05). *Significant at p < 0.05.