The Effects of Practice on the Concurrent Performance of a Speech and Postural Task in Persons with Parkinson Disease and Healthy Controls
Table 2
Values (SD) for each postural control measure at acquisition and retention phases for each group.
Acquisition (baseline)
Acquisition (ending)
Retention 48 hrs
Retention 1 week
Block 1
Block 7
Block 1
Block 1
mean (SD)
mean (SD)
mean (SD)
mean (SD)
Reaction time (sec)
HY group
0.66 (0.16)
0.59 (0.14)
0.61 (0.10)
0.67 (0.11)
AM group
0.76 (0.21)
0.74 (0.36)
0.70 (0.25)
0.75 (0.29)
PD group
0.79 (0.20)
0.67 (0.36)
0.78 (0.22)
0.73 (0.10)
COP Vel (mm/sec)
HY group
381.39 (166.64)*,#
473.26 (146.95)
446.85 (179.12)
503.16 (217.22)
AM group
263.30 (184.21)
227.08 (227.76)
331.05 (301.86)
238.58 (229.46)
PD group
97.13 (261.83)
113.45 (235.31)
108.02 (219.66)
139.39 (219.58)
COP_COM diff (mm)
HY group
52.84 (21.69)*
62.74 (26.56)
59.97 (24.40)
62.65 (22.95)
AM group
41.18 (26.45)
40.58 (9.75)
44.88 (19.60)
43.73 (14.40)
PD group
18.43 (25.80)
23.40 (23.15)
27.72 (21.49)
31.23 (26.52)
Heel Height CV (%)
HY group
3.86 (2.50)*,**
2.79 (4.10)
2.58 (1.70)
2.07 (3.30)
AM group
2.43 (4.70)
3.72 (8.80)
3.01 (22.50)
2.18 (13.80)
PD group
14.35 (5.08)
24.74 (43.30)
13.59 (43.90)
9.03 (27.50)
HY group: healthy young adult controls; AM group: healthy age-matched controls; PD group: persons with PD. All values: median (interquartile range). Significant difference between groups. Significant difference between acquisition block 1 (baseline) and block 1 at 48 hr retention and block 1 at 1 wk retention. Significant difference between acquisition block 1 and 7.