Light touch is the combination of cutaneous and kinesthetic inputs. The literature suggests that light touch compensates for a reduced amount of center of pressure information in older peoples, blind subjects and patients with neurological disorder. This study investigated the effects of light touch applied to an external bar, on the postural sway in individuals with hemiparetic stroke. We used a cross sectional study, fifteen individuals with stroke and 15 healthy age-matched adults stood as still as possible on a force plate. Experimental trials (duration, 30 s) included two visual conditions (open eyes and closed eyes), two somatosensory conditions (no touch and light touch) and two support surface conditions (firm and foam surfaces). The area of center of pressure (COP) and the mean velocity of COP in the medio-lateral and anterior-posterior directions were assessed. For both groups, COP velocity and area decreased with light touch regardless of the visual or surface conditions. The effects of light touch were similar in both groups. In addition, results show that the effectiveness of light touch in reducing postural sway was greater on a foam surface than on a firm surface. Our findings indicate that light touch could be beneficial in postural control for individuals with hemi-paretic stroke.
Keywords: Balance; Light touch; Stroke.