Timing of reactive stepping among individuals with sub-acute stroke: effects of ‘single-task’ and ‘dual-task’ conditions

Abstract

Performance decrements in balance tasks are often observed when a secondary cognitive task is performed simultaneously. This study aimed to determine whether increased cognitive load resulted in altered reactive stepping in individuals with sub-acute stroke, compared to a reactive stepping trial with no secondary task. The secondary purpose was to determine whether differences existed between the first usual-response trial, subsequent usual-response trials, and the dual-task condition. Individuals with sub-acute stroke were exposed to external perturbations to elicit reactive steps. Perturbations were performed under a usual-response (single-task) and dual-task condition. Measures of step timing and number of steps were based on force plate and video data, respectively; these measures were compared between the usual-response and dual-task trials, and between the first usual-response trial, later usual-response trials (trials 2–5) and a dual-task trial. A longer time of unloading onset and greater number of steps were identified for the first usual-response trial compared to later usual-response trials. No significant differences were identified between usual-response and dual-task trials. Although improvements were observed from the first to subsequent usual-response lean-and-release trials, performance then tended to decrease with the introduction of the dual-task condition. These findings suggest that when introduced after usual-response trials, the dual-task trial may represent the first trial of a new condition, which may be beneficial in reducing the potential for adaptation that may occur after multiple repetitions of a reactive stepping task. Therefore, these findings may lend support to the introduction of a new condition (i.e. a dual-task trial) in addition to usual-response trials when assessing reactive balance in individuals with stroke.

Backward Protective Stepping During Dual-Task Scenarios in People With Parkinson’s Disease: A Pilot Study

“…[24][25][26][27] Interestingly, however, when larger-magnitude perturbations are used, the resulting protective step is not consistently impacted by a secondary dual task. 12,28,29 For example, 2 studies, 12,28 showed little to no impact of a secondary task on step outcomes in stroke survivors and age-matched controls, respectively. Zettel et al 29 showed that in older adults, only mediolateral anticipatory postural responses prior to the protective step was affected by dual tasking.…”

Use of Functional Balance Measurement Tools to Predict the Fear of Falling in Faller and Non-Faller Chronic Stroke Patients

“…The stroke patients with FOF avoid different activities which may lead to restricted mobility, reduced functional capabilities, and loss of functional independence. It is noteworthy that this avoidance leads to the muscle atrophy and weakens the balance performance which finally increases the risk of falling and FOF (Schinkel-Ivy, Inness, & Mansfield, 2016). Various studies among stroke population have shown that the severity of disease, the balance impairment, and the FOF may be related to the lower physical activity levels (Goh, Nadarajah, Hamzah, Varadan, & Tan, 2016;Rosén, Sunnerhagen, & Kreuter, 2005;Shaikh & asghar Hosseini, 2016).…”