Visual Dependence and Multisensory Balance Rehabilitation After Stroke

Perceived visual dependence will be assessed using a computerized Rod and Disc Test (RDT). Participants will adjust a tilted rod to their subjective visual vertical with rotating visual background. The error (degrees) between subjective visual vertical and gravitational vertical will be measured and represented as the level of visual dependence. Higher error indicates higher level of perceived visual dependence.

Postural sway will be measured using an accelerometer attached on the lower back when participants are looking at blank wall, eyes closed and looking at rotating visual background. Greater postural sway in conditions with eyes closed and rotating visual background corresponding to looking at blank wall represents the higher level of postural visual dependence.

Any falls in the past year (n). Fall is defined by the inadvertently coming to rest on the ground, floor or other lower level, excluding intentional change in position to rest in furniture, wall or other objects. More than once fall is identified as faller.

Physical impairment of paretic leg and foot will be assessed by the Chedoke-McMaster Stroke Assessment (CMSA) with scoring on a 7-point scale (Stage 1 through 7, most impairment through to no impairment, respectively). The higher stage indicates the better neurological recovery.

The five Times Sit to Stand Test (5STS) evaluates functional lower extremity strength. Participants will be asked to sit to stand for 5 times as quickly as possible. The time to complete the task will be recorded. The shorter duration (s) represents the better muscle strength in lower limbs.

The Berg balance scale (BBS) is used to objectively determine a participant's ability to safely balance during a series of predetermined tasks. It is a 14 item list with each item consisting of a five-point ordinal scale ranging from 0 to 4, with 0 indicating the lowest level of function and 4 the highest level of function. The total score is 56.

The Timed Up and Go test (TUG) is a simple test used to assess a person's mobility and requires both static and dynamic balance. It uses the time that a person takes to rise from a chair, walk 3 meters, turn around, walk back to the chair, and sit down. The longer duration (s) to complete the task represents the poorer balance.

Modified Clinical Test of Sensory Integration and Balance (mCTSIB) is designed to assess how well an older adult is using sensory inputs when one or more sensory systems are compromised. Postural sway will be measured using an accelerometer attached on the lower back in 4 sensory conditions with visual and proprioceptive manipulation.

Falls Efficacy Scale- International (FES-I) assesses subjects' concerns about falling. It consists of 16 questions related to everyday activities and subjects are asked to rate whether they were "not at all" (a score of 1), "somewhat" (2), "fairly" (3) or "very" (4) concerned about falling when doing that particular activity. The sum scores ranged 16 - 64 with higher scores indicating a greater fear of falling.

The Situational Vertigo Questionnaire (SVQ) is a 19-item questionnaire specifically aimed at identifying the presence of visual vertigo, a condition attributable to a defective vestibular compensation strategy, which is too dependent on the available visual information. Higher score represents more severe vertigo symptoms.

Gait pattern will be evaluated using a Opal wireless system. Participants will be asked to walk in a 14-meter walkway. The first and final 2 meters are designed for acceleration and deceleration. The middle 10-meter will be analyzed only.

The Barthel Index (BI) is an ordinal scale used to measure performance in activities of daily living (ADL). Ten variables describing ADL and mobility are scored. The total score is 100 and higher score represents more independent in ADL.