focus of attention effect on sit to stand symmetry in individuals post stroke

Conditions: Stroke

Summary: the purpose of this study is to explore whether an external focus or internal focus of attention leads to improved motor performance and learning with increased use of the affected side during sit to stand in individuals post stroke. focus of attention refers to what a person is thinking about during a task, with an internal focus being thinking about what one's body is doing and an external focus being thinking about a target or outcome in the environment. a second purpose is to determine whether improved symmetry in sit to stand carries over to gait symmetry in individuals post stroke.

participant demographics including age, gender, weight, and height will be collected. self-selected gait speed, temporospatial gait parameters, and 5 times sit to stand, will be collected at baseline, immediately after, during short term retention (20 minutes after training), and long term retention (one hour after training is completed). gait speed and temporospatial parameters will be averaged across four passes over the gaitrite mat with participants being instructed to 'walk past the end of the mat at a normal comfortable pace'. the 5 times sit to stand test will be completed from an 20" height and participants will be instructed, "stand up and sit down 5 times as quickly as possible without using arms". participants will then be seated on a pressure mat placed on hi-lo table at a height where the participant's thigh is parallel to the floor, with an imu marker on the manubrium. the participant's feet will be placed on an hr pressure mat at a comfortable width with toes being in line with one another. tape marks will be placed at initial foot and buttocks position to allow for a consistent positioning throughout all trials. for baseline measurement, participants will perform sit to stand three times. during baseline, participants will be instructed to "please stand up without arms if possible". immediately post training, during short term, and long term retention participants will be told, "using the strategy used during training, please stand up without using arms three times" and "please stand up normally". average force under the affected side/average overall force during the sit to stand transition will be captured on the hr pressure mat located beneath the participants feet. participants will be categorized into groups based on stroke chronicity with those who have had a stroke within 6 months being placed in the subacute group and those with a stroke greater than 6 months being categorized in the chronic group. within their stroke category they will be randomized into either the internal or external focus group using a random number generator. each participant will perform 3 trials of sit to stand at baseline, short term, and long-term retention. during training, participants will perform sets of sit to stands with the mat at progressively lower heights, with differing cues based on group allocation. one set of sit to stands to 10 or form fatigue or rpe rating \>16/20 will occur 30% above baseline, 20%, and 10% of the starting mat height. if participants are unable to complete 10 the number completed will be recorded for each trial. two minute rest breaks will occur between each set or until the paricipant reports a rate of perceived exertion (rpe) of \<11/20 on the borg rpe scale. prior to training the participants will be given a demonstration. the external focus group will be told, "stand up and sit down trying to keep the orange targets and the blue targets as close together as possible, like this." the internal focus group will be told, "stand up and sit down trying to keep the r/l shoulder and r/l hip as far to the r/l as possible, like this." participants will be asked to perform one repetition, "show me". corrections will be given based on participant performance and group allocation. during acquisition trials the external focus group will have foam circles taped to their lateral shoulder and lateral hip. matching circles will be placed half the body width plus 10cm to their side in line with the feet. see figure 2. this distance will be determined by taking the girth in sitting. participants will be instructed to 'bring the targets together as participants stand up. the internal focus group will be instructed to bring the left/right shoulder and hip as far to the left/right as possible. feedback will be provided according to group allocation. center of pressure beneath the feet at the maximum lateral excursion towards the affected side, as well as the average throughout sit to stand will be analyzed at baseline, during acquisition trials, immediately after training, 20 minutes later, and 1 hour after training. trunk alignment will also be captured at these same times with the imu. during the 20 minutes between the training and short term data collection participants will complete a post manipulation questionnaire regarding what participants were thinking about during sit to stand training. during the hour between short term and long-term retention participants will complete a general health questionnaire and the montreal cognitive assessment (moca) to explore cognitive status. one week later participants will return and complete the same protocol in the opposite group initially assigned. both sessions should last less than two hours.

Eligibility criteria:
inclusion criteria: * stroke \>1 month * must be able to perform sit to stand from a standard height 20" chair without physical assistance * must be able to walk 20 feet with or without an assistive device at a contact guard to independent level * follow 3 step motor commands. exclusion criteria: * contraversive pushing * neglect as evidenced by \<44/54 on the star cancellation test * any orthopedic conditions that impact their ability to transition from sit to stand will be excluded from the study. * any other neurologic conditions that impact their ability to transition from sit to stand will be excluded from the study.

Keywords: motor learning focus of attention sit to stand