This three-year study is proposed to document the effect and further implementation of error-augmented walking on gait performance and brain activities in individuals with stroke. Note that brain activations of post-stroke individuals during locomotion is a relatively unexplored realm. In the first year, study aims to observe the gait performance and brain activity of post-stroke and healthy participants when they walk on the split-belt treadmill, which inputs errors and causing adaptation during locomotion. Second year, study focuses on the long-term effect in aspect of brain activation and gait performance after training the post-stroke individuals with error-augmented treadmill walking. Lastly, study aim to investigate the long-term effect of practically applying the concept of error-augmented training strategy into clinical physical therapy.

The first-year study is a cross-sectional study to recruit post-stroke and healthy participants. Gait performance will be measured by GaitUp system and brain activity during each walking trails will be measured concurrently by functional near infrared spectroscopy (fNIRS). Cadence, stride time, stride length and swing cycle are the gait parameters that will be recorded. Also, symmetry ratio and variability of temporal and spatial parameters will also be calculated. Brain area of interest in this study will be bilateral premotor cortex (PMC), supplementary motor area (SMA) and medial part of primary motor cortex (M1). Study will run one-way analysis of variance (ANOVA) with repeated measures and, if needed, Tukey post hoc test will be used to document the within group and between group differences with p<.05.

The second year and third year study are single-blinded (assessor), randomized controlled trials. In the second year, study will recruit and randomize post-stroke participants into one of the two training groups, error-augmented treadmill training group (ETT group) and active control group (AC group). In ETT group, participants will practice split-belt treadmill walking. And participants in AC group will received traditional treadmill walking. The training duration will be 40 minutes per session, 3 sessions per week for a total of 4 weeks for every group. There will be three evaluations, chronologically, on one day before intervention, one day after completion of intervention and one month after completion of intervention. Gait performance, brain activity, dynamic gait index and sensorimotor ability of lower extremity will be documented. Two-way ANOVA and Tukey post-hoc test will be used to determine the training and follow-up effects with p< .05. During the third year, individuals with stroke will be recruited and randomized to one of the two group, error-augmented concept combined physical therapy group (EAPT group) and conventional physical therapy group (CPT group). Participants in the CPT group will receive thirty-minute conventional physical therapy each session. Instead of training on a split-belt treadmill, participants in EAPT group will receive fifteen-minute walking trainings that implement the error-augmented concept and another fifteen-minute conventional physical therapy each session. The training duration will be 40 minutes per session, 3 sessions per week for a total of 4 weeks for every group. The outcome measurements, and statistical analysis are the same as those described in the second year.

The inclusion criteria of stroke participants are

1. first unilateral stroke
2. older than 20 years old
3. medically stable
4. lesion site limited in subcortical area
5. having step length asymmetry (asymmetry ratio ≥ 1.08)
6. ability to walk 10 meters independently without an assistive device.

The inclusion criteria of healthy participants are

1. ability to walk 10 meters independently without an assistive device
2. no any other neurological, psychological, or orthopedic disorders known to interfere the walking performance
3. mini-mental status examination scores > 24 points

The exclusion criteria are

1. Participants who are medical unstable
2. cognitive impaired (mini-mental status examination scores < 24 points)
3. diagnosed with other neurological, psychological, or orthopedic disorders known to interfere the participation to the study
4. with the diagnosis which the contraindication includes exercise