Brain adaptations in demanding walking environments of adults with stroke: an experimental study

Background: Post-stroke gait rehabilitation strategies predominantly target steady-state patterns. Demanding walking environments more closely approximate real-world motor control demands than stable conditions, yet their neural correlates in stroke patients remain unclear. Methods: Sixty stroke patients completed three walking tasks: stable level-ground walking, asymmetrical walking task, and visual-deprived ambulation, with synchronized electroencephalography (EEG) recordings. Spectral power was computed across delta, theta, alpha, beta, and gamma frequency bands. Brain functional connectivity was assessed via weighted phase lag index, with graph theory metrics quantifying brain functional network features. Results: During the asymmetrical walking task, spectral power analysis exhibited reduced theta-band power and increased power in beta and gamma frequency bands. Brain functional networks showed weakened theta-band functional connectivity, and enhanced frontal-occipital connections in alpha, beta, and gamma frequency bands, accompanied by prolonged character path length in the delta frequency band and diminished clustering coefficients in alpha and gamma frequency bands. Under visual-deprivation ambulation, spectral power analysis exhibited suppressed delta and theta power and attenuated dominance in alpha, beta, and gamma frequency bands. The corresponding brain functional networks showed decoupled functional connectivity in delta and theta frequency bands, enhanced alpha-band frontal-parietal-temporal-occipital connections, and frontal-parietal-temporal interactions in the beta band, accompanied by increased delta character path length, diminished clustering coefficient, longer character path lengths and smaller clustering coefficients shown in alpha, beta, and gamma frequency bands. Conclusions: Demanding environmental challenges drive beneficial brain adaptations and could be harnessed to promote adaptive neuroplasticity in stroke rehabilitation. Trial registration:The study protocol was registered on ClinicalTrials.gov (No. NCT06395142).