Rhythmic Haptic Cueing for Gait Rehabilitation of Hemiparetic Stroke and Brain Injury Survivors

This thesis explores the gait rehabilitation of hemiparetic stroke and brain injury survivors by a process of haptic entrainment to rhythmic cues. Entrainment to auditory metronomes is known to improve gait; this thesis presents the first systematic study of entrainment for gait rehabilitation via the haptic modality. To investigate this approach, a multi-limb metronome capable of delivering a steady, isochronous haptic rhythm to alternating legs was developed, purpose-built for gait rehabilitation, together with appropriate software for monitoring and assessing gait. A formative observational study, carried out at a specialised neurological centre, supplemented by discussions with physiotherapists and neuropsychologists, was used to focus the scope on hemiparetic stroke and brain injury. A second formative study used a technology probe approach to explore the behaviour of hemiparetic participants under haptic cueing using a pre-existing prototype. Qualitative data was collected by observation of, and discussion with, participants and health professionals. In preparation for a quantitative gait study, a formal experiment was carried out to identify a workable range for haptic entrainment. This led to the creation of a procedure to screen out those with cognitive difficulties entraining to a rhythm, regardless of their walking ability. The final study was a quantitative gait study combining temporal and spatial data on haptically cued participants with hemiparetic stroke and brain injury. Gait characteristics were measured before, during and after cueing. All successfully screened participants were able to synchronise their steps to a haptically presented rhythm. For a substantial proportion of participants, an immediate (though not necessarily lasting) improvement of temporal gait characteristics was found during cueing. Some improvements over baseline occurred immediately afterwards, rather than during, haptic cueing. Design issues and trade-offs are identified, and interactions between perception, sensory deficit, attention, memory, cognitive load and haptic entrainment are noted.