Premotor cortex is involved in restoration of gait in stroke

Abstract

Cortical activation during hemiplegic gait was assessed in six nonambulatory patients with severe stroke (four men, two women; four with right and two with left hemiplegia; 57 years old and 3 months after stroke on average), using a near-infrared spectroscopic imaging system. Each patient performed tasks of treadmill walking (0.2km/hr), alternated with rest every 30 seconds for four repetitions, under partial body weight support, either with mechanical assistance in swinging the paretic leg control (CON) or with a facilitation technique that enhanced swinging of the paretic leg (FT), provided by physical therapists. Gait performance was associated with increased oxygenated hemoglobin levels in the medial primary sensorimotor cortex in the unaffected hemisphere greater than in the affected hemisphere. Both cortical mappings and quantitative data showed that the premotor activation in the affected hemisphere was enhanced during hemiplegic gait. There was also a prominent activation in the presupplementary motor area. Overall cortical activations and gait performance were greater in walking with FT than with CON. These indicate that multiple motor areas including the premotor cortex and presupplementary motor area might play important roles in restoration of gait in patients with severe stroke.

Adaptive locomotor network activation during randomized walking speeds using functional near-infrared spectroscopy

“…In tandem with the PFC, the SMA is an important region in human locomotion and finetuning balance with increased walking speed. In previous literature, spinal locomotor pattern generators have been primarily thought to mediate rhythmic locomotor movement [17][18][19]. However, based on this assumption, we should have observed a decrease in cortical activation associated with increased walking speeds.…”

Ankle dorsiflexion as an fMRI paradigm to assay motor control for walking during rehabilitation

“…Can functional neuroimaging reflect training-related reorganization and provide a physiological insight into the optimal dose of additional gait training? Walking is not feasible during fMRI but has been performed during near-infrared spectroscopy (NIRS) (Miyai et al, 2001(Miyai et al, , 2002, 18 fluorodeoxyglucose PET (Dobkin, 1996), and single photon emission computerized tomography (Fukuyama et al, 1997). Bilateral cortical activity was found in primary and secondary motor cortices and the cerebellum.…”

Applications of Near Infrared Spectroscopy in Neurorehabilitation

“…In hemispheric stroke patients with supratentorial lesions, activation in the motor-related cortex in the affected hemisphere increases with functional recovery. Particularly, the premotor cortex in the affected hemisphere appears to be essential (Miyai et al, 2002(Miyai et al, , 2003, as a previous observational study had suggested (Miyai et al, 1999). On the other hand, ataxic stroke patients with infratentorial lesions display a different activation pattern during gait.…”