Dynamics of the bioelectric activity of the cerebral cortex after a stroke with imagining the movement of the ipsilesional hand

Background. In patients with post-stroke spastic hemiparesis, daily activities and self-care are largely determined by the function of the non-paretic hand. Although it is known that there is a motor deficit in a “healthy" hand, rehabilitation programs, however, are mainly aimed at the paretic hand. Currently, there are practically no approaches to the rehabilitation of the motor functions of the ipsilesional hand, so this aspect needs to be carefully studied. Objective. Evaluation of the bioelectric activity in the cerebral cortex in patients with post-stroke paresis of the upper limb before and after a course of rehabilitation exercises with intact hand movement imagination (MI) and using the brain-computer interface+hand exoskeleton (BCIE) in comparison with healthy subjects. Methods. We examined 5 right-handed patients (age - 61.1±0.5 years) with post-stroke hemiparesis, the period from the onset of the disease - 0.4±0.3 years, with a decrease in muscle strength 2-3 points according to the 6-point scale. The control group consisted of 5 healthy individuals of a similar age. BCIE was used for rehabilitation, 10 daily sessions were carried out. The EEG study was carried out on day 0, before the start of rehabilitation procedures, and on the day 30, 2 weeks after the end of the rehabilitation course. The power of EEG rhythms in a ten-second series of consecutive one-second epochs was analyzed. Results. In patients with right-sided hemiparesis, during the MI in the intact “healthy" hand, changes in the power of the mu- and alpharhythm were revealed compared to the results of examination of healthy ones - there was a “delay" in its decrease before the course of rehabilitation, and after course of rehabilitation, there was variable power loss during 1st second in both central and, similarly, in the posterior frontal leads. Thus, after BCIE sessions with MI in an ipsilesional «healthy» hand, altered bioelectrical phenomena, but similar to those occurring in healthy individuals, were found. Conclusion. The data obtained demonstrate the need not only for paretic hand exercises and bimanual training, but also for “healthy" hand exercises in the process of rehabilitation of patients with pyramidal hemiparesis, and also confirm the effectiveness of rehabilitation using BCIE.

ischemic stroke, pyramidal paresis, electroencephalography, brain-computer interface, motion imagination, ipsilesional hand