Dr Marlene Bönstrup | Low-frequency brain oscillations as a target for an on-demand brain stimulation in human motor rehabilitation

Advancement of neurostimulation-aided interventions for upper limb motor rehabilitation to clinical practice has so far been unsuccessful. An emerging new avenue of brain stimulation strongly relies on a close link between the stimulation effect and pathophysiology. It follows the rationale of an on-demand, closed-loop electric stimulation which is dynamically triggered by ongoing biological signals. Recently, an on-demand neurostimulation was shown to improve skillful reaching and grasping in an animal model of stroke. The neurostimulation reinstalled low-frequency brain oscillations (LFOs), a signal that was pathologically absent post stroke. Those are short bouts of oscillatory activity in the upper delta and lower theta range that appear in the local field potential of the contralateral motor cortex around reaching onset. Longitudinal recordings in stroke patients show that a lack of LFO generation also marked human motor cortex pathophysiology in the acute phase post stroke. Movement-preparatory LFOs progressively increased at 1 and 3 months. This re-emergence closely tracked the recovery of motor function across several movement qualities.

Thus, a targeted LFOs-restorative brain stimulation therapy may be a promising avenue for the development of an on-demand brain stimulation in human stroke patients to recover lost motor function.