Changes in the Cortical Silent Period in a Motor-Imaginary Type Brain Computer Interface

Brain-computer interface (BCI) is a technology that facilitates the exchange of information between the brain and external devices by processing electrical signals from the cerebral hemispheres. This technology can be applied in the development of neuro-training systems for individuals who have suffered a stroke. The rehabilitative capabilities of BCIs are based on the activation of brain areas responsible for specific functions, leading to their recovery due to brain plasticity. The physiological manifestation of increased activity is a change in cortical excitability, which can be measured using transcranial magnetic stimulation (TMS). In this study, we investigated the possibility of using a method for assessing cortical excitability based on motor evoked potentials (MEP) and the cortical silent period (cSP). The cortical silent period is a period of suppression of electrical, including background, muscle activity recorded using electromyography (EMG). This period occurs as a result of the motor evoked potential following transcranial magnetic stimulation of the primary motor cortex of the motor center of the target muscle. The cSP is a result of inhibitory mechanisms that arise after MEP. It provides a broad temporal assessment of spinal and cortical inhibition.