Characteristics of the specific brain functional network correlate with the latency of motor imagery

Motor imagery is a widely used technique in neurophysiological research and brain-computer interface applications for restoring lost motor functions. This study aimed to analyze the neural correlates of motor imagery at the level of brain functional networks using electroencephalography (EEG). Thirty subjects performed motor executions, quasi-movements, and imaginary movements while EEG data were recorded. We explored the correlation between the latency of motor imagery and the characteristics of brain functional networks in the alpha- and beta-frequency ranges. The analysis revealed a number of nodes within the network whose local cluster coefficients negatively correlated with the time of motor imagination onset. This indicates that a decrease in the corresponding networks metrics would lead to improved rate of motor imagination. These nodes were predominantly located in the frontal cortex, parietal, and temporal lobes. The identified nodes, particularly the Frontal Mid L zone, hold promise as potential targets for non-invasive brain stimulation techniques such as transcranial magnetic stimulation or transcranial direct current stimulation. Stimulating these areas may enhance motor imagination ability and facilitate the rehabilitation process, especially for stroke patients with severe motor impairment.