AUTHOR=Mokienko Olesya , Chervyakov Alexander , Kulikova Sofia , Bobrov Pavel , Chernikova Liudmila , Frolov Alexander , Piradov Mikhail
TITLE=Increased motor cortex excitability during motor imagery in brain-computer interface trained subjects
JOURNAL=Frontiers in Computational Neuroscience
VOLUME=7
YEAR=2013
URL=https://www.frontiersin.org/journals/computational-neuroscience/articles/10.3389/fncom.2013.00168
DOI=10.3389/fncom.2013.00168
ISSN=1662-5188
ABSTRACT=Background: Motor imagery (MI) is the mental performance of movement without muscle activity. It is generally accepted that MI and motor performance have similar physiological mechanisms.
Purpose: To investigate the activity and excitability of cortical motor areas during MI in subjects who were previously trained with an MI-based brain-computer interface (BCI).
Subjects and Methods: Eleven healthy volunteers without neurological impairments (mean age, 36 years; range: 24–68 years) were either trained with an MI-based BCI (BCI-trained, n = 5) or received no BCI training (n = 6, controls). Subjects imagined grasping in a blocked paradigm task with alternating rest and task periods. For evaluating the activity and excitability of cortical motor areas we used functional MRI and navigated transcranial magnetic stimulation (nTMS).
Results: fMRI revealed activation in Brodmann areas 3 and 6, the cerebellum, and the thalamus during MI in all subjects. The primary motor cortex was activated only in BCI-trained subjects. The associative zones of activation were larger in non-trained subjects. During MI, motor evoked potentials recorded from two of the three targeted muscles were significantly higher only in BCI-trained subjects. The motor threshold decreased (median = 17%) during MI, which was also observed only in BCI-trained subjects.
Conclusion: Previous BCI training increased motor cortex excitability during MI. These data may help to improve BCI applications, including rehabilitation of patients with cerebral palsy.