Extended enhancement of corticospinal connectivity with concurrent cortical and peripheral stimulation controlled by sensorimotor desynchronization

• Published in: Brain stimulation Vol. 11; no. 6; pp. 1331 - 1335
• Main Authors: Guggenberger, Robert, Kraus, Dominic, Naros, Georgios, Leão, Maria Teresa, Ziemann, Ulf, Gharabaghi, Alireza
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2018
• Subjects: Adult; Brain-computer interface; Brain-Computer Interfaces; Brain-robot interface; Closed-loop stimulation; Electroencephalography - methods; Evoked Potentials, Motor - physiology; Female; Humans; Imagination - physiology; Male; Motor Cortex - physiology; Motor map; Movement - physiology; Paired associative stimulation; Pyramidal Tracts - physiology; State-dependent stimulation; Transcranial Magnetic Stimulation - methods; Young Adult; Brain-computer interface; Motor map; Closed-loop stimulation; State-dependent stimulation; Brain-robot interface; Paired associative stimulation
• ISSN: 1935-861X; 1876-4754; 1876-4754
• DOI: 10.1016/j.brs.2018.08.012

Pairing cortical and peripheral input during motor imagery (MI)-related sensorimotor desynchronization (ERD) modulates corticospinal excitability at the cortical representation (hotspot) of the imagined movement. To determine the effects of this associative stimulation protocol on the cortical motor map beyond the hotspot. In healthy subjects, peripheral stimulation through passive hand opening by a robotic orthosis and single-pulse transcranial magnetic stimulation to the respective cortical motor representation were applied in a brain-machine interface environment. State-dependency was investigated by concurrent, delayed or non-specific stimulation with respect to ERD in the beta-band (16–22 Hz) during MI of finger extension. Concurrent stimulation led to increased excitability of an extended motor map. Delayed and non-specific stimulation led to heterogeneous changes, i.e., opposite patterns of increased excitability in either the center or the periphery of the motor map. These results could be instrumental in closed-loop, state-dependent stimulation in the context of neurorehabilitation. •Motor imagery, cortical & peripheral stimulation increase corticospinal excitability.•Pairing all three modalities increases excitability of an extended motor map.•The center and periphery of the motor map respond differently to paired stimulation.•This may be important for motor restoration following corticospinal tract lesions.