Changes in cerebello-motor connectivity during procedural learning by actual execution and observation.
The cerebellum is involved in motor learning of new procedures both during actual execution of a motor task and during observational training. These processes are thought to depend on the activity of a neural network that involves the lateral cerebellum and primary motor cortex (M1). In this study, we used a twin-coil TMS technique to investigate whether execution and observation of a visuomotor procedural learning task is related to modulation of cerebello-motor connectivity. We observed that, at rest, a magnetic conditioning pulse applied over the lateral cerebellum reduced the motor-evoked potentials obtained by stimulating the contralateral M1, indicating activation of a cerebello-motor connection. Furthermore, during procedural learning, cerebellar stimulation resulted in selective facilitation, not inhibition, of contralateral M1 excitability. The effects were evident when motor learning was obtained by actual execution of the task or by observation, but they disappeared if procedural learning had already been acquired by previous observational training. These results indicate that changes in cerebello-motor connectivity occur in relation to specific phases of procedural learning, demonstrating a complex pattern of excitatory and inhibitory drives modulated across time.
Torriero
Sara
S
IRCCS Fondazione Santa Lucia, Rome, Italy. s.torriero@libero.it
Oliveri
Massimiliano
M
Koch
Giacomo
G
Lo Gerfo
Emanuele
E
Salerno
Silvia
S
Ferlazzo
Fabio
F
Caltagirone
Carlo
C
Petrosini
Laura
L
D000328:Adult; D000704:Analysis of Variance; D001931:Brain Mapping; D002531:Cerebellum / Q000502:physiology*; D004576:Electromyography / Q000379:methods; D019054:Evoked Potentials, Motor / Q000502:physiology; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology*; D019370:Observation; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation / Q000379:methods; D055815:Young Adult