Alvaro Pascual-Leone did a study validating the importance of visualization. A group of volunteers practiced a five-finger piano exercise while neurotransmitters monitored their brain activity. As expected, neuroimaging revealed that the motor cortex was active while practicing the exercise. Then researchers told the participants to mentally rehearse the piano exercise in their mind. The motor cortex was just as active while mentally rehearsing as it was during physical practice. Researchers came to this conclusion: imagined movements trigger synaptic changes at the cortical level.
