Can the motor cortex learn any mapping a brain-computer interface gives it? · Grey Matter

Not within an afternoon.

Can the motor cortex learn any mapping a brain-computer interface gives it?

Not within an afternoon. In 2014 monkeys controlling a cursor from motor cortex were given new mappings of two kinds: ones that could be driven by combinations of activity the recorded population already produced, and ones that required patterns it never showed. They learned the first kind readily within a session and largely failed at the second. The circuit's existing structure limits which new patterns are easy to make, which may be why new skills come faster when they resemble ones already learned.