The brain can change through conditioning, as demonstrated by Pavlov's experiments where a bell paired with food leads to salivation.

“So, these classic experiments by Ivan Pavlov simply show that the brain can change. Why does the salivation change because of a ringing bell? Because that's the thing that leads to this event being useful. It's useful to the dog to prepare for this activity, and so you condition this particular synapse to be strengthened, where normally bells just ring.”