When trying to train a dog, I believe many experts now advocate the use of a clicker device. This is basically a flexible square of metal which, when deflected and released, emits a loud and consistent click: much more consistent than a word of command from an owner.
The idea apparently is to make the noise when the animal is behaving as required.
Today’s invention combines this with another form of Pavlovian reinforcement, the use of ‘treats.’
A container, similar to a saccharin tablet dispenser, would be used to spit out one treat pellet at a time. This action would deflect a metal plate, causing the required click.
The noise and pellet would reinforce each other’s effects and become associated with behaviour that was desired by the owner.