Benjamin Libet performed a series of experiments on the brain basis of voluntary action which have remained controversial ever since. Libet took advantage of a well-known phenomenon called the ‘readiness potential’ – a small slope-like EEG signal, originating from somewhere over the motor cortex, that reliably precedes voluntary actions. Libet wanted to know whether this brain signal could be identified not only prior to a voluntary action, but before the person was even aware of the intention to make the action.
