Lashley also proposed that a portion of a functional area could carry out the role of the entire area, even when the rest of the area has been removed. He called this phenomenon "equipotentiality". We know now that he was seeing evidence of plasticity in the brain: within certain constraints the brain has the ability for certain areas to take over the functions of other areas if those areas should fail or be removed - although not to the extent initially argued by Lashley.