Different forms of neurostimulation in humans have now been shown to boost our ability to learn and perform motor actions, to pay attention to events in the environment, to recall information in memory, and to exercise self-control. At the same time, evidence is mounting for more complex effects on cognition. For instance, stimulation of the human prefrontal cortex can enhance or inhibit our tendency to lie, improve ourability to lie successfully, and can encourage us to comply with social norms that carry a punishment for disobedience.