Final answer:
Changes in self-control during hypnosis stem from the heightened suggestibility under the power of suggestion, and the performance of the hypnotized social role expected by the individual, both influenced by changes in brain function and consciousness states.
Step-by-step explanation:
People in a hypnotic state may experience changes in self-control for a couple of key reasons. Firstly, due to the power of suggestion, where a clinician may use relaxation and suggestion techniques to influence thoughts and perceptions, individuals become highly suggestible and may act in ways they would not typically act while in full conscious control. Another reason relates to the concept of social-cognitive theory, where individuals behave according to social roles, meaning that in a hypnotic state, the individual is performing the role they believe is expected of them as a hypnotized person, which may differ from their normative behaviors. These altered states are generally associated with changes in brain functioning and a dissociation of consciousness, which can result in a divergence from typical self-control mechanisms.