Final answer:
In Freudian psychology, a defense mechanism protects a person's consciousness from anxiety-provoking material by employing unconscious behaviors to mitigate felt anxiety and internal conflict.
Step-by-step explanation:
In Freud's usage, a defense mechanism has the effect of protecting the person's consciousness from threatening material. Defense mechanisms are unconscious protective behaviors that work to reduce anxiety. They are employed by the ego to protect the individual from being overwhelmed by anxiety. These mechanisms operate in various ways that can distort reality.
One example is repression, where anxiety-causing memories are blocked from consciousness. In reaction formation, a person expresses feelings or behaviors opposite to their actual desires. Regression involves reverting to a more immature behavioral stage when confronted with stress. Other mechanisms include projection, rationalization, displacement, and sublimation.
Freud's theories emphasize that the ego, conscious of reality, resorts to these unconscious strivings in order to manage internal conflicts and social pressures, often stemming from the desires of the id and the moral constraints of the superego.