Everything we have ever done has left a mark on our subconscious mind. Our subconscious mind is like a computer. It records everything we have ever experienced through our senses. In other words it records everything we see, hear, touch, taste, smell and even everything we think.
The technique we use in hypnosis to assist a person to remember past events is called regression.
Some people get regressed because they need more details about a specific event, for example someone who witnessed a crime. Usually when you are in a traumatic situation like witnessing a crime, your stress level becomes very high. Because you usually feel overwhelmed at that point in time, it stands to reason that that you think you can’t remember the details.
Through regression you can go back to that event and recall all the details that your subconscious mind has stored.
Another reason people use regression, is when they are having a specific problem or behavior that they cannot seem to stop. Sometimes things happen in our past that affects our behavior. When we go back to the time the problem started, we become more aware of what happened and it helps us to understand the problem.
It also helps us to see how it relates to the present and usually understanding a problem helps relieve a problem.