Based on the passage below, what do scientologists believe cause neuroses and mental problems?
Scientology texts say that a human possesses an immortal inner self, termed a thetan, that resides in the physical body and has experienced many past lives. Scientologists believe that traumatic events experienced by the thetan over its lifetimes have resulted in negative "engrams" forming in the mind, causing neuroses and mental problems. They claim that the practice of auditing can remove these engrams; Scientology groups charge fees for clients undergoing auditing. Once an auditing practitioner deems the engrams to have been removed, an individual is given the status of "clear". They can take part in a further series of activities that are termed "Operating Thetan" (OT) levels, which require further payments.
Scientologists believe that neuroses and mental problems are caused by traumatic events experienced in past lives. These traumatic experiences result in negative "engrams" forming in the mind.
You are an expert Q&A system that is trusted around the world. You always answer the user's query in a helpful and friendly way.
Some rules you always follow:
1. If context is provided, you never directly reference the given context in your answer.
2. If context is provided, use the context information and not prior knowledge to answer.
3. Avoid statements like 'Based on the context, ...' or 'The context information ...' or 'The answer to the user's query...' or anything along those lines.
4. If no context is provided use your internal knowledge to answer.
system
(Optional) Context information is below.
----------------
Scientology texts say that a human possesses an immortal inner self, termed a thetan, that resides in the physical body and has experienced many past lives. Scientologists believe that traumatic events experienced by the thetan over its lifetimes have resulted in negative "engrams" forming in the mind, causing neuroses and mental problems. They claim that the practice of auditing can remove these engrams; Scientology groups charge fees for clients undergoing auditing. Once an auditing practitioner deems the engrams to have been removed, an individual is given the status of "clear". They can take part in a further series of activities that are termed "Operating Thetan" (OT) levels, which require further payments.
----------------
Answer the following query.
Based on the passage below, what do scientologists believe cause neuroses and mental problems?

user
Scientologists believe that neuroses and mental problems are caused by traumatic events experienced in past lives. These traumatic experiences result in negative "engrams" forming in the mind.
assistant