The way the brain is seen now is amazing. What was once thought to be a blob of reactive fat with simple connections and “compartments” is now clearly demonstrated as nothing less than one of the most vast universes mankind has ever explored. It is the mind in an organ and scientists look ceaselessly for a beginning only to find more unto no real end.
As much as certain mental health problems seem like they should be distilled down to single causes, this is an obtuse point of view. There are many factors which collide together to cause aberrant behavior and that is just the start of it. To a large extent, it is neurological conditioning. All people learn and sometimes there is exposure to negative experiences.
These experiences are repeated over and over and then the brain becomes habituated to this pattern based on certain stimuli. You come to understand this with study. Look into neuroscience training info to learn a bit more about how you can understand new theories of the brain and mind.
The good news is that the same neurological plasticity that created the negative conditioning can also recreate positive conditioning over the same imprint. In this way, one does not have to continually live out the neurosis again and again. It is like clearing mental karma in a way.
Using special techniques, patients can be taught how to think with better habituated patterns of positive thought and feeling of open possibilities rather than limitations. This boosts confidence and intelligence simultaneously. It is now understood that, when the brain is functioning in an optimistic state, new positive connections are formed at all times.
No matter what your level of interest is in this subject, you can always learn. There are online resources and courses you can take to better understand neuroscience and behavior.