Can psychological diseases such as fearful and depressive fears, which are temporarily sinking the spiritual efficiency strongly?
Yes, that can happen before, but that is not a permanent state. Stress is, if possible, to limit. Also some medications can cause concentration defects. That has nothing to do with stupidity! Ther best with your doctor about it.
Yes, mental illnesses change the metabolism in the brain, so you are unconquered and less powerful.
Yes, you may not have to
YES may be
Yes, because the brain is constantly under stress