This sounds right for me. When my thinking is negative and my mind cycles around and around, these negative thoughts can create sad feelings which are negative. If I feel sad enough and for prolonged periods of time my sad feelings will create moods which can last for a short time or deepen into moods which gradually darken our thinking to the extent that hopelessness begins to rule our emotions-our lives. Once our moods deepen, we begin to find ourselves prisoners, not of any iron bars and locked cells, but the change in our thinking, now negative and hopeless , not only will change our behaviors so that any physical, mental or spiritual activities will come to a halt All those activities that were once such a large part of our lives, providing pleasure for us, gradually have all disappeared. From this time on, our thinking, our feelings, frozen with fear and anxiety are stuck in a place which is unable to provide any possible solutions providing a predictable escape.