Repeated unwanted thoughts are an unpleasant reminder of trauma. These thoughts might be triggered by a sight, sound, smell, person, place, or thing. But they can also appear without any recognizable trigger at all. In addition to bringing back painful memories, it’s possible for this re-experiencing to also bring back emotions (fear, sadness, anger, or shame) and physiological responses (racing heart, nausea, excessive perspiration, or dizziness) that were experienced during or after the trauma.

You might be wondering why a person would continually replay their worst experience. Shouldn’t trauma survivors just let it go and move forward? It would certainly be a relief to leave traumatic experiences behind us, but our brains often remain fixated and stuck in a repeated cycle of distressing thoughts and efforts to forget. This is because the human brain is designed to process and make sense of the world around us.

Most of the time, we excel at processing and categorizing the things we encounter. Usually this happens so efficiently that we are unaware of the process. Think about your drive to work or a meal you ate last week or last year. Do you remember all of the details of your journey or what you ate?  Unless something unusual happened, like the road was closed and you were late to work or someone cooked you a very special meal, specific details of routine events don’t require us to think much about them after the fact. These types of events are common in our lives, so our brains quickly determine how to process and categorize them. In contrast, a traumatic event falls so far outside our previous experience and expectation for how the world works that it presents a challenge for our brains. Our basic assumptions about safety and trust are violated which overwhelms our cognitive processes and coping. As a result, this causes our brains to repeatedly process the material as it tries to make sense of what happened.

When we’re awake, this repetitive processing involves intrusive recollections like chronic upsetting thoughts. It can also mean sudden intense feelings and thoughts that, at the extreme, can be difficult to distinguish from reality. These flashbacks can be so vivid that the individual responds as if the traumatic event is happening in the present moment. Fortunately, flashbacks are rare, but when they do occur they can be terrifying for the individual and anyone else who is around.

Intrusions can also happen when we’re sleeping. Under normal circumstances, dreaming allows the brain to process the things we experienced and to consolidate our memories. But in the case of trauma memories, as the brain struggles to make sense of the experience, it frequently results in upsetting dreams or nightmares. We may wake and remember the specific details of the dream or we may wake in a state of fear, drenched in sweat, shaking, and with a pounding heart. Repeated nightmares make falling asleep, staying asleep, and returning to sleep extremely difficult. Some people avoid sleeping altogether because of frequent nightmares.

Many trauma survivors avoid talking or thinking about what happened and the people, places and things associated with the event. Other survivors may try to numb their memories with addictive behaviors. Unfortunately, these strategies only provide a temporary reprieve and can contribute to greater suffering over time.

The good news is that there are treatments out there that work. Cognitive approaches help survivors process changes in the way they think about themselves, others, and the world following a trauma. Behavioral approaches help survivors confront their feared memories and address the activities that they are avoiding. Both strategies have been proven to foster healing and help trauma survivors get their lives back on track.