Exposure exercises in imagination and in vivo are carried out in a gradual and prolonged manner. They are therefore included in trauma-oriented CBT under the term “prolonged exposure”. This strategy is, according to studies, the main component of traumatic recovery, as it affects the conditioning of fear (Bryant, 2016; Taylor, 2017). The purpose of exposure is to progressively reduce anxiety by gradually and persistently exposing the patient to troubling images or situations in such a way that he or she gets used to them, that they no longer produce painful emotional reactions and consequently the desire to avoid them. Specifically, the patient will initially be led to voluntarily face the memory of the traumatic event in session, in order to reduce cognitive intrusions and their impact on daily life. Afterwards, the patient will be encouraged to gradually expose himself to trauma-related situations, which he fears and avoids, in order to promote habituation. Repeated exposure, in a safe place such as the therapist’s office, also promotes awareness that trauma is a specific event that has occurred in another context. Several factors should be considered before undertaking exposure:

• Assess the individual’s safety, suicidal and homicidal risk, if he or she has a history of substance abuse, his or her coping skills and environmental support.
• Make sure that the rationale for this procedure is well understood.
• Make sure that the individual is stable and willing to collaborate. Otherwise, undertaking such an approach may decrease the person’s sense of control, exacerbate PTSD symptoms or comorbid disorders such as depression or substance abuse, lead to treatment dropout, or increase avoidance behaviours from all forms of treatment.
• If the individual is not ready to initiate exposure due to one or more of these reasons, the therapist should use other therapeutic strategies (e. g. stressor management, anxiety management) until the individual is ready.

Prolonged exposure in imagination

The underlying objective of imaginal exposure to the memories of the traumatic event is to allow habituation to the anxiogenic elements associated with the event. Prolonged imaginal exposure consists of thirteen steps. These must follow a specific order:

1. Explain the rationale for exposure to the individual. Explain that exposure exercises will be recorded using a tape recorder, which will be used for homework to be done between sessions with the therapist;
2. Determine, in collaboration with the individual, the scenario to which they will be exposed;
3. Test the individual’s anxiety level (using a scale from 0 to 10, with “0” meaning no anxiety and “10” meaning extreme anxiety);
4. Ask if they feel able to close their eyes;
5. Ask them to describe the event in detail using the present tense and the first person;
6. In the first few sessions, allow the individual to describe the event freely and at their own pace;
7. In the following sessions, ask direct questions;
8. Ask questions regularly about the individual’s anxiety level (using the same scale);
9. Identify avoidance behaviours;
10. Exposure should be carried out for 30 to 60 minutes;
11. Wait for the distress level to drop before ending the exercise;
12. Allow time before the end of the session for the distress level to drop (level < 5);
13. Explain the homework to be done for the next session (i.e. daily listening to the scenario at home).

At all times during exposure, the therapist must be sensitive to the individual’s dissociative reactions. If these occur, the therapist must use the anchoring techniques that they have previously taught the patient. They should also remind the individual to use anxiety management or anchoring techniques if the homework causes too much distress. The homework should be presented as follows:

1. Explain the rationale: to generalize the rehabilitation process to the patient’s home environment and possibly accelerate it;
2. Record or have the scenario of the event written once it is complete (usually after a few exposure sessions);
3. Ask them to listen to it or read it once or twice a day, noting their anxiety level before and after exposure (using the 0 to 10 scale);
4. Rediscuss self-observations during the next meeting.

Prolonged in vivo exposure

In vivo exposure is necessary when the victim feels a great deal of distress in the face of certain elements related to the strength of the aversive conditioning that occurred during the traumatic event. It is also necessary when avoidance symptoms (often resulting in behaviours that make the individual feel safe) interfere with the client’s daily functioning (e. g., not going out at night) or when cognitive restructuring is not possible or insufficient. In vivo exposure must be done gradually in order to allow the victim to undo the conditioned associations. Prolonged in vivo exposure consists of ten steps that follow a specific order:

1. Explain the rationale for the treatment to the individual;
2. Determine, in collaboration with the individual, the situations to which he or she will be exposed and establish a hierarchy from the least anxiogenic to the most anxiogenic situation.
3. Determine the situation to which the individual will be exposed before the next session (depending on the hierarchy);
4. Ask them to rate their level of anxiety before exposure (using a scale from 0 to 10);
5. Identify possible avoidance behaviours that can prevent exposure and find a way to work around it;
6. Ask the individual to expose themselves to the chosen situation at least 30 to 60 minutes before the next session;
7. If possible, ask them to wait until the distress level decreases before completing the exposure (level < 5);
8. Ask them to rate their level of anxiety after exposure (using a scale from 0 to 10);
9. Review of the exposure exercise at the next session;
10. Repeat steps 3 to 10 until all identified situations cause little anxiety (level < 3).

Each strategy targets specific and pre-defined therapeutic objectives, which the therapist can adjust according to the client’s needs and abilities. The strength of imaginary exposure is to reduce invasive symptoms (e.g., memories, flashbacks, dreams), reduce distress associated with internal event reminders, and more generally promote emotional integration of the trauma. In vivo exposure reduces invasive, avoidance and reactivity symptoms, promotes the return of previously avoided activities and improves the client’s autonomy. This approach also includes relapse prevention and preparation for retention as part of its strategies. The therapist and the client review all the symptoms presented at the beginning of the therapy and identify the progress made. The therapist works with the client to determine the potential causes of relapse and how he or she could prepare for such eventualities. This strategy helps to promote the client’s return to control (Brillon, 2013).