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Summary

Imaginal exposure is a specific exposure technique, used primary when exposure in-vivo is not feasible. The most common use of imaginal exposure is during a CBT for posttraumatic stress disorder (exposure for the traumatic memories). Imaginal exposure follows the same basic principles of exposure as when it is used in-vivo (see separate article), but instead of seeking out the phobic stimulus in the real world (as during in-vivo exposure), the focus of exposure is a phobic mental image or memory.

Principles and practice

As with all types of exposure, imaginal exposure is preceded by functional analysis (see separate article) of what mental images or memories the patient suffers from, what triggers the patient’s anxiety and what avoidance patterns maintains the fear.

In functional terms, it is important to stress that most anxiety problems are composed of both overt (external) and covert (internal) components, and that avoidance of one often entails avoidance of the other. This means that in-vivo and imaginal exposure, especially in therapy with certain patients, intertwines. An example of this is in exposure therapy for a patient with posttraumatic stress disorder (PTSD): During an in-vivo exposure for the specific place where the patient suffered an assault, not only the place in itself (external stimulus) may evoke conditioned anxiety, but the fact of being there may also evoke specific memories or even flash-backs of the traumatic event (internal stimuli). This means that the exercise in a strict sense no longer constitutes just in-vivo exposure but also simultaneous imaginal exposure (to the memory).

The five principles of exposure

As with all exposure, imaginal exposure as a specific therapeutic intervention follows 5 principles.

For it to be effective, all exposure should be:

• planned and structured (by the therapist, in collaboration with the patient)

• gradual (by way of a exposure hierarchy, introduced by the therapist, in collaboration with the patient)

• prolonged (that is, be sufficiently long as to enable new non-fearful experiences)

• repeated (that is, be done a sufficient number of times, which also enables experiencing something new over time)

• without safety behaviours (that is, without the patient trying to distract him or herself or seeking other forms of temporary safety or temporary relief during exposure) (see separate article).

The principle of exposure being prolonged has been particularly stressed when it comes to treatment of PTSD: The primary, evidence-based CBT treatment protocol for PTSD, developed by Edna Foa, is called Prolonged exposure.

The specific principles of imaginal exposure

After having conceptualised the different kinds of distressing memories or mental images (during the case conceptualisation and functional analysis, see separate articles), the therapist wants to assess how relatively distressing they are, in order to engage with a gradual exposure (that means hierarchising the different mental images/memories from the least distressing to the most distressing).

After choosing specific memory or mental image or “scene”, the therapist starts the imaginal exposure: The patient is asked to close his or her eyes and describe the memory/scene in the first-person and in the present tense (“Describe it to me as it was a movie scene that you are seeing, as it was happening now”). Furthermore, the patient is asked to involve as many senses as possible: to describe not only what he or she sees, but also what she feels, smells and experiences inside, during the exposure.

The therapist identifies the most anxiety provoking part of the scene: its “hot-spot” (by regularly asking how much subjective fear it evokes, see separate article: “Subjective units of distress”)

As in in-vivo exposure, the therapist will, during imaginal exposure, ask the patient questions like “What goes through your mind right now” (to help identifying safety behaviours our subtle avoidance). The therapist will also guide the patient by asking him or her to focus on the anxiety provoking stimulus (“Try to go back and describe exactly what you see” “Try to stay with it”). The therapist also wants to continually assess the patient’s level of anxiety (“What is your level of anxiety at this moment?”) and provide support (“I can see how difficult this is for you, you are so brave!”).

The scenes is worked through and repeated as many times as needed, until the patients anxiety is lower or until he or she has experienced something new.

Evaluation after exposure: The therapist goes through with the patient how he or she experienced the exposure and they together decide upon homework for the next session, in connection to the exposure they just did during the session.