Chapter 18

Exposure Strategies

Carolyn D. Davies, MAMichelle G. Craske, PhD

Department of Psychology, University of California, Los Angeles

Definitions and Background

Exposure refers to the process of helping a client repeatedly face a feared stimulus in order to learn new, more adaptive ways of responding and to reduce the anxiety and fear associated with the stimulus. A stimulus targeted by exposure can include animate or inanimate objects (e.g., spiders, elevators), situations or activities (e.g., public speaking), cognitions (e.g., intrusive thoughts about contamination), physical sensations (e.g., heart racing), or memories (e.g., distressing memories of an assault).

Exposure is recognized as a highly effective behavioral strategy for treating a range of anxiety and fear-related problems, including panic disorder, agoraphobia, social anxiety disorder, post-traumatic stress disorder (PTSD), and obsessive-compulsive disorder (OCD; Stewart & Chambless, 2009). From its earliest days, exposure has been central to the behavioral and cognitive therapies through the use of systematic desensitization to treat phobias and anxiety disorders (Wolpe, 1958).

Theoretical Basis

Fear (an emotional response to imminent threat) and anxiety (an emotional response to anticipated or potential threat) can develop after a person has a direct, negative experience with an object or situation (through a process called classical conditioning), observes the aversive experiences or fearful behavior of others (called vicarious conditioning), or receives threat-laden information from others. Following these experiences, a previously neutral object or situation can become associated with danger, leading to fear responses and anxiety, negative expectations about the feared stimulus, and associated behaviors (e.g., avoidance) upon subsequent encounters with the stimulus. Furthermore, the fear can generalize to include other associated objects or situations. For example, a woman who got stuck in an elevator for several hours as a child became extremely fearful of enclosed places, to the point that she would have a panic attack in an array of situations if she felt trapped. She avoided taking elevators at all costs, and her fear and avoidance of elevators generalized to other similar situations, such as being in a small room, sitting in the middle of the row in an auditorium, and even being stuck in traffic.

Avoidance behaviors are central to the maintenance of fear and anxiety. While avoidance or escape behaviors can temporarily reduce distress, they maintain anxiety and fear in the long run by preventing new learning from occurring. In effect, exposure is designed to remove avoidance behaviors so that maladaptive beliefs are not reinforced and new learning can occur.

How Does Exposure Work?

Exposure relies on processes that facilitate new learning. One of these processes is called inhibitory learning, which has been extensively examined through studies using extinction. Akin to exposure, extinction involves presenting a feared stimulus repeatedly without its associated aversive outcome. Through extinction, an individual forms a new association with the stimulus so that two competing associations exist: one excitatory association that connotes danger and one inhibitory association that connotes safety. Thus, following an extinction procedure, an individual will have memories of the stimulus associated with both danger and safety (Bouton, 2004). Using the elevator example, after completing several exposures of riding an elevator without getting stuck, the client would now have two different associations tied to elevators: one that signals danger or getting trapped (excitatory association) and another that signals safety (inhibitory association). Much of the research on improving exposure focuses on examining ways to enhance inhibitory learning in order to strengthen and promote the retrieval of inhibitory associations (Craske, Treanor, Conway, Zbozinek, & Vervliet, 2014). A number of strategies for enhancing inhibitory learning have been tested and are described in the section “Enhancement Strategies.”

The reduction of fear responses during exposure sessions does not appear to be necessary for improvement (Craske et al., 2008), however, and thus may not be the primary driver of change. Psychological acceptance (see chapter 24) and cognitive defusion (see chapter 23) may facilitate exposure outcomes (Arch et al., 2012), particularly among people with multiple problems (Wolitzky-Taylor, Arch, Rosenfield, & Craske, 2012) or high levels of behavioral avoidance (Davies, Niles, Pittig, Arch, & Craske, 2015). Finally, increases in self-efficacy as a result of completing exposures may also play a role in facilitating an individual’s engagement in and improvement from exposure therapy (Jones & Menzies, 2000).

Types of Exposure

Exposure can be implemented as a component within a treatment plan or as a treatment by itself. A number of treatment protocols and manualized treatments include exposure, including prolonged exposure therapy for PTSD (Foa, Hembree, & Rothbaum, 2007) and exposure and response prevention for OCD (e.g., Foa, Yadin, & Lichner, 2012), but the basic principles of exposure are the same, regardless of diagnosis or treatment manual.

Exposures are highly individualized to the client’s own fears and avoidance behaviors and therefore must be collaboratively designed by the therapist and client. Typically, the therapist and client agree upon a hierarchy of feared situations and work through this list of exposures over the course of approximately twelve to fifteen sessions, with both in-session and between-session exposures assigned for homework. In-session exposures allow the therapist to help design and model exposures, guide and reinforce behaviors, and gauge progress. Between-session exposures are critical for increasing learning and improving clinical outcomes, as they allow for an increased frequency and a variety of exposures in settings without the therapist. There are three main types of exposure.

In vivo exposure involves direct exposure to live situations or objects. For example, a therapist with a client who fears public speaking might ask him to give a speech in front of an audience; for a client with a phobia of blood and/or injections, the therapist might ask her to look at pictures or videos of a blood draw and eventually have the client have her blood drawn at a clinic. Virtual reality exposure therapy can be used for situations that are difficult to access.

Interoceptive exposure refers to the deliberate induction of physical sensations, such as increased heart rate, light-headedness, or shortness of breath. Interoceptive exposure is relevant for clients who experience any type of panicky sensations or heightened concern with bodily sensations. Common interoceptive exposures include running in place, hyperventilation, staring in a mirror, breathing through a straw, and spinning in a circle.

Imaginal exposure is most helpful when it is not possible or feasible to access a feared situation in vivo or when an image itself is the feared stimulus (such as in OCD or PTSD). During imaginal exposure, clients vividly imagine and describe a feared scenario in detail, using first-person, present-tense language. Clients then record and repeatedly listen to the scenario. A variation on imaginal exposure is written exposure, which involves writing out, in detail, a feared scenario and repeatedly reading it. Examples of imaginal exposure include imagining getting fired from a job (for a client who worries excessively about making a mistake at work and getting fired) or imagining a traumatic event that occurred during combat (for a soldier with PTSD).

Implementation

Before beginning exposure therapy, the therapist must have a clear understanding of how exposure will be helpful for the client. Thoroughly assessing fear and anxiety, including the role that avoidance behaviors play in the client’s distress, will help the therapist and client develop and stick to an exposure treatment plan. Furthermore, because exposure is inherently anxiety provoking, providing a strong rationale and obtaining a client’s agreement to the treatment plan is a critical element of exposure.

When providing the rationale for exposure, the primary point to relay is that avoidance behaviors, though temporarily anxiety relieving, can increase distress and maintain fear and anxiety in the long run. In the example dialogue below, the therapist first assesses avoidance behaviors with a client who experiences panic attacks.

Therapist: When we feel anxious or afraid, our natural response is to try to avoid or get away from whatever is making us feel that way. What are some situations that you avoid?

Client: I think it’s mainly around driving for me. I used to be able to at least drive in the right lane on the highway, but now I can only drive on side streets. I also avoid driving over bridges.

Therapist: Okay, so driving on highways and bridges. What about other situations? Are there any activities or places you avoid?

Client: Well, I don’t like big crowds either. My son wanted me to take him to see a movie that just came out last week, but the thought of standing in line and then sitting in that crowded theater… I couldn’t bring myself to do it. My sister took him instead.

Therapist: These behaviors—avoiding crowds and driving only in certain areas—are very common responses to anxiety and panicky feelings. Avoidance is a natural response to situations that we think are threatening or scary. Unfortunately, too much avoidance can interfere with our lives and prevent us from doing things we want to do. In what ways do you think avoidance behaviors have impacted you?

Client: It’s impacted me a lot. The hardest part has been with my son. I feel terrible that I can’t take him places he wants to go or enjoy things with him. That’s definitely the worst part about all of this.

A few important points should be noted from this dialogue. First, the therapist provided some psychoeducation about avoidance behaviors. Second, the therapist began to identify avoidance behaviors as the problem (rather than anxiety or fear per se), as these behaviors will be the target of exposure. Third, the therapist elicited examples of how avoidance behaviors interfere in the client’s life. After responding with appropriate validation, the therapist can then provide an introduction to exposure.

Therapist In addition to interfering with our lives, avoidance also prevents us from learning that bad outcomes don’t always occur or aren’t as bad as we first thought. So even though avoidance can sometimes provide temporary relief from anxiety, in the long run it can actually make anxiety worse, which can then lead to even more avoidance. For this reason, the focus of this treatment is to decrease avoidance by approaching or confronting situations and sensations that you avoid. I know this can be difficult, so we are going to start gradually and work our way toward situations that are more difficult. How does this sound to you?

After checking with the client to make sure she understands the rationale for exposure, the therapist and client can begin to create a plan for exposures using the following steps.

1. Create a hierarchy. The first step to designing exposures is to create a list of feared situations (also called a fear hierarchy) and their associated fear ratings (on a scale of 0 to 10, with 10 being the most extreme). This list should include a variety of situations that elicit mild (3 to 4), moderate (5 to 7), and high (8 to 10) levels of fear or anxiety. Additionally, the hierarchy should include situations that can be targeted with in vivo, interoceptive, and imaginal exposure. The therapist and client work together to create this list and can continue adding to it as needed.

As part of the list-generation step, the therapist can complete an assessment of interoceptive exposures in order to identify the physical sensations that need to be targeted. The therapist models each interoceptive exercise (running in place, spinning in a circle, etc.), then the client completes the exercise, aiming to continue for approximately one minute. After each exercise, the therapist gathers two ratings from the client: level of fear or anxiety and level of similarity to sensations experienced when anxious. Interoceptive exposures that elicit high levels of similarity and moderate to high levels of fear or anxiety should be added to the exposure hierarchy.

2. Choose a first exposure. Strictly adhering to the order of the hierarchy is not necessary, but initial exposures should start at the lower end, at a fear level of approximately 3 or 4. This allows the client to understand the procedure of exposure and to build some self-efficacy, which may help the client engage in more difficult exposures later on.

3. Identify the anticipated negative outcomes. Before beginning an exposure, the therapist elicits the client’s expected or anticipated outcomes. This allows the therapist and client to “test out” a hypothesis about the outcome of an exposure and encourages the client to become a “scientist” who tests predictions and gathers evidence. Importantly, an expected outcome must be testable and observable. For example, for the client with the panic attacks described above, a hypothesis she might test out during interoceptive exposure is, “If I spin in a circle for more than half a minute, I will faint.” Once a testable outcome is obtained, the therapist can then ask, “On a scale of 0 to 100, how likely is this to occur?”

A second piece of information that is helpful to gather prior to an exposure is a rating of how bad it would be if the anticipated negative outcome did occur. For example, the therapist can ask, “On a scale of 0 to 100, how bad would it be if you did pass out as a result of the exposure?” This question can be especially helpful for situations in which the anticipated outcome may actually occur (e.g., rejection in the case of a social anxiety exposure), after which clients may learn that the outcome was not as bad as they had initially anticipated.

4. Test out the anticipated negative outcome. The therapist and client then decide on the best exposure to test out the client’s anticipated negative outcome. Importantly, the amount of time the client engages in the exposure is predetermined, based not on the level of fear reduction during the exposure but on what the client needs to learn. For example, for the client who experiences panic attacks, the exposure might consist of spinning in a circle for one minute (see table 1). This approach not only helps maximize expectancy violation (see the “Test it out” strategy for enhancing exposure in the following section), but it also encourages the client to focus on behavioral outcomes as the goal rather than fear reduction.

5. Ask follow-up questions following exposure. Following each exposure, the therapist asks the client targeted questions about what happened. For example, “Did what you were most worried about happening actually occur?” or “What did you expect to happen versus what actually happened?” or “Were you able to handle the distress or discomfort?” Throughout exposure work, the therapist identifies and reinforces approach behaviors (behaviors that move toward previously avoided situations) with the goal of helping the client engage in behaviors despite feelings of anxiety.

Table 1. First-exposure exercise for a client with panic disorder

An example of a first-exposure exercise for a client with panic disorder. Additional exposures are designed in this same way, usually increasing in difficulty as sessions proceed.

Before Exposure Goal: What are you most worried will happen? On a scale of 0 to 100, how likely is it that this will happen? On a scale of 0 to 100, how bad would it be if this did happen?	Spin in a circle for one minute. I will faint. 85 95
After Exposure Yes or no, did what you were most worried about occur? How do you know? What did you learn?	No. I remained conscious. Feeling dizzy doesn’t necessarily mean I am going to faint.

Enhancement Strategies

Research on inhibitory learning during exposure has led to the identification of strategies that therapists can use to refine and enhance exposure. These strategies, along with their theoretical bases, detailed in a previous paper from our lab (Craske et al., 2014), are summarized below.

Expectancy violation—“Test it out.” The basic idea of this strategy is to maximize the difference between the anticipated negative outcome and the actual outcome during an exposure; it’s based on the premise that the mismatch between expectancy and outcome is critical for new learning (Hofmann, 2008). The therapist should attempt to emphasize this mismatch as much as possible by (1) having the client identify specific expectations about an aversive outcome prior to an exposure; (2) designing the exposure to test out this expectancy; (3) determining the duration of the exposure based on what is needed to violate expectancies, not based on the reduction of fear levels; and (4) asking clients, after each exposure trial, to judge what they learned (for example, “What surprised you about doing the exposure? What did you learn from doing this exposure?”) Furthermore, therapists should refrain from using cognitive restructuring strategies prior to exposures, as these interventions are designed to reduce the expectancy of a negative outcome and may thereby reduce the mismatch between the client’s initial expectancy and the actual outcome.

Deepened extinction—“Combine it.” This strategy combines multiple feared stimuli, or cues, in one exposure. After conducting exposure to each cue individually, both cues can then be combined to deepen the learning process. For example, imaginal exposure to an obsession, such as the obsession to stab a loved one, and in vivo exposure to a cue that triggers the obsession, such as holding a knife, would then be followed by exposure to the obsession of stabbing a loved one while holding a knife. Interoceptive exposure can also be incorporated into in vivo or imaginal exposure. For example, a client with social anxiety may run in place to elevate her heart rate prior to delivering a speech.

Reinforced extinction—“Face your fear.” This strategy involves occasionally including aversive or deliberately negative outcomes during an exposure. Examples include adding social rejection in exposures to social situations or deliberately inducing a panic attack. In these examples, the exposure may not only enhance learning by heightening the salience of the exposure, but it may offer the client the opportunity to learn new coping strategies for negative outcomes. This strategy should not be used in situations in which a negative outcome would be dangerous (e.g., you would not conduct an exposure to a car accident).

Variability—“Vary it up.” Including variability in exposures enhances inhibitory learning during exposure and better represents the situations the client will face outside of therapy. Therapists can vary exposures in a number of ways, such as by including exposures to a wide range of diverse stimuli, varying the time and intensity of exposures, completing exposures in both familiar and unfamiliar places and at varying times of the day, and completing exposures from varying levels of the client’s hierarchy rather than steadily progressing from easier to more difficult exposures.

Remove safety behaviors—“Throw it out.” This strategy removes or prevents safety signals or safety behaviors, which are objects or behaviors that reduce or minimize fear or anxiety. Common safety signals include the presence of another person (including the therapist), medication, a cell phone, and food or drink; common safety behaviors include asking another person for reassurance, averting eye contact, overpreparing, escaping, and engaging in compulsive behaviors (e.g., hand washing or checking). Safety signals and behaviors can be detrimental to exposure therapy and can also lead to interference or distress with the signals and behaviors themselves (e.g., excessively calling one’s friend for reassurance may interfere with the friendship). Therefore, therapists should encourage clients to eliminate or gradually reduce the use of safety signals and behaviors.

Attentional focus—“Stay with it.” This strategy helps clients maintain attentional focus during exposure. Attending to exposure stimuli helps clients observe the outcome of the exposure and prevents them from being distracted and engaging in safety behaviors. The therapist might encourage clients to “stay with it” by directing their gaze during in vivo exposure or redirecting their descriptions during imaginal exposure.

Affect labeling—“Talk it out.” Affect labeling refers to using words to describe the content of an exposure (e.g., “ugly spider”) or one’s emotional response during exposure (e.g., “anxious” or “scared”). This strategy is based on social neuroscience research showing that linguistic processing can attenuate affective responses (Lieberman et al., 2007). To use this strategy, the therapist should encourage clients to label their emotion in the moment or describe the current object or situation without engaging in any strategies to alter or change their cognitions.

Mental reinstatement/retrieval cues—“Bring it back.” The final strategy uses reminders (also called retrieval cues) to help clients remember what they learned during previous exposures. This strategy is best used as a relapse-prevention skill rather than at the beginning of treatment because retrieval cues may become safety signals. As part of relapse prevention, the therapist may encourage clients to remind themselves of what they learned during exposure therapy each time they encounter a previously feared stimulus, or have them carry an item (e.g., a wristband) that serves as a tactile reminder.

Applications and Contraindications

Exposure is effective for treating most anxiety and fear-related problems. Therapists can evaluate whether exposure is needed by conducting a diagnostic assessment or a functional analysis to determine why the client is engaging in a certain problematic behavior. For example, the therapist might ask, “What types of situations trigger your fear or anxiety? What do you do when you experience anxiety or fear? What are you most concerned will happen if you do not engage in this behavior?” Overestimation of threat and engagement in safety or avoidance behaviors indicate that exposure is likely needed. Exposure is generally very safe and effective for addressing fear, anxiety, and associated maladaptive avoidance. However, there are certain cases in which exposure is contraindicated or must be used with caution:

• Recent suicidal or nonsuicidal self-injury. Little data exist on the use of exposure with highly suicidal or self-injuring clients, but delaying exposure until suicidality or self-injury has abated is recommended.
• Environmental danger. Exposures should not be conducted in situations where there is actual danger. For example, don’t conduct in vivo exposure with a client’s abusive partner.
• Interoceptive exposures with certain medical conditions. Some interoceptive exposures could aggravate certain medical conditions (e.g., seizure disorder). In such cases, the therapist should consult with the client’s medical doctor to adapt interoceptive exposures.

Tips for Success

As with any therapeutic strategy, problems can arise. Below are tips to help address the most common issues.

Redirect predictions about emotional responses. Commonly, clients will identify a predicted outcome about their emotional response during an exposure, such as “I will panic” or “I will get anxious.” In these cases, further probing may be required to elicit observable or behavioral predictions. For example, the therapist might ask, “What are you most concerned will happen if you panic?” If a client’s biggest concern is that the anxiety will be overwhelming, she may predict, for example, “I will be so anxious that I won’t be able to do anything.” An exposure designed to test this prediction would involve having the client complete some activity immediately following the exposure.

Avoid mind-reading predictions. Mind-reading predictions are predictions about what others will think. For example, a client completing a public-speaking exposure may predict, “The audience will notice that I am nervous,” or “They will think I’m stupid and incompetent.” To elicit a behavioral outcome, try one of the following:

• Probe for observable behaviors from others. Using the example above, the therapist might ask, “What specifically will the audience do if they think you are stupid and incompetent?”
• Ask for feedback from other individuals involved in the exposure. For example, following a public-speaking exposure, the client can ask the audience, “How did I sound? Did I seem nervous to you?” When feasible and appropriate, this approach can be helpful. However, it should not be overused, as asking for feedback can become a safety behavior.
• Use video feedback. Video feedback can be used to test out specific predictions about a client’s appearance (e.g., “My face will be bright red”) or performance (e.g., “I will stumble over my words”) during an exposure. This approach is most helpful for public-speaking exposures, but, as with asking for feedback, it should not be overused.

Do not let anxiety—yours or your client’s—interfere with exposure work. Therapists new to exposure may be uncomfortable with the notion of purposely provoking fear and anxiety during therapy, perhaps due to the belief that the client’s symptoms will worsen or that the client will drop out. Therapists who avoid their own emotions tend to avoid doing exposure (Scherr, Herbert, & Forman, 2015), at the expense of their clients’ improvement. Though exposure can be difficult, we know from decades of research that despite its temporarily anxiety- or fear-producing effects, exposure is very effective for providing long-term relief from anxiety and fear-based problems. The following suggestions may help prevent your client’s or your own anxiety from interfering with effective exposure treatment:

• Practice, practice, practice. As with any new behavior, conducting exposures requires practice. Practicing exposures that you are going to ask a client to complete prior to a session is one way to increase your comfort and skill with new exposures.
• Use therapist modeling. Modeling exposures for your client can be very helpful, especially in initial sessions.
• Reiterate rationale for exposure. If you get stuck, try to get back on track by discussing with the client the reasons for doing exposures.
• Work your way up. If an exposure is too difficult for a client, do not give up. Start with an easier exposure to help your client build self-efficacy, and then build up to the more challenging exposures.
• Watch out for safety signals and behaviors. These behaviors and signals can sometimes be hard to spot. If your client is reporting low fear levels during a difficult exposure, that may be a clue that the client is utilizing safety behaviors or signals.
• Keep in mind that anxiety means the exposure is working.

Do not overemphasize fear reduction. While fear reduction may occur during the course of exposure therapy, it is not the primary goal. Instead:

• Reinforce approach behaviors. Use encouragement and praise to reinforce approach behaviors and the completion of exposures, regardless of whether there was a change in fear or anxiety.
• Focus on actual outcomes. After completing an exposure, ask the client specific follow-up questions in order to highlight the actual outcomes of the exposure instead of the fear level.
• Keep in mind that fear reduction during exposure is not necessary for a client to improve. In fact, learning to tolerate fear and to act despite difficult emotions is likely a more important component of exposure than fear reduction.

Consider cultural adaptations of exposure. Using culturally informed approaches to adapt exposures for diverse populations can improve outcomes (e.g., see Pan, Huey, & Hernandez, 2011).

References

Arch, J. J., Eifert, G. H., Davies, C., Plumb Vilardaga, J. C., Rose, R. D., & Craske, M. G. (2012). Randomized clinical trial of cognitive behavioral therapy (CBT) versus acceptance and commitment therapy (ACT) for mixed anxiety disorders. Journal of Consulting and Clinical Psychology, 80(5), 750–765.

Bouton, M. E. (2004). Context and behavioral processes in extinction. Learning and Memory, 11(5), 485–494.

Craske, M. G., Kircanski, K., Zelikowsky, M., Mystkowski, J., Chowdhury, N., & Baker, A. (2008). Optimizing inhibitory learning during exposure therapy. Behaviour Research and Therapy, 46(1), 5–27.

Craske, M. G., Treanor, M., Conway, C. C., Zbozinek, T., & Vervliet, B. (2014). Maximizing exposure therapy: An inhibitory learning approach. Behaviour Research and Therapy, 58(1), 10–23.

Davies, C. D., Niles, A. N., Pittig, A., Arch, J. J., & Craske, M. G. (2015). Physiological and behavioral indices of emotion dysregulation as predictors of outcome from cognitive behavioral therapy and acceptance and commitment therapy for anxiety. Journal of Behavior Therapy and Experimental Psychiatry, 46, 35–43.

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Foa, E. B., Yadin, E., & Lichner, T. K. (2012). Exposure and response (ritual) prevention for obsessive compulsive disorder: Therapist guide (2nd ed.). Oxford: Oxford University Press.

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Pan, D., Huey Jr., S. J., & Hernandez, D. (2011). Culturally-adapted versus standard exposure treatment for phobic Asian Americans: Treatment efficacy, moderators, and predictors. Cultural Diversity and Ethnic Minority Psychology, 17(1), 11–22.

Scherr, S. R., Herbert, J. D., & Forman, E. M. (2015). The role of therapist experiential avoidance in predicting therapist preference for exposure treatment for OCD. Journal of Contextual Behavioral Science, 4(1), 21–29.

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