A Review of the Research Supporting (and Not Supporting) Inhibitory Learning Strategies

In my posts about exposure therapy, I’ve written about inhibitory learning theory a bit. I’ve particularly focused on how inhibitory learning theory has supplanted emotional processing theory (EPT) as the best supported model for exposure.

I recently came across a thorough review article that walks through the major inhibitory learning principles and recommended procedures—as well as some not explicitly tied to inhibitory learning –and assess the degree to which these principles and strategies are supported by research to date

The authors conclude:

Collectively, research support for exposure augmentation techniques aimed at optimizing inhibitory learning has fallen short of theoretical expectation in several respects. Though the literature strongly suggests that this theory provides a better mechanistic explanation for the results of exposure therapy than alternatives such as EPT (at least as originally proposed), findings regarding particular enhancement strategies have been quite inconsistent; even among studies in support of specific techniques, the majority of effects are modest at best.

As a summary can’t do justice to this article, I recommend you check it out yourself. If you have any interest in exposure therapy, it is essential reading.

Weisman, J.S, & Rodebaugh, T.L. (2018). Exposure therapy augmentation: A review and extension of techniques informed by an inhibitory learning approach. Clinical Psychology Review, 59, 41-51.

Here’s a link to the author’s ResearchGate page, where you can request a copy of the article.

An Overview of Emotional Processing Theory

An Overview of Emotional Processing Theory

NOTE: This post is part of a larger series of on the theory, practice, and research on exposure therapy. If you are interested in other posts in this series, you can find them here.

Twenty-five years ago, in an attempt to create a unifying theory that would explain the processes of and guide the use of exposure in the treatment of anxiety disorders, Foa and Kozak (1986) developed the emotional processing theory (aka, information processing theory). The emotional processing theory has since guided an enormous amount of research, particularly for posttraumatic stress disorder (PTSD). Dr. Foa drew from the theory in developing prolonged exposure, a landmark PTSD treatment and the gold standard approach to PTSD treatment.

Much of my experience with the emotional processing theory comes from my training in prolonged exposure. When I was originally trained in prolonged exposure, I had the impression that it was more on the behavioral side of cognitive behavioral therapy. However, in reading about the emotional processing theory in greater depth, I realized that, although prolonged exposure looks procedurally like behavior therapy, the theory behind it is more of a product of the cognitive revolution with its emphasis on the computer as a metaphor for the human mind.

According to the emotional processing theory, fear is activated through associative networks that include information about the feared stimulus, escape or avoidance responses to the feared stimulus, and the meaning of the fear (e.g., threat or danger). Fear becomes problematic when it is intense to a degree that it gets in the way of functioning, or when it persists even when there are no clear indications of danger. In these instances, there may be maladaptive or pathological fear structures. The theory holds that chronic avoidance (e.g., escape behavior, avoidance, dissociation) often leaves these maladaptive schemas in place, as people do not remain in a situation long enough for new learning to occur.

Emotional processing theory proposes that exposure can alter the relationships between the fear stimulus and these networks. For this to happen, the network must first be activated, and then new information must be encoded that is incompatible with what is in the fear network. This is accomplished through habituation. Staying in contact with a fear stimulus until there’s a reduction in anxiety allows for the encoding of new information that is incompatible with the fear stimulus (e.g., it’s not dangerous). For example, in someone with OCD, repeated exposure to an obsession while refraining from engaging in a particular ritual serves to disconfirm maladaptive beliefs about the importance of the ritual in keeping harm away.

I break this process down with greater detail below.

Fear Structures

We’ll start with fear structures. Originally proposed by Lang (1977), fear structures are cognitive networks of maladaptive thinking that become activated through fear or anxiety. For people with anxiety-related problems, there are two common maladaptive beliefs about the fear stimulus: 1. That anxiety or distress will escalate to the degree it becomes unmanageable (e.g., “I can’t handle this”); 2. The feared stimulus or their experience of anxiety will cause harm (e.g., “I’ll lose control” or “I’ll go crazy”). For example, someone with panic disorder might think, “I’m going to die” when they start to notice panic cues like shortness of breath.

The major problem, according to emotional processing theory, is that people with anxiety disorders usually engage in some form of escape or avoidance behaviors when they feel anxious. As a result, they don’t remain in contact with their anxiety long enough to disconfirm the fear structure. Over time, people continue to engage in disruptive behaviors (e.g., escape) whenever they experience fear. An unfortunate side effect of continued avoidance behavior is that people’s lives begin to constrict in order to avoid things that trigger the fear structures. Their lives become narrower and more confined (e.g., they stop leaving the house).

Disconfirming Fear Structures Through Habituation

The solution then, according to the emotional processing theory, is for people to stay with their anxiety long enough for it to reduce on its own. Research suggests that so long as we don’t actively feed anxiety through worry, it tends to go down on its own after about 45 minutes –what is called habituation to the feared stimulus. Through repeated habituation, they begin to learn that what they’re afraid will happen (e.g., “I’ll go crazy”) doesn’t occur, and/or that the feared consequences are less likely to occur or are milder than expected (e.g., “If people notice I’m anxious, they’ll laugh at me”).

Foa and Kozak (1986) suggested that exposure weakens associations and replaces maladaptive fear associations with more adaptive ones. However, this view was revised in Foa and McNally (1996), where the authors incorporated animal behavior models of exposure from the lab of Bouton. Bouton’s work suggests that exposure does not actually alter associations so much as creates new, competing associations. What this means is that following exposure, there may now be two associations: a pathological one and a non-pathological one. Ideally, the person begins engaging in behaviors that are more in accordance with the non-pathological association, strengthening it over time.

Here’s an example: A motor vehicle accident survivor develops a fear structure involving thoughts that all automobiles are extremely dangerous. As a consequence, he stops driving. The therapist might arrange a series of exposure exercises involving automobiles. The person might start by sitting in a parked car each day until his anxiety decreases. He may then drive very slowly on low traffic streets, working his way up to driving again. The man may retain the association that all automobiles are dangerous, but through exposure a competing association that harm is unlikely accompanies it. The man may then make choices in accordance with this second association (e.g., the choice to drive a car).

A Glimpse Into the Future of the Emotional Processing Theory

This is a brief sketch of the emotional processing theory. It has been hugely influential in guiding research on anxiety treatment, particular for posttraumatic stress disorder and obsessive-compulsive disorder. The application of the emotional processing theory to PTSD has led to a very successful treatment—prolonged exposure. However, treatments may be effective even if the theories guiding them are not entirely accurate.

As I’ve written in a previous post, the main area in which newer research has brought the emotional processing theory into question is its emphasis on habituation. There’s no reason to offer a complete retread of the post, but newer research suggests that it’s not necessary for someone’s anxiety to go down during exposure in order for him or her to benefit. Additionally, McNally (2007) argued that the concept of “fear structures” is vague, circular, and not supported by research. Dr. Craske at UCLA, in particular, has criticized the principles underlying the emotional processing theory (See Craske et al, 2008 for a summary of exposure research; Baker et al, 2010, for study from Craske’s lab questioning the usefulness of habituation in predicting treatment outcome).

In upcoming posts, I’ll be discussing newer research that challenges the emotional processing theory, and that offers glimpses into where our understanding of exposure may go.

For more information about Emotional Processing Theory

If you want to read more about emotional processing theory, here’s a good book:

 Pathological Anxiety, Emotional Processing in Etiology and Treatment (2005), by Barbara Rothbaum.

Or for the most widely used guide for Prolonged Exposure, the main therapy approach guided by emotional processing theory, see:

Prolonged Exposure Therapy for PTSD: Emotional Processing of Traumatic Experiences Therapist Guide (2007) by Edna Foa, et al.

UPCOMING TRAINING EVENTS

January 31, 2020, 8:30 am – 4:30 pm · Portland, OR · Details

This workshop is intended to be part 1 of a two day workshop, but can also be taken on its own. This workshop is useful for therapists who want an update on the current clinically applicable research on how shame functions, including an overview of how and when shame tends to be adaptive versus maladaptive. This day has two primary goals: 1. To provide an overview of research on shame and self-criticism that can guide clinical practice and 2. To allow therapists to experience the model from the inside-out so as to develop greater personal self-compassion and a deeper intuitive understanding of compassion-based intervention strategies. Read more

February 1, 2020, 8:30 am – 4:30 pm · Portland, OR · Details

This workshop is intended to be part 2 of a two day workshop, but can also be taken on its own. If you already have a thorough understanding of the functions of shame and a good understanding of Acceptance and Commitment Therapy, then it is you will probably be OK taking just the second day of this workshop. The workshop proceeds to discuss how ACT processes can be focused on addressing chronic and pervasive shame-based difficulties, with a particular focus on flexible perspective taking. Demonstrations of how to use perspective taking and compassion-fostering strategies with clients will be provided and attendees will also practice in small groups. An overview of chair work in the context of ACT will be provided. Read more

February 29, 2020, 9:00 am – 12:15 pm · Portland, OR · Details

Exposure is one of most the effective treatments for anxiety, trauma, and obsessive compulsive and related disorders (e.g., OCD, PTSD, panic disorder). A transdiagnostic intervention, exposure involves the repeated and systematic engagement with avoided stimuli that cause anxiety. Unfortunately, exposure remains underutilized by clinicians (e.g., Scherr, Herbert, & Forman, 2015), mostly due to misunderstandings of how exposure works and perceived difficulty of using it with clients. This half-day workshop will address these gaps by drawing from research on enhancing clinician understanding of and ways to overcome barriers to delivering exposure therapy (Farrell et al., 2016). Using didactics, role-play, and experiential exercises, participants will learn flexible application of exposure for a variety of clinical targets. Read more

April 17 and 18, 2020, 9:15 am – 5:00 pm · Portland, OR · Details

Do you ever “get stuck” as a therapist? Do some of your clients press your “hot buttons”? Do you ever find yourself struggling and thinking about “what do I do next” or feeling anxious, scared or stressed in therapy? In this workshop we will work on clarifying your therapist values and defining what is “difficult” about “difficult” clients. Through discussions, demonstrations and roleplays we will then work on these difficult clients and look at the processes from a compassionate ACT perspective. Read more