Acceptance and Commitment Therapy (ACT) was developed in the context of a new wave of behavior theories in order for patients to be able to have the option of a treatment that targeted not just the cause of the problem, but the context. ACT seeks to broaden the approach people take to problems and create a flexible skill set with which they can face new ones (Hayes, Luoma, Bond, Masuda, & Lillis, 2006).
ACT stems from relational frame theory which stresses the contextual development of cognition and language (Hayes et al., 2006). Due to the contextual development of these processes, trying to eliminate the learned responses is not an ideal solution, therefore, instead of focusing on the content of these networks, it may make sense to shift to look at the function they serve. The interactions of these networks with the rewards they produce leads people to be unable to change their behavior in accordance with their long term values, which is termed psychological inflexibility in ACT (Hayes et al., 2006).
ACT posits that the psychological inflexibility arises due to a combination of experiential avoidance, cognitive fusion, dominance of the conceptualized past and feared future, a lack of values clarity, inaction, impulsivity or avoidant persistence, and attachment to conceptualized self (Hayes et al., 2006). In this model, cognitive fusion is defined as the incorrect regulation of behavior by verbal processes and it serves to support the experiential avoidance (Hayes et al., 2006).
Ultimately, these processes feed off of one another and force behavior that is counterproductive to one’s long term goals in favor of immediate rewards, appearing better, and defense of one’s conceptualized self (Hayes et al., 2006). Additionally, this psychological inflexibility can reduce the opportunity for one to gain other outside rewards that may allow the individual to move closer to their long-term goals (Bluett, Homan, Morrison, Levin, & Twohig, 2014).
The six core processes that ACT targets, which should together increase psychological flexibility are: acceptance, cognitive defusion, being present, self as context, values, and committed action. Increasing these should allow people to flexibly interact with the context and have their actions then align better with their values (Bluett et al., 2014). Acceptance, the dialectic of experiential avoidance, refers to the principle of actively welcoming the events as they come without changing them (Hayes et al., 2006). Cognitive defusion seeks to change the function of the thought as opposed to the content, as described previously changing overly learned behaviors is difficult and may be counterproductive, therefore, changing the undesirable function can change the interaction between one and the thought. Skills are taught to improve cognitive defusion, which allow one to observe the negative thoughts and detach from them as opposed to being overly involved with them (Hayes et al., 2006).
Being present is the skill of being actively aware of one’s actions and environment and creating nonjudgmental contact with external events as well as controlled behavior over one’s actions (Hayes et al., 2006). Self as context is cultivated by mindfulness exercises that allow one to be aware of one’s experiences without attachment to them, and to view the self as a context in itself (Hayes et al., 2006). Values are selected purposeful actions that each individual chooses which they hope to attain, and in ACT these life values are selected and worked towards. Committed action is the client’s need to pledge to working towards the valued actions by carrying out effective behaviors, and this is improved with behavioral techniques, exposures, and procurement of skills (Hayes et al., 2006).
The current knowledge on the evidence for ACT applied to a variety of disorders, from somatic to psychiatric, and the shortcomings with ACT for each of these disorders are reviewed. Additionally, areas for future research and improvement are highlighted. ACT was developed out of a need for a treatment that focused on changing the context of thoughts and behaviors, rather than the content, in order to allow for more committed behavior towards one’s personal goals. Therefore, in addition to the findings of the efficacy of ACT for the disorders, it is critically examined whether that theory aligns with the goals of treatment for the following disorders.
Current Knowledge on the Evidence-Base for the Treatment
Pain
ACT as a treatment for chronic pain, as per Division 12, has the most support out of the disorders that ACT has been tested to treat (Division 12 APA, n.d.-a). When taking into account how the ACT framework could be applied to chronic pain this is unsurprising, as the goals of ACT and those with chronic pain relief appear to be consistent. Given that removal of chronic pain is an unrealistic goal, as combinations of medicines and therapeutic treatments have never been able to completely eliminate chronic pain that people suffer, the outcome measures of chronic pain treatment studies should be to reduce pain interference and improve functioning despite the pain (M. M. Veehof et al., 2016).
Improving functioning is key because chronic pain leads to emotional, physical, and social functional impairments. ACT’s theoretical base of acceptance and focus on achieving the valued goals align with then the goals of reducing pain interference, accepting the pain, and improving functioning, or reaching the valued goal (Hann & McCracken, 2014; Kemani et al., 2015; Simister et al., 2018; M. M. Veehof et al., 2016).
Many RCTs and several meta-analyses have assessed the efficacy of ACT for chronic pain. It is important to assess for both change in the ACT condition (measured by pre to post treatment and follow-up measures), as well as compare ACT to other treatments.
The majority of studies find that those in the ACT condition improve on a variety of outcome measures from the beginning of treatment to post treatment, with some studies finding improvements (range from small to moderate) in pain intensity, depression, anxiety/stress, and quality of life.
Depression
ACT has been studied in its use to treat depression both in the original format of face to face ACT, as well as in an online version. It appears that ACT does reduce depressive symptoms over time in both formats (d=0.54-0.92 ) (Carlbring et al., 2013; Churchill et al., 2013; Hacker et al., 2016; Lappalainen et al., 2014; Lappalainen, Langrial, Oinas-Kukkonen, Tolvanen, & Lappalainen, 2015; Ost, 2014; Pots et al., 2016). However, while ACT outperforms some wait-list control groups or treatment as usual groups, it is unclear if it is fair to truly compare these to two treatments and ACT does not appear to perform better in reducing depression than cognitive therapies (Churchill et al., 2013; Hacker et al., 2016; Ost, 2014; Pots et al., 2016).
Anxiety
Various studies look ACT as a treatment for anxiety, and the various anxiety-related disorders (of the time) including generalized anxiety disorder (GAD), social anxiety disorder (SAD), panic disorder, post-traumatic stress disorder (PTSD), obsessive compulsive disorder (OCD), and general work stress. The theory of ACT adapted to treating anxiety argues that the psychological flexibility gained from ACT would allow flexible interaction with the anxiety to the point where it was tolerable and would not interfere with moving towards one’s valued goals (Bluett et al., 2014). The outcome measure often used for ACT, the Acceptance and Action Questionnaire (AAQ), appears to be more correlated with outcome measures for GAD and social phobia rather than outcomes of panic or agoraphobia, and likewise the results of several studies found that ACT may be better equipped to improve symptoms of GAD over other anxiety disorders (Bluett et al., 2014; Ost, 2014).
Similar to for previous disorders, ACT appears to be moderately effective in reducing anxiety symptoms from pre-to post treatment (d=0.45-0.95) (Bluett et al., 2014; Hacker et al., 2016; Ost, 2014). However, when looking at efficacy as better than the control group for ACT for anxiety disorders, most studies find that ACT is more effective than the wait list control, but not more effective than CBT for anxiety (Bluett et al., 2014; Hacker et al., 2016; Ost, 2014). SACT for work stress appears to improve symptoms of stress over time, however, it has not been compared to a rigorous control condition (Ost, 2014). Similarly for OCD, ACT has garnered modest research support in being effective, but not more so than CBT (Bluett et al., 2014; Hacker et al., 2016; Ost, 2014).
For SAD, ACT appears to improve symptoms over time, and not perform significantly differently than CBT (Bluett et al., 2014; Ost, 2014). ACT appears to be even more experimental for disorders such as PTSD, where case studies and single subject designs appear to be utilized (Bluett et al., 2014). However, ACT has been proposed as a beneficial treatment for PTSD in theory in order to create a collaborative setting for the patient and ensure that the patient does not feel that the trauma is being pathologies (McLean & Follette, 2016). For panic disorder and specific phobia it appears that ACT is leading to improvements, but lack of rigorous studies leads it to be an experimental treatment for these disorders at this time (Bluett et al., 2014).
Psychotic Symptoms
There are a dearth of rigorous studies looking at ACT for psychotic symptoms, however, feasibility studies have indicated that ACT may lead to reductions in psychotic symptoms, and perhaps reduced hospitalizations (Bach, Hayes, & Gallop, 2012; Gaudiano & Herbert, 2006; Ost, 2014; White et al., 2011).
ACT for the treatment of borderline personality disorder has garnered little research, however, preliminary studies indicate that it may be better at reducing symptoms than treatment as usual conditions (Ost, 2014). Unfortunately, these results are difficult to attribute solely to ACT given that ACT in these studies was combined with other behavioral therapy and emotion focused therapy techniques.
ACT has also been utilized in some studies on trichotillomania, epilepsy, tinnitus, obesity, diabetes, and substance abuse. It is not possible to definitively come to a conclusion about the efficacy of ACT for these disorders given the lack of published research, however it appears that ACT combined with additional elements of other treatments for some of these disorders such as trichotillomania, epilepsy, tinnitus, obesity, drug abuse, and nicotine dependence leads to decreases in symptoms and improvements. However, these improvements seen with ACT for these disorders do not appear better than the standard of care or treatment as usual (Bricker, Mull, et al., 2014; Bricker, Bush, Zbikowski, Mercer, & Heffner, 2014; Ost, 2014; Stotts et al., 2012; Weineland, Hayes, & Dahl, 2012).
Limitations & Discussion
ACT is considered efficacious for several disorders including chronic pain, depression and some anxiety disorders, though often not more effective than the current gold-standard of treatment (A-Tjak et al., 2015). Additionally, there are areas for improvement in ACT research moving forward in order to address the problems with the current state of affairs for ACT research. The majority of the studies to date compare ACT to wait-list control or treatment as usual groups. The problem with using treatment as usual groups in particular, is the lack of consistency of what treatment as usual entails across studies as well as even within studies between participants.
Furthermore, several reviews have shown that these treatment as usual conditions are in therapy for less hours on average than those in the ACT group, calling into question whether these two groups are actually comparable (Churchill et al., 2013; Ost, 2014). The treatment as usual conditions also vary in terms of whether or not they can actually be considered treatment as usual (Bluett et al., 2014; Churchill et al., 2013; Ost, 2014; Pots et al., 2016).
The variability among the research studies conducted in terms of checks for treatment adherence, therapist competence, and diagnosis reliability is huge, indicating that the quality of studies being assessed has a large range and must be noted (A-Tjak et al., 2015; Hacker et al., 2016; Ost, 2014; M. M. Veehof et al., 2016). In order for ACT to be properly administered, the therapists need to be trained according to the theoretical framework intended, and quality checks should be conducted. However, the methodological rigor of the studies on ACT could be poor in part due to funding differences for ACT versus CBT (Gaudiano, 2009).
Aside from the methodological quality of the studies that have been conducted on ACT, several other limitations of ACT as it stands currently exist. The populations that have been the main focus of ACT to date for chronic pain, for which it has the largest evidence base, are adult populations. Only more recently have studies begun to test the efficacy of ACT in pediatric populations (Pielech, Vowles, & Wicksell, 2017; M. M. Veehof et al., 2016).
ACT also needs to be tested for efficacy in different languages, and different cultures. Initial data from the studies that do report the demographics of their samples indicate ACT could have cross-cultural competency, however it is an area that warrants further research(Woidneck, Pratt, Gundy, Nelson, & Twohig, 2012).
Novel ways of adapting ACT are being developed and should continue, given ACT’s efficacy for some treatments. The development of on-line versions of ACT are sure to benefit the future of mobile health and the use of ACT for disorders such as Erectile Dysfunction management will allow ACT to help to bring the field of psychology further into psychical health management (Carlbring et al., 2013; Lappalainen et al., 2014, 2015; Nelson et al., 2015)
ACT appears to be most effective in its treatment of chronic pain, and it does appear to significantly reduce symptoms of other disorders including anxiety and depression, indicating general effects on well-being. However, further research needs to delineate whether it is truly more beneficial than current standards of treatment (A-Tjak et al., 2015; Churchill et al., 2013; Hann & McCracken, 2014). Additionally, research should focus on the components of ACT that truly make it unique and ensure to measure outcome variables directly related to those components which need to be correlated with the relevant outcomes for those particular disorders.
Individual differences are now being recognized more so than ever in the current health context, and research has shown that certain characteristics may make people more likely to respond to ACT over CBT, or be more likely to withdraw from therapy given either treatment (Niles, Wolitzky-Taylor, Arch, & Craske, 2017). Therefore, as ACT has efficacy for a variety of disorders, it is vital that researchers consider it for a wide range of diagnoses, where perhaps other treatments are failing, or individual participants do not respond to treatment as usual. Given its efficacy in particular for pain management, it should be further considered in the context of palliative care, and disorders where pain management is included.
