Acceptance and commitment therapy
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Acceptance and commitment therapy (ACT, typically pronounced as the word "act") is a form of clinical behavior analysis (CBA) used in psychotherapy. It is an empirically-based psychological intervention that uses acceptance and mindfulness strategies mixed in different ways with commitment and behavior-change strategies, to increase psychological flexibility. The approach was originally called comprehensive distancing. It was developed in the late 1980s by Steven C. Hayes, Kelly G. Wilson, and Kirk Strosahl.
The objective is not happiness; rather, it is to be present with what life brings us and to "move toward valued behavior". Noam Shpancer describes acceptance and commitment therapy as getting to know unpleasant feelings, then learning not to act upon them, and to not avoid situations where they are invoked. Its therapeutic effect is according to him a positive spiral where feeling better leads to a better understanding of the truth.
ACT is developed within a pragmatic philosophy called functional contextualism. ACT is based on relational frame theory (RFT), a comprehensive theory of language and cognition that is an offshoot of behavior analysis. ACT differs from traditional cognitive behavioral therapy (CBT) in that rather than trying to teach people to better control their thoughts, feelings, sensations, memories and other private events, ACT teaches them to "just notice," accept, and embrace their private events, especially previously unwanted ones.
ACT helps the individual get in contact with a transcendent sense of self known as "self-as-context"—the you that is always there observing and experiencing and yet distinct from one's thoughts, feelings, sensations, and memories. ACT aims to help the individual clarify their personal values and to take action on them, bringing more vitality and meaning to their life in the process, increasing their psychological flexibility.
While Western psychology has typically operated under the "healthy normality" assumption which states that by their nature, humans are psychologically healthy, ACT assumes, rather, that psychological processes of a normal human mind are often destructive. The core conception of ACT is that psychological suffering is usually caused by experiential avoidance, cognitive entanglement, and resulting psychological rigidity that leads to a failure to take needed behavioral steps in accord with core values. As a simple way to summarize the model, ACT views the core of many problems to be due to the concepts represented in the acronym, FEAR:
- Fusion with your thoughts
- Evaluation of experience
- Avoidance of your experience
- Reason-giving for your behavior
And the healthy alternative is to ACT:
- Accept your reactions and be present
- Choose a valued direction
- Take action
ACT commonly employs six core principles to help clients develop psychological flexibility:
- Cognitive defusion: Learning methods to reduce the tendency to reify thoughts, images, emotions, and memories.
- Acceptance: Allowing thoughts to come and go without struggling with them.
- Contact with the present moment: Awareness of the here and now, experienced with openness, interest, and receptiveness.
- Observing the self: Accessing a transcendent sense of self, a continuity of consciousness which is unchanging.
- Values: Discovering what is most important to one's true self.
- Committed action: Setting goals according to values and carrying them out responsibly.
As of 2015, there have been four meta-analyses of ACT efficacy. A 2008 meta-analysis concluded that research quality of ACT studies was too poor for it to be considered an empirically supported treatment. A 2009 meta-analysis found that ACT was more effective than placebo and "treatment as usual" for most problems, with the exception of anxiety and depression, but no more effective than traditional therapies like cognitive behavioral therapy (CBT). A 2012 meta-analysis reported that ACT outperformed CBT, except for depression and anxiety. A 2015 meta-analysis found that ACT was more effective than placebo and "treatment as usual", and as effective as traditional treatments like CBT for depression, anxiety disorders, addiction and somatic health problems. The authors suggested that the CBT comparison of the previous 2012 meta-analysis may have been compromised by the inclusion of nonrandomized trials with small sample sizes. They also noted that research methodologies had improved since the studies described in the 2008 meta-analysis.
ACT had, as of October 2006, been evaluated in about 30 controlled time series studies or randomized clinical trials for a variety of client problems. As of 2011 that number had approximately doubled and new controlled studies were regularly being published. Overall, when compared to other treatments designed to be helpful, the effect size for ACT is a Cohen's d of around 0.6 which is considered a medium effect size. In some studies, ACT has been found to exceed the efficacy of 'gold-standard' treatments; in others, it has been found to be equally effective to standard treatments; and, in several others, it has been found to be less effective than existing standards.
As compared to treatments that are already known to be effective, the effect size so far is about .3, which is small. Across the whole empirical clinical psychology literature the average effect size for such comparisons approaches zero, however. All of these comparisons and their effect sizes need to be viewed with caution, because many of the trials are unfunded and are based on a relatively small number of patients; and in some cases might be contaminated by the allegiance effect.
A large and well done trial by a major CBT research team on mixed anxiety disorders that showed superiority of ACT to gold standard CBT on the primary outcome measure has recently appeared however and in that study allegiance effects should have worked in the opposite direction, suggesting that at least some of the effects in favor of ACT are replicable by teams that are skeptical of this approach
In recent years, larger and better controlled trials have been conducted and the number of areas to which it has been successfully applied is growing. ACT is considered an empirically validated treatment by the American Psychological Association, with the status of "Modest Research Support" in depression and "Strong Research Support" in chronic pain, with several others specific areas such as psychosis and work site stress currently under review. ACT is also listed as evidence-based by the Substance Abuse and Mental Health Services Administration of the United States federal government which has examined randomized trials for ACT in the areas of psychosis, work site stress, and obsessive compulsive disorder, including depression outcomes.
ACT is still relatively new in the development of its research base with the randomized trials beginning in earnest only after the 1999 publication of the original book on ACT. ACT has shown preliminary research evidence of effectiveness in randomized trials for a variety of problems including chronic pain, addictions, smoking cessation, depression, anxiety, psychosis, workplace stress, diabetes management, weight management, epilepsy control, self-harm, body dissatisfaction, eating disorders, burn out, and several other areas. ACT has more recently been applied to children, adolescents and trainees,.
Mediational analyses have provided evidence for the possible causal role of key ACT processes, including acceptance, defusion, and values, in producing beneficial clinical outcomes. Correlational evidence has also found that absence of these processes predicts many forms of psychopathology. A recent meta-analysis showed that ACT processes, on average, account for 16–29% of the variance in psychopathology (general mental health, depression, anxiety) at baseline, depending on the measure, using correlational methods.:12–13 A recent meta-analysis of 68 laboratory-based studies on ACT components has also provided support for the link between psychological flexibility concepts and specific components.
In New Zealand, the Department of Psychology at the University of Waikato, in conjunction with the local DHB approved research, to evaluate the effectiveness of ACT therapy (through self-help books) for people with chronic pain. The sample size was twenty-four with eligibility being reading comprehensive ability, no psychiatric disorder, stable medication and no childhood history of trauma.
The method was randomised two group study conducted over a six-week period with some participants required to read the self-help book and complete exercises. Pre-intervention and post-intervention questionnaires for acceptance, values illness, quality of life, satisfaction with life, depression, anxiety, and pain were completed. Interestingly, data demonstrated that those who completed the intervention evidenced statistically significant improvements (with large effect sizes) for acceptance, satisfaction with life and quality of life. Medium effect sizes were also established for enhancement in pain ratings. The findings maintained the proposition that utilising the self-help book, with minimal therapist contact adds value to the well-being of people who encounter chronic pain.
ACT, Dialectical Behavior Therapy, Functional Analytic Psychotherapy, Mindfulness-based Cognitive Therapy and other acceptance and mindfulness based approaches are commonly grouped under the name The Third Wave of Behavior Therapy, with the first wave commencing in the 1920s that related to Pavlov’s classical (respondent) and operant conditioning that was correlated to reinforcing consequences. The second wave emerged in the 1970s and included cognition in the form of irrational beliefs, dysfunctional attitudes or depressogenic attributions. In the late 1980s empirical limitations and philosophical misgivings of the second wave gave rise to Steven Hayes ACT theory which modified the focus of abnormal behaviour away from the content or form towards the context in which it occurs. ACT research has suggested that many of the emotional defences individuals use with conviction, to solve disorders, actually entangle humans into suffering.
Grounded in an empirical, principle-focused approach, the third wave of behavioral and cognitive therapy is particularly sensitive to the context and functions of psychological phenomena, not just their form, and thus tends to emphasize contextual and experiential change strategies in addition to more direct and didactic ones. These treatments tend to seek the construction of broad, flexible and effective repertoires over an eliminative approach to narrowly defined problems, and to emphasize the relevance of the issues they examine for clinicians as well as clients. The third wave reformulates and synthesizes previous generations of behavioral and cognitive therapy and carries them forward into questions, issues, and domains previously addressed primarily by other traditions, in hopes of improving both understanding and outcomes.
ACT has also been adapted to create a non-therapy version of the same processes called Acceptance and Commitment Training. This training process, oriented towards the development of mindfulness, acceptance, and values skills in non-clinical settings such as businesses or schools, has also been investigated in a handful of research studies with good preliminary results. This is somewhat similar to the awareness–management movement in business training programs, where mindfulness and cognitive-shifting techniques are employed.
The emphasis of ACT on ongoing present moment awareness, valued directions and committed action is similar to other psycho-therapeutic approaches that, unlike ACT, are not as focused on outcome research or consciously linked to a basic science program, including more humanistic or constructivist approaches such as Gestalt Therapy, Morita Therapy and Voice Dialogue, IFS and others.
Wilson, Hayes & Byrd explore at length the compatibilities between ACT and the 12-step treatment of addictions and argue that, unlike most other psychotherapies, both approaches can be implicitly or explicitly integrated due to their broad commonalities. Both approaches endorse acceptance as an alternative to unproductive control. ACT emphasizes the hopelessness of relying on ineffectual strategies to control private experience, similarly the 12-step approach emphasizes the acceptance of powerlessness over addiction. Both approaches encourage a broad life-reorientation, rather than a narrow focus on the elimination of substance use, and both place great value on the long-term project of building of a meaningful life aligned with the clients' values. ACT and 12-step both encourage the pragmatic utility of cultivating a transcendent sense of self (higher power) within an unconventional, individualized spirituality. Finally they both openly accept the paradox that acceptance is a necessary condition for change and both encourage a playful awareness of the limitations of human thinking.
Some published studies in clinical psychology have concluded that ACT is no different from other interventions. A meta-analysis by Öst concluded that ACT did not qualify as an "empirically supported treatment," that the research methodology for ACT was less stringent than cognitive behavioral therapy, and that the mean effect size was moderate. Supporters of ACT have challenged those conclusions and discussed the limitations of Öst's review.
Several concerns both theoretical and empirical have arisen in response to the ascendency of ACT. One major theoretical concern is that the primary authors of ACT and the corresponding theories of human behavior, relational frame theory (RFT) and functional contextualism (FC) recommend their approach as the proverbial holy grail of psychological therapies:
A discipline based purely on statements that are high in precision, but with narrow applicability, becomes increasingly disorganized and incoherent... Without an emphasis on philosophy and theory no other result is possible, because it is difficult to assimilate the mountain of seemingly disconnected bits of information that science-as-technology presents. The field becomes an incoherent mass, impossible to master and impossible to teach. In addition, the shallow level of analysis means that other areas of science cannot be related to clinical techniques. A hole in the fabric of science opens that cannot be filled. The solution to this incoherence is the organizing force of well thought out theory and philosophy.
“In 1988, Hayes and colleagues stated that functional contextualism strips ‘needless mechanism and needless philosophical inconsistencies’ from radical behaviorism and 'puts behavior analysts' hands on the tiller of their philosophical vessel. It may steer better from there.” 
There is concern that the authors of ACT and RFT have been overly "fused" with the notion of the power of theory and philosophy to guide practice onto the most effective path and have neglected some of the fundamental principles of an empirical science. Those principles dictate that theory be validated by empirical data. One such attempt is detailed in the meta-analysis published by Francisco Ruiz in 2012. In this meta-analysis of 16 studies comparing ACT to standard CBT, ACT failed to separate from CBT on effect sizes for depression, anxiety or quality of life. The author did find separation between ACT and CBT on the "primary outcome" – a heterogeneous class of 14 separate outcome measures that were aggregated into the effect size analysis. This analysis however is limited by the highly heterogeneous nature of the outcome variables used in the analysis, which has the tendency to increase the number needed to treat (NNT) to replicate the effect size reported. More limited measures, such as depression, anxiety and quality of life decrease the NNT, making the analysis more clinically relevant, and on these measures ACT did not outperform CBT.
The Association for Contextual Behavioral Science is committed to research and development in the area of ACT, RFT, and contextual behavioral science more generally. As of mid-2015 it had over 7,500 members worldwide, about half outside of the United States. It holds annual "world conference" meetings: The 13th will be held in Berlin in July 2015; the 14th will be held in Seattle in July 2016.
The Association for Behavior Analysis International (ABAI) has a special interest group for practitioner issues, behavioral counseling, and clinical behavior analysis ABA:I. ABAI has larger special interest groups for autism and behavioral medicine. ABAI serves as the core intellectual home for behavior analysts. ABAI sponsors three conferences/year—one multi-track in the U.S., one specific to Autism and one international.
The Association for Behavioral and Cognitive Therapies (ABCT) also has an interest group in behavior analysis, which focuses on clinical behavior analysis. ACT work is commonly presented at ABCT and other mainstream CBT organizations.
The British Association for Behavioural and Cognitive Psychotherapies (BABCP) has a large special interest group in ACT, with over 1,200 members.
Doctoral-level behavior analysts who are psychologists belong to the American Psychological Association's division 25—Behavior analysis. APA offers a diplomate[clarification needed] in behavioral psychology.
The World Association for Behavior Analysis offers certification in behavior therapy which covers knowledge of ACT.
- Behavior therapy
- Behavioral psychotherapy
- Clinical behavior analysis
- Experiential avoidance
- Morita therapy
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- Hayes, Steven C.; Spencer Smith (2005). Get Out of Your Mind and Into Your Life: The New Acceptance and Commitment Therapy. New Harbinger Publications. ISBN 1-57224-425-9.
- Hayes, Steven C.; Kirk D. Strosahl (2004). A Practical Guide to Acceptance and Commitment Therapy. Springer. ISBN 0-387-23367-9.
- Hayes, Steven C.; Kirk D. Strosahl; Kelly G. Wilson (2003). Acceptance and Commitment Therapy: An Experiential Approach to Behavior Change. The Guilford Press. ISBN 1-57230-955-5.
- Eifert, Georg H.; John P. Forsyth (2005). Acceptance and Commitment Therapy for Anxiety Disorders: A Practitioner's Treatment Guide to Using Mindfulness, Acceptance, and Value-Guide Behavior Change Strategies. Oakland, CA: New Harbinger. ISBN 1-57224-427-5.
- Forsyth, John P.; Georg H. Eifert (2007). The Mindfulness and Acceptance Workbook for Anxiety: A Guide to Breaking Free From Anxiety, Phobias, and Worry Using Acceptance and Commitment Therapy. Oakland, CA: New Harbinger. ISBN 1-57224-499-2.
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- Contextualpsychology.org – Home for the Association for Contextual Behavioral Science, a professional organization dedicated to ACT, RFT, and functional contextualism. Also helpful for training opportunities for professionals interested in ACT and RFT. Most ACT workshops worldwide are listed here.
- Steven C Hayes – One of ACT's main theorists, Dr. Hayes' is at the University of Nevada. Information can also be found at his website
- ACT Workshops in the UK
- An Introduction to ACT
- Introduction to ACT and other mindfulness therapies
- An Introduction to Relational Frame Theory Online Tutorial
-  - GENDRON Benedicte, (2012), Le développement du capital émotionnel au service du bien-être à partir de l'approche de la thérapie de l'acceptation et de l'engagement -ACT-, Chapitre 21, in Ch. Martin-Krumm, C. Tarquinio (dir.), Traité de psychologie positive, De Boeck. :
- The ACT Formula for Self-Compassion - First published on the Association for Contextual Behavioral Science (ACBS) ListServ - By Dr. Russ Harris, MD and Dr. Emily Blake, PhD.