The common thread running through research conducted by members of the CBS Lab is an attempt to better understand the roles that languaging and verbal behavior play in the initiation, maintenance, and alleviation of human suffering from a functional contextualistic perspective. Some of the research projects are more basic in nature, while others are more explicitly applied and clinical in their focus. More basic research projects focus on the development of both self-report and behavioral ways of assessing processes that contribute to psychological flexibility/rigidity as well as experimentally manipulating these same processes in impacting analogues of clinical forms of human suffering, such as anxiety and mood disorders. More applied research projects compare the clinical outcomes and related processes associated with traditional cognitive-behavioral interventions in treatment of depression versus ACT and related acceptance and mindfulness-based approaches.

Current Projects

Current projects include (a) the development and validation of a quantitative measure of self-as-context, (b) the development of dissociative symptom-inducing interoceptive exercises and tasks, (e) an evaluation of how experiential approach moderates response to a positive mood-induction procedure, (d) a comparison of mood-enhancing versus value-congruent behavioral activation in treatment of depression, (f) a comparison of cognitive restructuring versus defusion in targeting different types of depressing thoughts, and (g) an evaluation of the role of client treatment preference in comparing more traditional CBT versus ACT in alleviation of spider fear.


In press

  1. Zettle. R. D. (in press). Depression. In P. L. dos Santos, S. Carvalho, J. P. Gouveia, M. da Silva Oliveira, & J. Pistorello (Eds). International ACT handbook. Novo Hamburgo, Brazil: Sinopsys Editoria.
  2. Zettle, R. D., & Gird, S. R. (in press). Acceptance and mindfulness-based interventions. In R. J. DeRubeis & D. R. Strunk (Eds.), Oxford handbook of mood disorders (pp. 435-446). Oxford, United Kingdom: Oxford University Press.

Selected Publications

  1. Cathey, A. J., & Zettle, R. D. (2016). The development of novel interoceptive exposure methods for inducing derealization and depersonalization symptoms. Journal of Cognitive Psychotherapy, 30, 223-234.
  2. Swails, J. A., Zettle, R. D., Burdsal, C. A., & Snyder, J. J. (2016). The Experiential Approach Scale: Development and preliminary psychometric properties. The Psychological Record, 66, 527-545.
  3. Zettle, R. D. (2016). The self in acceptance and commitment therapy. In M. Kyrios, R. Moulding, G. Doron, S. S. Bhar, M. Nedeljkovic, & M. Mikulincer, The self in understanding and treating psychological disorders (pp. 50-58). Cambridge, United Kingdom: Cambridge University Press.
  4. Zettle, R.D., Hayes, S. C., Holmes-Barnes, D., & Biglan, A. (Eds.). (2016). The Wiley handbook of contextual behavioral science. Chichester, United Kingdom: Wiley.
  5. Zettle, R. D. (2016). Acceptance and commitment theory of depression. In A. Wells & P. L. Fisher (Eds.), Treating depression: MCT, CBT, and third wave therapies (pp. 169-193). Chichester, United Kingdom: Wiley.
  6. Zettle, R. D. (2015). Acceptance and commitment therapy for depression. Current Opinion in Psychology, 2, 65-69.
  7. Carrasquillo, N., & Zettle, R. D. (2014). Comparing a brief self-as-context exercise to control-based and attention-placebo protocols in coping with induced pain. The Psychological Record, 64, 659-669.
  8. Zettle, R. D., Barner, S. L., Gird, S. R., Boone, L. T., Renollet, D. L., & Burdsal, C. A. (2012). A psychological biathlon: The relationship between level of experiential avoidance and perseverance on two challenging tasks. The Psychological Record, 62, 433-445.
  9. Zettle, R. D., Rains, J. C., & Hayes, S. C. (2011). Processes of change in acceptance and commitment therapy and cognitive therapy for depression: A mediational reanalysis of Zettle and Rains (1989). Behavior Modification, 35, 265-283.
  10. Wagener, A. L., & Zettle, R. D. (2011). Targeting fear of spiders with control-, acceptance-, and information-based approaches. The Psychological Record, 61, 77-92.


  1. Zettle, R. D. (2016, June). The self in acceptance and commitment therapy. Frontiers Keynote address presented at the 8th World Congress of Behavioral and Cognitive Therapies, Melbourne, Australia.
  2. Cathey, A., Vilardaga, R., Swails, J., & Zettle, R. D. (2016, June). Using ecological momentary assessment to examine impact of self-regulation choice on affect. In J. Rizo (Chair), Ecological momentary assessments (EMA) to measure ACT processes and behavioral health across populations. Symposium presented at the ACBS Annual Conference 14, Seattle, WA.
  3. Swails, J., & Zettle, R. D. (2016, June). Experiential approach: Efforts to control positive emotions. Ignite presentation at the ACBS Annual Conference 14, Seattle, WA.
  4. Zettle, R. D. (2015, February). Experiential control as the clinical behavior analyst views it. Invited address presented at the California Association for Behavior Analysis Conference, San Diego, CA.
  5. Zettle, R. D. (2013, April). Acceptance and commitment therapy and the unmotivated client. Presented at the Second International Conference of Metacognitive Therapy, Manchester, England.


Dr. Robert D. Zettle, Professor
411 Jabara Hall

Graduate Students:

Nakisha Carrasquillo, M. A.
439 Jabara Hall
Angela Cathey, M. A.
404 Jabara Hall
Suzanne Gird, M. A.
439 Jabara Hall
Angie Hardage-Bundy, M. A.
439 Jabara Hall
Sarah Staats
413 Jabara Hall
Jeff Swails
404 Jabara Hall

Contextual Behavioral Science Lab, 2013

Back row: Jeff Swails, Angie Hardage-Bundy, Nakisha Carrasquillo,
Dr. Rob Zettle, Sarah Staats, Suzanne Gird
Front row: Sarah Heiman, Charles Hayes, Angela Cathey