Researchers report the first physiologic evidence of the role of laughter during psychotherapy

Laughter may be the best medicine, but the role laughter plays in psychotherapy has been disputed since the days of Freud.

Some early therapists believed that laughter could have a harmful effect, while more recent thinking has held that, if used non-judgmentally, laughter can help support the therapeutic partnership. But none of those theories have been based on objective data.

In the October issue of The Journal of Nervous and Mental Diseases, researchers from Massachusetts General Hospital (MGH) report the first physiologic evidence of the role of laughter during psychotherapy. The researchers found that patients use laughter to communicate emotional intensity to psychotherapists, much like an exclamation point at the end of a sentence. In addition, patients' and therapists' laughing together magnifies that intensity and may contribute to feelings of rapport between them.

"Current research on laughter in general shows it is more about communicating emotion than about humor," says Carl Marci, MD, the director of Social Neuroscience in the MGH Department of Psychiatry, the paper's lead author. "Many therapists have been caught up in the old notion that laughter only signifies humor, even ridicule, and have questioned whether using laughter in therapy is appropriate. We wanted to take an objective look at the occurrence of laughter during therapy and measure its physiologic effect."

As part of a larger on-going study of psychophysiology and empathy, the researchers videotaped therapeutic sessions and took physiologic measurements of both members of ten unique patient-therapist pairs. The patients were being treated for common outpatient mood and anxiety disorders in previously established patient-therapist relationships. Participating therapists practiced psychodynamic therapy, an approach that uses the therapeutic relationship to help patients develop insight into their emotions.

Throughout the therapy sessions, physiologic responses were measured for both patient and therapist using skin conductance recordings. Skin conductance is a commonly used measure of the activity of the sympathetic nervous system, which controls physiologic arousal and increases such parameters as blood pressure and heart rate. Earlier studies have shown that laughter increases arousal and that elevated skin conductance is associated with increased empathy between therapists and patients. Following the sessions, the videotapes were reviewed by independent observers who identified each laugh episode according to who was speaking prior to the laughter and whether the other person laughed as well.

In the ten recorded sessions, the observers identified 145 episodes of laughter, some involving both patient and therapist. On average, patients laughed more than twice as often as therapists did and were most likely to be laughing in response to their own comments. Therapists also were more likely to laugh in response to what patients had said. The skin conductance measurements showed that laughter produced physiologic arousal in both patients and therapists, with arousal strongest when both laughed together.

"We were surprised to find how common laughter was in therapy," Marci says. "Taken together with the current understanding of laughter outside of psychotherapy, our findings suggest that the patient who is laughing is trying to say more than has been expressed verbally to the therapist. Laughter is an indication that the subject is emotionally charged."

The rare occurrence of laughter among therapists and the fact that they almost always laughed in response to patient comments reflects the focus of therapy on the patient's emotions, according to Marci. He also notes that therapists showed a physiologic reaction to patients' laughter even when not laughing themselves, indicating an empathic response to their patients. When therapists did laugh, patients' physiologic responses went even higher, supporting the well-known contagion of laughter and suggesting that, when therapists laugh with patients, the patients feel validation of the emotions they are expressing. "The clinical implications of the findings support the need for therapists to pay closer attention to when patients laugh during psychotherapy. Therapists should explore the meaning of what is said immediately preceding laughter," says Marci, an instructor in Psychiatry at Harvard Medical School.

The researchers' next step is a longer-term study, examining how the occurrence of laughter evolves as the therapeutic relationship develops with the ultimate goal of finding any significant relationship between laughter and improved mental health for patients. Marci's co-authors are Erin Moran of MGH and Scott Orr, PhD, of MGH and the Veteran's Affairs Medical Center in Manchester, N.H. The study was supported by grants from the National Institutes of Health and the MGH Endowment for the Advancement of Psychotherapy.