By JanSev Singh and Sat Bir Singh Khalsa, Ph.D
Research on the therapeutic value of yoga has been growing rapidly, including research studies that are becoming more rigorous in research design, and studies that are evaluating diseases never before evaluated. Had you asked just a decade ago whether yoga might have been useful for more serious psychiatric conditions such as autism, psychosis or schizophrenia, the answer would likely have been an outright negative or at least an expression of strong skepticism. However the efficacy of yoga as therapy seems to know no bounds, and there is now credible evidence emerging in favor of yoga for treating such disorders, especially for the psychotic disorder schizophrenia.
What are psychotic disorders?
A psychotic disorder refers to an abnormal or deranged function of an individual’s mental state with delusional and paranoid tendencies as well as depression, social dysfunction, endocrine irregularities and lack of motivation. Schizophrenia and psychosis stand out among psychotic disorders listed in the DSM-V (the widely accepted clinical reference text for psychiatric diagnoses) for their highly debilitating symptoms and the ongoing struggle to effectively provide treatment. The prevalence of schizophrenia is roughly 5 people affected in 1,000 and more than 60% of the patients diagnosed with schizophrenia have recurring symptoms for life. A lack of understanding of schizophrenia makes the disorder a burden to diagnose, let alone treat. Risk factors include an individual’s genetic predisposition, exposure to chemicals, pharmaceuticals and recreational drugs and low socioeconomic status.
Because the underlying causal factors for schizophrenia are not yet fully known, the best course of action for clinicians is to aim at symptom control. Drug therapy treatments have made significant advances, especially with so-called “positive” symptoms such as delusions and hallucinations, while the “negative” symptoms (amotivation and depression) as well as cognitive symptoms tend to linger. Also, pharmacotherapy for schizophrenia has been known to cause other complications both clinical and psychological, leading to a desire for possible effective behavioral treatments that would eliminate both side effects and compliance issues with medications. Given that yoga therapy has been shown to improve emotion regulation, cognition, endocrine function and metabolism as well as menstrual dysfunction, it is not surprising that it has been considered for psychotic disorders. As it turns out, yoga appears to have potential benefit for schizophrenia. Over a dozen research trials evaluating yoga as a primary or adjunct treatment for this disorder have been published over the past six years, many of which were conducted by the research team of Dr. B.N. Gangadhar at the Advanced Center for Yoga, Mental Health and Neurosciences within the prestigious National Institute of Mental Health and Neurosciences in Bengaluru, India, which is India’s premier psychiatric treatment and research institution. In fact, the quantity of this research has led to publication of at least three review papers summarizing this evidence, although given the small number of trials, most of which are preliminary in nature, only modest conclusions of efficacy are possible at this point in time.
Yoga Research for Schizophrenic Patients
In a study by Gangadhar’s group published in 2012, schizophrenic patients were tested using a Positive and Negative Symptom Scale at the start of a four-month trial. During the four months one group practiced 45 minutes of yoga nearly every day while another group did not. The group that practiced yoga showed improvements, based on a negative symptom scale report, of 35 percent of the patients the while less than 10 percent of the patients who did not practice yoga showed improvement. Other studies that focused on yoga as an add-on therapy showed improvements in both negative and positive symptom scales and even quality of life scales. While the biological mechanisms of how yoga works are not entirely known, researchers have identified some possible explanations through experimental findings.
Schizophrenic patients tend to display social cognitive deficits. It is understood that one particular hormone, oxytocin, modulates social cognition by enhancing the processing of positive social emotional cues. Individuals with low levels of oxytocin demonstrate impaired social functioning, as seen in individuals diagnosed with autism. One study which focused on oxytocin levels and social cognition indicated that yoga improved oxytocin levels in schizophrenic patients who were also undergoing pharmacological therapy. One explanation of how yoga affects oxytocin levels is through stimulation of the vagus nerve, which in animals has been correlated with increased oxytocin levels. Although the impact of yoga treatment has been reported in “negative” symptom scales, there are also studies that report improving trends in positive symptom scales as well.
Supported by just a few studies, yoga may also be proving a useful treatment for patients suffering from psychosis as an add-on or adjunctive treatment in patients concurrently treated with antipsychotics. Clinically, yoga seems to be most beneficial in promoting quality of life and alleviating negative symptoms such as social dysfunction and depression. In one study, psychotic patients in a yoga practice group displayed comparable improvements in negative symptom measures to those that exercised, but the yoga group’s depression ratings improved more sharply than those in the exercise group. Future research studies might aim at employing longer term practices in comparing yoga with exercise in order to reveal more differences between these two forms of add-on therapy, as other studies have already done in non-psychosis research.
Yoga offers an approach to healthcare that many allopathic researchers and practitioners have yet to fully understand, exerting its therapeutic benefit at the connection and interface between the mind and body. Fortunately there are inspired pioneer clinicians and biomedical researchers dedicated to the advancement of yoga therapy as an accepted clinical treatment. However, like research on other behavioral and psychological interventions, research on yoga comes with significant scientific and technical challenges including reliance on “subjective” measures and the possible influence of multiple confounding variables in the intervention. For example, a strength of the study in which oxytocin was reported to be elevated from yoga practice is the use of an “objective” biochemical measure. However, another possible mechanism by which patients could have improved in this study is the social exposure that came with attending a yoga class. Addressing this issue requires refinements/improvements in the experimental design to control for this variable. Once the volume of clinical research evidence becomes convincing, and the underlying psychophysiological mechanisms are more clearly understood, yoga treatment may ultimately become a routine prescription for various conditions by healthcare providers, and, at least in some cases, not just as an adjunctive treatment.