By Nikhil Ramburn and Sat Bir Singh Khalsa, Ph.D.
Schizophrenia is a severe mental disorder that impacts a person’s cognitive and social abilities. The symptoms may include delusions, hallucinations, lack of motivation, reduction in spontaneous speech, and social withdrawal. The clinical symptoms of schizophrenia often represent typical examples of self-disturbance as patients struggle to recognize themselves as the source of their own thought and actions and are confused about self/non self-boundaries. Individuals suffering from schizophrenia may experience multiple acute episodes throughout their lifetimes and medical morbidity and mortality rates remain elevated in these patients. Naturally, this psychopathological condition greatly decreases an individual’s quality of life and social and occupational functioning, which in turn creates a considerable socioeconomic burden.
While there is no specific known cause of schizophrenia, most psychiatrists agree that it is multi-factorial. Individuals may likely have a genetic predisposition toward the condition, which may be activated by environmental stressors such as perinatal viruses, obstetric complications, and childhood trauma. There may be a neurodevelopmental aspect to schizophrenia, where excessive amounts of dopamine in brain regions such as the hippocampus are believed to play a role in the development of the illness. In addition, patients with schizophrenia frequently have a high baseline level of physiological arousal where the body is chronically agitated and alert. This is often compounded by a suppressed parasympathetic nervous system, which regulates the body’s capacity to calm down. This hyper-responsivity to stress may in turn lead to chronic activation of the body’s stress-response system including the autonomic system (sympathetic and parasympathetic) and the hypothalamic-pituitary-adrenal (HPA) axis and contribute to prolonged mental and physical distress. Unfortunately, stress is both a trigger and by-product of schizophrenic episodes. Other lifestyle risk factors include the lack of physical activity and a fast and shallow breathing pattern, which can exacerbate the stress reactivity.
Conventional treatment for schizophrenia primarily includes pharmacotherapy and psychotherapy. While antipsychotic medication has greatly reduced morbidity and mortality, it comes at the cost of severe side effects, as most patients need long-term treatment. Therefore, complementary and integrative medicine (CIM) are extensively sought after with 63% of psychiatric patients using CIM therapies including yoga especially in depression and anxiety disorders. Indeed, several of the disease factors can be addressed by a therapeutic yoga intervention. Influential models of schizophrenia suggest that a disturbed sense of self (the inability to distinguish self from non-self) is a core component of the illness. Studies in healthy individuals indicate yoga practices may improve self-reflection through highly focused attention, sustained posture, breath regulation, and meditation techniques. Indeed, to distinguish the conscious self who is the agent (purusha) from that which can be objectified and is the content of experience (prakrti) determines the integration of the self in yogic philosophy.
In addition, biomedical models provide further rationale for therapeutic yoga interventions. Yoga could enhance quality-of-life in schizophrenia patients by improving social cognition and empathy through the reinforcement of the premotor and parietal mirror neuron system. This neuron system is activated both by acting or observing the same action by another person. Yoga classes facilitate this process by teaching coordinated physical postures through imitation. Oxytocin, a hormone involved in social bonding is also produced in the experience of enhanced social connectivity of yoga classes, leading to better social cognition and improved social outcomes. Exercise has likewise proven beneficial for patients with schizophrenia, yielding improvements in clinical symptoms, quality of life, and global functioning. In addition to the benefits of conventional exercise, yoga may also have a positive effect on cognition, which particularly highlights the therapeutic potential of yoga in conditions like schizophrenia. This is particularly relevant for traditional styles of yoga that incorporate meditation, which may help in strengthening the lateral and medial pre-frontal brain networks. Finally, the stress reduction benefits of yoga and meditation in normalizing the function of the HPA axis and increasing parasympathetic activation are well-known.
While prior systematic reviews have suggested the efficacy of yoga in relieving schizophrenia symptoms, the first meta-analysis was published by Cramer et al. in 2013 and included five randomized controlled trials RCTs from India, China, the USA, and Belgium with a total of 337 patients. Yoga interventions in these studies included postures/exercises, pranayama, and meditation/mindfulness and were compared either to usual care, exercise, or both. Intervention lengths and intensities varied between a single 30-minute session to 25 45-minute sessions over a period of 1 month followed by 3 months of home-based yoga. This systematic review found moderate evidence for short-term effects of yoga on quality of life scores and effects were present only in studies with high risk of bias, with no evidence for short-term effects. Despite study limitations such as possible bias and small sample size initial results are encouraging and suggest that yoga may be useful in treating clinical symptoms while improving socio-occupational functioning in schizophrenia patients.
The first study to examine the effect of yoga therapy on oxytocin levels in schizophrenia was also published in 2013. This RCT was conducted by Jayaram et al. in the laboratory of Dr. B.N. Gangadhar at the Integrated Centre for Yoga within the prestigious National Institute of Mental Health and Neurosciences in Bengaluru, India. The study included a total of 43 patients that were maintained on antipsychotic medication and randomly assigned to receive either the yoga intervention or to continue on medication alone. The yoga therapy group showed a significant improvement in socio-occupational functioning, which is consistent with previous findings, but also showed an increase in plasma oxytocin levels. Apart from the increased social interaction of yoga classes, yoga may modulate oxytocin synthesis by increasing the activity of the vagal nerve, highlighting its potential efficacy as an adjunct treatment for schizophrenia.
In summary, studies to date have demonstrated the moderate short-term efficacy of yoga to improve clinical symptoms of schizophrenia while providing socio-cognitive benefits. This is a cost-effective and empowering practice that allows a patient to recognize that behavioral skills such as deep breathing and meditation can alleviate emotional and psychological distress. However, given the fact that this is a new field of clinical investigation, the results must be considered as preliminary in nature, and further evidence is required before recommending yoga as a routine intervention for schizophrenia patients. Current ongoing research at a large academic center in New Delhi, India is using a 3-armed RCT to examine the effectiveness of yoga supplementation as compared to physical exercise and conventional treatment to evaluate cognitive state, overall function, and symptom severity. It is likely that new publications will appear regularly from recently completed clinical trials in this growing field of research.