The human body and its working has always been a subject of great interest to many. This science attempts to analyze the effect of mental and emotional factors in healing processes. Research shows that the defense mechanism of the human body and its resistance to various disorders is largely influenced by psychological processes. Evolution of PNI The birth of PNI as a separate science took place in the early 19th century. Walter Cannon, a professor at Harvard University, first observed and studied the link between physical and mental processes in organisms. Further research showed how emotions such as anger, fear, and happiness affected the neuro systems, and hence, the body. Hans Selye subjected animals to adverse physical and mental conditions, and observed their responses. The mental state of animals was found to have a significant impact on their recovery. It was Robert Adler and Nicolas Cohen who did pioneering research and coined the term 'Psychoneuroimmunology': Psycho for mind, Neuro for neuroendocrine system, and immunology for immune system. Further, different people were examined with respect to their resistance to diseases and mental conditions. The results were a revelation! The subjects with a mentally tough character or relatively peaceful disposition and composed thought process were better at resisting illness as compared to others. In the year 1964, George Solomon, an American professor, published a landmark paper titled, 'Emotions, Immunity and Disease'. These efforts conclusively proved the deep relationship of human psychology and well-being. PNI has expanded and reached deep into the human physiology. The study now involves the scrutiny of exact mechanisms in the brain, which lead to such immunity and resistance to harm. Deliberate changes in the psychosocial activities have influenced the health system of individuals. Stress and disease are deeply inter-connected. Events such as the death of a loved one or facing a natural calamity severely affect the immune system. Researchers study the changes in hormonal balance, emotional and behavioral adaptations to stress. These changes are essential to preserve the working harmony of mind and body, if the duration is limited. After a certain point, stress affects the balance between mental and physical states of the body. Everyday Evidences Allergies in human systems have their origin in the psycho-neuro relationship. Depression is characterized by reduction in immune mechanism due to psychological changes. It is astonishing to learn that introvert personalities are more susceptible to viral infections like cold or influenza. Cardiovascular diseases, skin disorders, and obesity can be substantially influenced by psychoneuroimmunal behavior. This field is a complex integration of already complex branches of science. However, it also presents a complete understanding of the biological processes. This has had a significant impact on the human health research. Religious Influences People who are religious and forgiving have a more positive set of emotions. Such people were found to have a strong and healthy immune system. Negative emotions cause deregulation in the resistance power. Research shows that cytokines, a type of protein, is secreted in response to any injury. Depending on the type of emotion there are pro-inflammatory and anti-inflammatory cytokines. Such secretions attract immune cells to the damaged area, and stimulate them. They help in the recovery process if positive emotions activate them. PNI Research: Boon for Humanity Dr. Ian Weinberg, who has conducted pioneering research in the field of PNI, emphasizes this connection of the mind and body. He states that individuals who are purposeful, optimistic, and inspired in their life, are more resistant to illness than those with a negative attitude. The mind plays a vital role in the physical well-being of an individual. Therefore, it is essential that one develops a spiritual and positive attitude towards life. In fact, many of the spiritual and religious discourses already credit a balanced and healthy life to positive energy. Modern living is hampered by the stress-prone human lifestyle. Constant deviation from spirituality has a profound impact on human fitness. This has been duly credited to psychoneuroimmunal factors affecting us. Genetic research shows how miracle healing and defense mechanisms of the body are linked to inner life of man. PNI study also shows how meditation, yoga, tai chi, and other such practices heal the human system. These techniques are the support systems of the natural healing process of our body. It is important to realize that the human body is not just an assembly of physical parts―it is a combination of the inseparable entities―the mind, body, and spirit. Today, psychoneuroimmunology goes a step further and explains how the immune system can be strengthened by psychological techniques. Let us hope that the wonderful science of PNI takes us one step closer to God.