Psychoneuroimmunology, or PNI, is the study of the connection between the brain and the immune system. Studies began in the 1970's connecting psychological experiences and immune function. To this day there is some debate on the validity and of the use of this science to promote alternative medicine. .
Robert Ader and Candice Pert, among other pioneers, began research on psychoneuroimmunology in the 1970's. A new type of medicine was created in 1977 at a conference at Yale University called Behavioral Medicine, which opened the doors to this new emerging field of scientific research. Ader is known as the father of psychoneuroimmuology. Pert is the founder of emotion-modulating peptides.
Psychoneuroimmunology, which is the study of the connection between the brain and the immune system, can be explained biologically. Only two percent of neuronal communication is electrical and the other ninety eight percent is chemical. The chemicals used in neuronal communication are two different classes of peptides. Peptides are small chains of amino acids. There is a special class of peptides called cytokinins that work on the cell surface receptors of immune and nerve cells. The immune system and the nervous system both rely on these chemical messengers. This chemical is released into the immune system through the bloodstream and into the nervous system via the cerebro-spinal fluid. The immune and nerve cell types create the chemical separately and yet they are identical. A person's mental-emotional state determines their health by determining which of these peptides and cytokinins are produced. .
There are some debates on how reliable this science is. Some researchers say that there is no biological link between the two systems. Then others say they have found it. Another affair of PNI is that the father of it, Ader is concerned that some of his colleagues use data from psychoneuroimmuology to legitimize alternative therapies of which he does not approve.