Psychoneuroimmunology: new avenues of research for the twenty-first century.

Psychoneuroimmunology (PNI) investigates the relations between the psychophysiological and immunophysiological dimensions of living beings. PNI brings together researchers in a number of scientific and medical disciplines, including psychology, the neurosciences, immunology, physiology, pharmacology, psychiatry, behavioral medicine, infectious diseases, and rheumatology. All are scientists with profound interest in interactions between the nervous and immune systems, and the relation between behavior and health. Despite the variety in domains and approaches to research, the outcome common to all research endeavors is the discovery of new information, of uncovered facts, of novel evidence, which contributes to the continuing generation of knowledge. In this paper we discuss psychoneuroimmune aspects of some conditions that are not routinely immediately associated with immunity, such as the condition of being the caregiver of somebody suffering from dementia; the effect on the brain-body modulations of aluminum, a metal that is not a component of the human body; and insomnia, a fairly common but disturbing disease, that even today lacks an effectual treatment.