Immune tolerance the resulting effect is similar. Immune tolerance is important for normal physiology. Central tolerance is the main way the immune system learns to discriminate self from non-self. Peripheral tolerance is key to preventing over-reactivity of the immune system to various environmental entities (allergens, gut microbes, etc.). Deficits in central or peripheral tolerance also cause autoimmune disease, resulting in syndromes such as systemic lupus erythematosus, rheumatoid arthritis, type 1 diabetes, autoimmune polyendocrine syndrome type 1 (APS-1), and immunodysregulation polyendocrinopathy enteropathy X-linked syndrome (IPEX), and potentially contribute to asthma, allergy, and inflammatory bowel disease. And immune tolerance in pregnancy is what allows
Behavioral immune system and behavioral reactions (e.g., arousal of disgust, automatic activation of cognitions that connote the threat of disease, behavioral avoidance). The existence of a behavioral immune system has been documented across many animal species, including humans. It is theorized that the mechanisms that comprise the behavioral immune system evolved as a crude first line of defense against disease-causing pathogens. Within the psychological sciences, there is extensive research linking the behavioral immune system to a variety of prejudices—including prejudices against people who aren't actually diseased but are simply characterized by some sort of visual characteristics that deviate from those of a subjectively