One of the scientific reasons why vaccination or immunization works can be attributed to the existence of biomemory cells (not to be confused with memory chips in computers). Wherever and whenever viral or bacterial infections happened the healthy normal immune system secretes a protein molecule called immunoglobulin (antibody) that binds to a particular antigen and marks it for subsequent destruction. The lymphocytes (white blood cells) both B cells and T cells were the first to detect the antigens (alien or foreign relative macromolecules that entered the body: viruses, bacteria, and many other chemical toxins). The B cells were developed and matured in the bone marrow while the T cells including the helper cells and cytotoxic cells develops to maturity in the small thymus gland found in the thoracic cavity which also encloses the lungs and the heart. T cells are responsible for cell-mediated immunity while B cells differentiate into antibody-secreting plasma cells as the effector cells of humoral immunity. Effector cells are muscle cells or gland cells that response to stimuli or signals from the brain or other nerve centers. The information gathered by the T helper cells triggers clonal expansion and antibody secretion by B cells. Small sets of cloned B cells become the memory cells formed during primary immune response which appears after a time lag of 10 to 17 days. Nevertheless, these memory cells stay in circulation inside the lymphoid organ until activated by exposure to the same antigens. Activated memory cells mount the second front defense as secondary immune responses which are more rapid (within hours), of greater strength, and of longer durations.

On the other hand, human memory occurs in two stages: short-term (STM) and long-term (LTM) memory. These are controlled by a network of different types of biomemory cells called neurons. Contrary to the local individualized B cells, global network of neurons learn by transferring sensory information temporarily in STM and by repeated rehearsals (“practice makes perfect”) these become permanently stored in LTM. Moreover, neurons learn and remember between facts and skills (e.g. the Rainman Syndrome, see http://www.guardian.co.uk/world/2009/dec/22/kim-peek-rain-man-dies ). Fact neurons are directly related to intelligence prions while skill neurons are directly related to motor activities such as walking, eating, riding bicycles, and dancing. Once a skill neuron is in place, it is very difficult to unplaced.