Systole heart beats—is cued by messages from the brain, reflecting the brain's responses to conditions of the body, such as pain, emotional stress, level of activity, and to ambient conditions including external temperature, time of day, etc. Electrical systole opens voltage-gated sodium, potassium and calcium channels in cells of myocardium tissue. Subsequently, a rise in intracellular calcium triggers the interaction of actin and myosin in the presence of ATP which generates mechanical force in the cells in the form of muscular contraction, or mechanical systole. The contractions generate intra-ventricular pressure, which is increased until it exceeds the external, residual pressures in
History of beliefs about the human body as Traditional chinese medicine, or western, which follows the Greek traditions of science and is more closely related to modern science despite original anatomists and ideas of the body being just as unscientific as Chinese practices. In Western historical research, scholars began investigating the cultural history of the human body in detail in the 1980s. The movement is particularly associated with the historian of medicine Roy Porter, whose 1991 article 'History of the Body' was a seminal study. 1995 saw the foundation of the journal "Body and Society", by which time the field of the history of the body was