Pupillary response Pupillary response Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve. A constriction response (miosis), is the narrowing of the pupil, which may be caused by scleral buckles or drugs such as opiates/opioids or anti hypertension medications. Constriction of the pupil occurs when the circular muscle, controlled by the parasympathetic nervous system (PSNS), contracts. A dilation response (mydriasis), is the widening of the pupil and may be caused by adrenaline, anticholinergic agents or drugs such as MDMA, cocaine, amphetamines and some hallucinogenics. Dilation of the pupil occurs when the
The purpose of a system is what it does The purpose of a system is what it does The purpose of a system is what it does (POSIWID) is a systems thinking heuristic coined by Stafford Beer. Stafford Beer coined the term POSIWID and used it many times in public addresses. In his address to the University of Valladolid, Spain, in October 2001, he said "According to the cybernetician, the purpose of a system is what it does. This is a basic dictum. It stands for bald fact, which makes a better starting point in seeking understanding than the familiar attributions of good intention, prejudices about expectations, moral judgment,