[Emotional tears].

Emotional tears, an exclusively human means of communication, are complex and rarely the subject of scientific research. The same nerves, receptors, and transmitters seem to be involved in their production as those used for basal and reflex tears. However, stimuli must be received in a cognitive/social context, detected by "induction centers" in the telencephalon, and forwarded to effector centers. Increased concentrations of protein, prolactin, manganese, potassium, and serotonin have been detected in emotional tears. Various theories try to explain the reason for and benefit of emotional tears. A number of factors, such as ethnic group, social status, profession, hormonal situation, gender, and individual threshold, influence whether an individual is a "crier" or a "noncrier." Manipulative tears are a strong weapon for unbalancing other people, and the expression "crocodile tears" is used for both manipulative tears and aberrant gustolacrimal tears. Pathological crying occurs during depression, but it also occurs in the context of central nervous system disease as prolonged crying fits without cause or emotion. Absent emotional tearing is observed in congenital, often syndromal, disorders.