Crying

Crying is the shedding of tears in response to an emotional state. The act of crying has been defined as "a complex secretomotor phenomenon characterized by the shedding of tears from the lacrimal apparatus, without any irritation of the ocular structures". A related medical term is lacrimation, which also refers to non-emotional shedding of tears. Various forms of crying are known as weeping, wailing, whimpering, and bawling.

For crying to be described as sobbing, it usually has to be accompanied by a set of other symptoms, such as slow but erratic inhalation, occasional instances of breath holding and muscular tremor.

A neuronal connection between the lacrimal gland (tear duct) and the areas of the human brain involved with emotion has been established. There is debate among scientists over whether or not humans are the only animals that produce tears in response to emotional states.Charles Darwin wrote in The Expression of the Emotions in Man and Animals that the keepers of Indian elephants in the London Zoo told him that their charges shed tears in sorrow.

Tears produced during emotional crying have a chemical composition which differs from other types of tears. They contain significantly greater quantities of the hormones prolactin, adrenocorticotropic hormone, and Leu-enkephalin, and the elements potassium and manganese.

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