When I am sad, I cry. How are emotions linked to tear ducts?

Question

When I am sad, I cry. How are emotions linked to tear ducts?

Answer 1

a part of the brain is activated and it sets something off in the mind that is stress related and then it releases hormones that have to come out and they come out as tears.

Answer 2

Dr. William Frey, a biochemist in Minnesota, has researched the chemical content of human tears. One of the substances found in tears was the stress hormone ACTH. Thus it is possible that shedding tears helps to reduce excessive amounts of ACTH and perhaps other substances that accumulate following a stressful event. Dr. Frey has suggested that the purpose of emotional crying may be to remove waste products from the body, similar to other excretory processes

Frey's conclusion is that "we may increase our susceptibility to a variety of physical and psychological problems when we suppress our tears." Crying not only removes toxins from the body but also reduces tension. Studies on adults in psychotherapy have found lower blood pressure, pulse rate, and body temperature in patients immediately following therapy sessions during which they cried and raged. Similar changes were not observed in a control group of people who merely exercised for an equivalent period of time.

Other studies have shown that therapy involving high levels of crying leads to significant psychological improvement. Those patients who did not express their feelings in this manner during therapy tended not to improve, while those patients who did frequently cry in therapy experienced changes for the better.

From a biological perspective three kinds of tears are distinguished (Lutz 1999); "Basal tears" are continuous and lubricate our eyes; "reflex or infant tears" occur when we chop onions or receive a blow to the eye; "emotional tears" are psychologically caused.  Frey, Desota-Johnson, Hoffman & McCall (1981) present experimental evidence of the difference between the biochemical composition of emotional tears compared to irritant tears.  The protein concentration of emotional tears was 24% greater than irritant tears.  The complex proteins in emotional tears were those involved in the human stress response.  Frey et al proposed that tears performed a sort of physical catharsis, expelling toxins from the body.

A type of physiological catharsis was proposed by Efran & Spangler (1979).  Following a period of sympathetic nervous system hyperactivity, crying is part of a parasympathetic rebound effect in which tears serve to discharge arousal.