Tears are drops of liquid produced by the lacrimal, accessory lacrimal, and Meibomian glands, that contain proteins, enzymes, lipids, metabolites, electrolytes and traces of drugs.Well, that’s one way of putting it.
We also know that the chemical composition of tears differs depending on what caused them to spill: crying versus chopping an onion, for example. Is it possible that tears shed during crying contain chemical signals that have an effect on other people?
A group of researchers in Israel recently came up with multiple lines of evidence suggesting that women’s tears have a fairly specific effect on men; and it isn’t a pretty one.
To do research on human tears, you first need to collect some. Shani Gelstein and her colleagues did this the obvious way—by showing chick flicks to women and collecting the weepy output in small tubes. (This technique clearly wouldn’t work with guys; you’d have to show them the grenade scene from The Dirty Dozen.) Gelstein’s team created control “tears” by dribbling saline solution down the cheeks of each sob sister, thus giving the fake tears whatever odors might come from contact with the skin.
Despite the presumed difference in chemical makeup between cried tears and pseudo-tears, a couple of dozen young men who sniffed them could not tell them apart. Nor did another group of men find any difference in the intensity, familiarity, or pleasantness of the odor of cried tears versus saline. But then each men rated emotionally ambiguous pictures of women’s faces for sadness and sexual attraction, while wearing a tear- or saline-soaked blotter on his upper lip.
The upshot? When a guy was smelling emotional tears, the women’s faces didn’t look sadder—they looked less sexually attractive.
You’re gonna cry, cry, cry, cryGelstein et al. reasoned that a tears-causing-sadness link might emerge in a sad context. So they had another group of guys watch a sad movie while wired for physiological responses (heart rate, skin temperature, etc.) and while providing saliva samples to be assayed for testosterone. In one session they watched a film after sniffing cried tears; in another they watched after sniffing fake saline tears.
By itself, watching the sad film put the guys into a significantly more negative mood; it was an effective downer. Real tears had no effect on self-rated mood, but did reduce self-reported sexual arousal and the amount of testosterone found in the men’s saliva.
Finally, Gelstein’s team put guys in an MRI magnate and showed them dirty movies, in order to localize the arousal-related areas of each fellow’s brain. The men then watched sad, happy and neutral movies after sniffing tears or saline. Activity in the sexual arousal brain areas was significantly lower for the sad movie watched after smelling real tears.
Subjective ratings of attributed sexual appeal, together with objective measures of psychophysiological arousal, testosterone expression, and brain activity, jointly suggest that women’s emotional tears contain a chemosignal that reduces sexual arousal in men.Hmm . . . that rings a bell.
Everytime we say good nightHuman tears contain a chemosignal, by S. Gelstein, Y. Yeshurun, L. Rozenkrantz, S. Shushan, I. Frumin, Y. Roth, and N. Sobel, was published January 14, 2011 in Science. 331:226-230.
As I go to hold her tight
Never get to kiss her ‘cause she cries
Oh baby don’t (baby don’t cry)
Oh baby don’t (baby don’t cry)