By Mary O’Brien, M.D.
“Stop that crying, young lady, or I’ll give you something to cry about!” Most of us heard something similar growing up. Certainly, there is a time and a place for tears. However, what most of our parents, teachers, or coaches did not understand was how complex and profound crying can be. The neurophysiology of crying is far more intricate than most of us realize.
Crying, to oversimplify greatly, involves the autonomic nervous system, the frontal and prefrontal cortices, the brainstem, hypothalamus, basal ganglia, amygdalae, vagus and trigeminal nerves, heart, lungs, facial muscles, larynx, pharynx, eyes, nose, and throat — as well as a host of neurotransmitters. Anthropologists believe that, in humans, crying developed long before speech. As tears begin to flow, we become choked up and speechless. This may explain why crying reveals emotional states that are nearly impossible to express in words.
Clearly, tears can be shed in response to pain and physical distress, as well as to fear and anger. All mammals experience fear largely as the result of having a limbic system. Given certain circumstances, most mammals can express anger. Grief, mourning, and bereavement can move people to tears at any age and in every culture. Some animals such as dogs, elephants, and primates can manifest behaviors suggestive of loss or grief, but these animals’ ability to shed tears in response to grief has not been scientifically verified. Grief and mourning have a cognitive component.
Human beings are social creatures. Barring neurologic anomalies, humans can cry from the moment of birth onward. The tears, vocalizations, and facial expressions of crying signal a universal plea for help and empathy. Tears elicit a change in the mindset and behavior of the person who cries and in those who witness the crying. It’s not rare for someone to “feel better” after a “good cry.”
The ability of humans to feel empathy and compassion for others has had a profound effect on culture and civilization. Without these emotions, there would be no such thing as hospitals, orphanages, disaster relief, or volunteers of any sort. The capacity for compassion is not present to the same extent in everyone. Some individuals have no empathy or compassion at all. Others are veritable saints. The next time you feel moved to tears, don’t fight it. It may just mean your humanity is still intact.
Trimble, Michael, Why Humans Like to Cry, Tragedy, Evolution, and the Brian. Oxford, UK, University Press, 2012.