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The Cold Bottom Reflex – A Previously Unknown or a Forgotten Micturation Reflex?

Peeing or, more delicately, urination or, medically and even more delicately, micturation, is, contrary to popular opinion, a rather complex behaviour. In human infants and animals it seems spontaneous. In humans and some domestic animals it can be brought under conscious or voluntary control. In humans this is called, somewhat ambivalently, ‘potty training’. In domestic animals it is called, rather confusingly, ‘housebreaking’ in American English or, slightly more logically, ‘house-training’ in British English. In many other animals, who use urine as scent or territory markers, it must also, at least partly, be under voluntary control. However, even if brought under voluntary control, it still sometimes happens that in healthy individuals some external stimuli may provoke the urge to urinate as if by reflex.

One urban legend says that urination can be induced in a sleeping person by holding one of his hands in water. There is considerable disagreement about this putative phenomenon.[1]

Other much reported provoking stimuli of micturation are (1) the sound of running water, for example in taps, fountains, and waterfalls, (2) hand-washing in cold water, and (3) being in a loo / toilet / bathroom / washroom / restroom, as if by a conditioned reflex.[2]

He stared at a big bleary bald-headed sixty-year-old man in the mirror. He turned on the cold water at one of the bassins and cupped his hands and rubbed water over his face The water really made him want to urinate, and so he went over to the toilet, which was some streamlined, low-slung beige thing, and he urinated. Was this a bad sign, the urge he had always to urinate in the middle of the night?[3]

In this literary passage it is unclear – apparently also for the novelist – whether the urge to urinate is caused by the washing of hands in cold water, by the splashing of cold water on the face, or by the sound of running water, or – prosaically – because of an age-effect on the bladder and its sphincters.

There are probably at least two more local stimuli of the micturation reflex. The first stimulus is invasive and is used as an experimental and diagnostic tool. In the ice-water test (IWT) cooled water is

injected through a catheter into the bladder.[4] The second stimulus is non-invasive and is used as a means to induce urination in women who have recently given birth and are experienceing difficulty or pain urinating. The author of a popular self-help book advises:

You can encourage the urine to start flowing again by […] placing hot or cold packs on your perineum (whichever triggers your urge to urinate).[5]

Interestingly, the author writes also:

If it’s good old-fashioned fear that’s holding you back, you might want to try drinking plenty of liquids to dilute the acidity of your urine, straddling the toilet saddle-style when you urinate, urinating while you pour water across your perineum (you can use either a peri-bottle or a bowl), or — if you really get desperate — urinating when you’re standing in the shower.[6]

This advice comes closest to the idea conveyed in a passage that originally triggered my curiosity. In 1964 the Dutch writer and painter Jan Cremer published his first novel which became a best-seller and a cause célèbre. In this supposedly autobiographical picaresque Cremer described his childhood friendship with a young mother around 1950:

If I happened to be in the street in the afternoon when Betty came home with the baby carriage, she’d say to me, “Come in and watch Bartje piss,” and I’d go in with her. She would change his diaper and sprinkle a little cold water on his ass, and he’d react immediately by pissing until his little bladder was empty.[7]

Apparently ‘Betty’ used this trick to ensure that her baby boy ‘Bartje’ would have an empty bladder when getting a dry and fresh diaper. This was before the days of disposable diapers and Bartje’s diapers were most likely made of cotton. It was in his mother’s interest that Bartje would have a dry diaper as long as possible. Ensuring that Bartje’s bladder was empty when his diaper was getting changed was one way to do this.

Maybe it is the same reflex that is responsible for the often observed peeing while undoing a used and wet diaper. In such cases, especially boys can cause hilarity when they spray with urine the unexpecting adult who undresses the diaper.

Maybe the putative reflex was painted by Rembrandt. Ganymede’s bottom region must have become relatively cold when being airlifted. An alternative explanation for the airborne micturation could be that Ganymede urinated because of ‘real stress’ incontinence: the distress or hightened negative stress that was caused by the situation in which he suddenly and unwillingly had found himself.

The reflex may thus be provoked by sudden cooling of the natal region and it might therefore be called the cold bottom reflex.

To my surprise, I found no references in the scientific literature of this putative reflex. Also in recent handbooks of practical baby care I did not come across this parental trick. Therefore the following questions must be addressed: (1) is this a genuine phenomenon and reflex or was it an instance of poetic licence by Jan Cremer? and (2) if this is a genuine reflex, was it and its practical applicability forgotten? or (3) was it a private observation and lucky discovery by ‘Betty’ that was recorded accidentally by Jan Cremer?

Wolter Seuntjens

Dutch Academy of ’Pataphysics, Amsterdam


Notes and References:


[2] Radley, S., J. Derek and C. Chapple, ‘Ambulatory Urodynamic Monitoring’, in The Urinary Sphincter (eds. J. Corcos and E. Schick), New York: Marcel Dekker, Inc., 2001, pp. 335-55 (p. 352).

[3] Tom Wolfe, A Man in Full. New York: Macmillan, 2010 [1998], p. 138.

[4] Al-Hayek, S. and P. Abrams, The 50-year history of the ice water test in urology. Journal of Urology 183, 2010:1686–92.

[5] Ann Douglas, The Mother of All Pregnancy Books: An All-Canadian Guide to Conception, Birth and Everything in Between. Hoboken (NJ): John Wiley and Sons, 2009.

[6] Ibid. The‘peri-bottle’ is a squeeze bottle named after and used specifically to cleanse the perineum.

[7] Jan Cremer, I, Jan Cremer. (English Version by R. E. Wyngaard and Alexander Trocchi), London: Calder & Boyars, 1965 [1964], p. 48.