Today’s Friday Weird Science comes to you courtesy of the perspicacious Ivan Oransky, who was kind enough to send me this paper. And this paper is great. It’s proof that anything is worth measuring if you do it in an fMRI.
Have you ever wondered what happens to your brain when you pee? What areas might be active which allow that glorious golden shower? What is responsible for that feeling of relaxation and release? That feeling of relief when you REALLY have to go?
….do you have to pee RIGHT NOW? I bet you will by the end of this.
Krhut et al. “A Preliminary Report on the Use of Functional Magnetic Resonance Imaging with Simultaneous Urodynamics to Record Brain Activity During Micturition" Voiding Dysfunction, 2012.
The authors of this paper care about peeing. Really, aside from the morbid curiosity, there is good medical reason to know what happens in your brain when you pee. There are all sorts of urinary dysfunctions, and many of them are not just problems with the bladder, but could arise from issues in the brain. So know what parts of the brain are important in your whizzing streams could help us find out what goes wrong when people, say, lose urinary control after stroke.
But still…this is people peeing in an MRI. On to absorbent puppy pads. That’s some good humor right there.
The authors gathered 12 women willing to pee in an fMRI. fMRI is functional magnetic resonance imaging, a technique that allows you to see, with really good anatomical localization, what parts of the brain are receiving more oxygenated blood during a given task.
They put the women in an MRI machine and made them pee. You’d think they’d be so kind as to maybe make them drink a few liters worth of margaritas or at least Tang, or maybe even WATER. But no. No, they wanted pee they could CONTROL. So that means a nice big urinary catheter used to fill the bladder artificially.
I can see a lot of volunteers hearing about that one and suddenly deciding to be VERY busy that day…but don’t worry, it’ll only hurt for a minute!
They filled the urinary bladder several times over the course of the MRI, and had the women pee (I hope they used a LOT of absorbent pads, and switched them out. Otherwise this could get pretty uncomfortable after a while…). And then they looked at the brain.
What you can see here is the fMRI signal, correlated with the moment in time in which the bladder was filled and the women let it all out. And they got some nice signals when the bladder awas full and as the women peed in the parahippocampal gyrus, temporal lobe, and parietal lobe, as well as the thalamus and the pontine region. It’s possible that these regions are involved in things like the sensation of bladder fullness (“I gotta go!”) and the urge to urinate.
But then they found something interesting. Some of the women just COULDN’T pee. Maybe it was the lying down? Maybe it was the peeing on command? Whatever it was, the women just couldn’t go. And you could see the difference in their MRI signal (though the numbers were too low for analysis, so who knows if it’s really real). These women showed increases in blood flow to the inferior frontal lobe and posterior cingulated, but no activation in the thalamus and pontine regions. Maybe this lack of activity is important, but sadly there’s really not enough people who could pee vs. who couldn’t to make a distinction.
And my friends, this is why science needs YOU! Can you pee lying down? Have you ever tried?! If you can, we need YOU to come and get a catheter and pee in an MRI. And if you can’t? Well we need you, too! Would YOU pee in an MRI for SCIENCE?
Krhut J, Tintera J, Holý P, Zachoval R, & Zvara P (2012). A Preliminary Report on the Use of Functional Magnetic Resonance Imaging with Simultaneous Urodynamics to Record Brain Activity During Micturition. The Journal of urology PMID: 22698619