A break from normal service today, as I thought I’d post up a little video of me being silly on stage on the occasion of Science Showoff a few weeks ago. Science Showoff is a fantastic open-mic night for science communication, organised by the inimitable Steve Cross of UCL. People get up on stage in the back room of a pub in Clerkenwell, and do science-y things for the amusement (and occasionally even for the education) of the crowd.
For their May event, I thought I’d have a go at re-creating the world’s first brain-imaging experiment, live, on-stage, using nothing more than a table, a rolling-pin, and a kitchen scale. How was such a feat accomplished (I hear you gasp, dear reader, in tones hushed with reverential awe)? I shall explain.
What’s often called ‘the world’s first neuroimaging experiment’ was conducted by a gentleman by the name of Angelo Mosso in the late 19th Century; a professor of physiology at the University of Turin. He’s generally credited with the notion that blood flow in the brain is related to mental activity; he arrived at this conclusion by studying patients with open head wounds – the pulsations of their dura would increase in frequency when the patients became agitated or engaged in some demanding mental task.
He also (apparently) designed an experiment in order to see the effect of increased blood flow during mental activity in ‘normal’, uninjured people. This was the first time an external apparatus had been used to visualise the internal processes of the brain – hence ‘world’s first neuroimaging experiment’. I say ‘apparently’ because the only write-up we have about the experiment is from William James’ journal of 1890:
“The subject to be observed lay on a delicately balanced table which could tip downwards either at the head or the foot if the weight of either end were increased. The moment emotional or intellectual activity began in the subject, down went the balance at the head-end, in consequence of the redistribution of blood in his system…”
Now, most people who’ve written about this experiment since, have generally cast doubt on the idea that this could ever actually work. But, being on occasion an incautious type, and thinking that even if it didn’t work it could at least be amusing, I figured I’d just give it a try. I used a couple of modern-day modifications – I got a cheap digital scale off Amazon, which could distinguish increments of 0.1g, and used a webcam pointed at the scale’s readout to display it to the crowd via a projector. I rested the head-end of the balance-board on the scale, and figured that any increase in blood-flow to the brain should result in an increase in weight on the scale. The able and moderately-willing volunteer for the experiment was my good friend Thom Scott-Phillips of Edinburgh (and Durham) University and the video was shot by Rita Santos. Unfortunately it’s impossible to make out the scale readout on the video, but it definitely worked. Oh yes. Absolutely. *Ahem*. I’m also slightly embarrassed to admit that it contains quite a few of the naughty swears, but, y’know, it’s just that kind of event. If it’s alright for Ben Goldacre, then it’s alright for me, dammit.
Without further ado then – the video (watch it on YouTube for glorious 720p):