Question: What was the most dangerous experiment you have done?

David McGonigle answered on 26 Mar 2021:

Hiya rays! Some have been dangerous in different ways – but in general, because of the way that science works in most societies, they’ve only been dangerous to the idiot trying them (that’s me, by the way!). Often in science we do a ‘pilot’ experiment to check out if equipment works, and make sure everything is wired up right. So during my PhD, when I was better at doing electronics, I made a device to ‘buzz’ under peoples’ fingers during an MRI scan. This would allow me to record where in the brain the signal from their fingers was going. For once, as I was running the scan, I asked a friend to go in the mri machine and be my ‘pilot participant’ – I could check the images from his brain if all was ok. So we started the scan, and all was going fine. I was watching the images being collected and I became aware of a weird blue light coming from somewhere. I looked up, through the screen (there is a glass screen between the control room of the MRI and the MRI itself) and I was horrified to see the there was a massive arc of electricity going from the MRI casing to my buzzer box. It was like a laser gun from star wars, crackling and buzzing. But of course, my friend couldn’t see this – he was too far in the MRI. I immediately stopped the scan, turned off the buzzer, isolated the wires, and hurriedly got my friend out. ‘That was a short experiment’, he said, and walked off. I spent the next month insulating and fixing my buzzer – and it worked perfectly from there out….!