Science makes you smile!

I'm in the lab today messing with a piece of equipment I haven't used in years and trying to remember how it works. It's called "neck suction" and as you can see from the subject's reaction to the left there, it's incredibly awesome. A laugh riot, even. The equipment consists of a neck collar attached to a pressure bellows, that in conjunction can increase or decrease the air pressure around your neck... or more specifically your carotids... causing the vessels to either contract or distend respectively. This fools the carotid barorecepters into thinking blood pressure has increased or decreased... so your heart rate will change in response... but only for a few beats, since they're not easy to trick. As you can see from the uhm... somewhat dated look of the picture, this is fairly old skool technology, but it's still handy because it's noninvasive and as such you don't need to use any drugs to probe the physiology. It's also kind of a PITA to work with... which how this post which nobody cares about is really a long winded explanation as to why posting will remain light to today.