Mirror neurons are hot these days, and here’s a mirror neuron story with a twist. You probably know that you don’t need to do something yourself to activate the relevant motor pathways in your brain; just watching another person perform a physical motion is enough to get your neurons going, mirroring the activity you see. How does the brain respond, though, in people who are physically incapable of making the moves they’re seeing others make? It turns out that their brains react in ways that capture the intent of the motion, even if they can’t mimic the actual motion itself. A recent study looked at 16 normal subjects and 2 aplasic subjects (born with no arms or hands). The subjects’ brains were scanned with fMRI while they watched a video of hands doing various handy things. When the hands in the video reached for a cup, the brains of the normal subjects showed activity in the parts of their brains involved in holding a cup. However, the brains of the aplasic subjects showed activity in the motor pathways responsible for moving their feet, indicating that they were mirroring the fact of cup-moving (which they can do with their feet) rather than the specific method of cup-moving. This article from Science Now has more information.