There’s a really cool paper by Giacomo Rizzolatti and Laila Craighero that explains that the same neurons will fire regardless of whether you are watching an activity or doing it. These “mirror neuron[s are] formed by two main regions: the rostral part of the inferior parietal lobule and the ventral premotor cortex”. This is observed regardless of whether the activity is seen, hear or thought of. However, only a small part of the mirror neurons fire when a sound attached to an action (“e.g., ripping a piece of paper”).
This is really important in the learning process; it “transforms visual information into knowledge”. Without having someone physically moved into position, people can have the “computer program” for the action downloaded by oberservation. In fact, one gets to feel the action. Baldissera et al. (2001) found that a flexor and extensor reflex occurred when observing someone opening and closing a hand. In other words, the exact muscles that needed to be used in opening and closing the hand where “pinged”.
The epic part is that this works between species, if we see any animal eat, our mirror neurons for eating will fire. However, the action must not be unique a species; “observation of barking did not produce any frontal lobe activation”. Finally, , the coolest part of Mirror-Neurons is that “listening to sentences describing actions engages visuo-motor circuits subserving action representation”. So, if I where to say jump, the neurons involved in jumping would fire.