When you see someone yawn, a lot of times it is hard not to yawn yourself. Likewise, seeing someone get pricked with a pin on their finger often creates a phantom sensation in your own finger and it feels like you were the one who got pricked. Interestingly, the brain does something similar – the neurons that would fire when you are doing a movement also fire when watching someone else do the movement. This is a little weird but also really cool and has a whole host of implications.
These neurons were first discovered in the premotor cortex, which is important in deciding to execute an action. It communicates directly to the motor cortex, and so there is a lot of discussion about the relationship of mirror neurons and movement. However, the role of mirror neurons is controversial – much of the information we know about mirror neurons has not allowed us to succinctly determine exactly what the purpose of mirror neurons’ mimicry is. It has been speculated that these neurons have a role in motor learning, interpreting and responding to others’ behavior, language, and even empathy.
Mirror neurons do more than just activate while watching someone pick up a cup or yawn; they are thought to have a role in coding the intentions of a movement. When you’re experiencing someone moving a book or kicking a ball, it matters why they are doing this, and your mirror neurons likely have a role in understanding these intentions. This is important for social learning – mirror neurons are helpful in facilitating understanding of another. Humans are social beings, and the presence of mirror neurons in our brains could play a role in how we evolved to where we are today.
V.S. Ramachandran, a neuroscientist you might know from his work with the phantom limb phenomenon, has implicated mirror neurons in the “explosion of human mental abilities”, or the big bang of human brain evolution where the brain reached its full potential (Ramachandran, 2000). Mirror neurons could have allowed early humans to mimic the actions of their peers that helped them survive, and this ability to learn from others might have played a role in the explosion of culture that occurred in the past (Ramachandran, 2000).
Beyond social learning, mirror neurons help to facilitate motor learning. Mirror neurons are important in imitation, and through this might play a role in developing language. A baby watching an adult is bound to see them talking and will probably try to imitate. Eventually, the baby learns to talk, and imitation probably had a role in making these actions automatic and effortless. Learning by observation is one of the best and easiest ways to learn something; someone else is taking all the risks and will experience any of the consequences if what they are doing backfires. Importantly, mirror neurons are key to understanding when to do something – context really matters, and mirror neurons encode this important information.
Many researchers have brought up the idea that mirror neuron abnormality is linked with autism. Individuals with autism struggle with Theory of Mind, or understanding the mental states of others. It would make sense to implicate mirror neuron dysfunction with the struggle some autistic individuals have with social interactions; mirror neurons are likely directly related to this ability. The research into the relationship of mirror neurons and autism is complicated and very contradictory. Searching “autism and mirror neurons” on Google Scholar resulted in a list of journal articles that flipped back and forth in their findings – some were adamant about the link, while others felt strongly about the absurdity of this.
Mirror neurons are one the brain’s many enigmas; it will be interesting to see what future research uncovers regarding their purpose.
Lehrer, J. The mirror neuron revolution: Explaining what makes humans social. Scientific American: Mind. https://www.scientificamerican.com/article/the-mirror-neuron-revolut/
Ramachandran, V.S. (2000). Mirror neurons and imitation learning as the driving force behind “the great leap forward” in human evolution. Edge. http://www.edge.org/3rd_culture/ramachandran/ramachandran_index.html.