Monkey See, Monkey Do

Image Citation: [1]

Written by Thanmay Kumar ‘27

Edited by Thomas Wang ‘26

Have you ever seen someone yawn and suddenly felt the urge to yawn yourself? Or have you ever flinched or winced when someone got hurt in a movie scene? Often, we see actions and automatically translate them into our own movements without consciously thinking. Well, this may be a product of the brain trying to mirror the experiences of the people around us. A specialized group of neurons called mirror neurons play a key role in this process and help us imitate others, understand their intent, and may form the neurological basis for empathy [2].

Mirror neurons were first discovered in the early 1990s by a team of Italian neuroscientists at the University of Parma led by Giacomo Rizzolatti. While studying the motor cortex of macaque monkeys, they found that certain neurons activated both while a monkey performed an action and also when the monkey watched a similar action being performed [3]. This unexpected finding laid the groundwork for research into the mirror neuron systems of the brain and would reveal their versatile role spanning from imitation and learning to empathy and higher-order social cognition.

Researchers soon discovered that mirror neurons integrate visual and auditory information about others' actions with the observer's own motor representations [4]. This integration allows the observer to understand and predict others' actions by mapping observed movements onto their own motor system. By simulating an action internally, these neurons can help us mirror what others do and feel.

Brain imaging studies identified the premotor cortex of monkeys, an area of the brain involved in planning motor actions, as the location of the mirror neurons [2]. In humans, homologous areas, including parts of the brain that bordered the motor cortex, were similarly activated during imitation activities.

Imagine you see someone pick up a glass of water. You can predict exactly what will happen next: they’re going to take a sip. Essentially, mirror neurons make this possible by activating the same circuits that would fire when you perform that action yourself. Whether anticipating the movements of other drivers on the road or understanding the intentions behind someone else’s actions, motor neurons help us actively predict actions before they occur [5].

While mirror neurons were initially discovered in relation to motor command, researchers later uncovered the extensive role they play in emotional intelligence. Neural circuits in emotional processing regions of the brain activate both when we experience emotions and when we observe them in others [6]. We all experience this vividly: watching someone fail or embarrass themselves can make you physically cringe and when someone laughs, your brain activates the same facial and respiratory muscles in your own body. The emotional aspect of empathy is mediated through mirror neurons that fire an emotional response within you to mirror suffering or joy you see in the world around you.

The mirror neuron system is also incredibly important in childhood development and language learning [7]. When babies hear words, mirror neurons help them stimulate the mouth movements needed to reproduce those same sounds. In fact, studies show that listening activates mirror motor neurons in the speech areas of the brain, implying that a baby's brain may be ‘practicing’ to talk months before it can speak. 

On the other hand, new research implicates mirror neuron dysfunction with a wide range of childhood developmental disorders, including autism spectrum disorder (ASD). Many children with autism have difficulty imitating facial expressions, gestures, and speech while also having difficulties empathizing with others [8]. Underactive motor neurons may explain why individuals with ASD struggle to map observed actions onto their own motor systems and may misinterpret emotional expression [9, 10]. Furthermore, since mirror neurons help us predict intentions based on movement, dysfunction would also cause increased difficulty in social interactions and interpretation of nonverbal gestures, body language, and eye contact. It is also important to remember that science is constantly evolving and while the MNS hypothesis may provide a theoretical framework for understanding certain aspects of autism, research is still ongoing and theories are constantly being updated.

The study of mirror neurons has tremendous implications for reshaping how we approach childhood development, education, medicine, and mental health. Our understanding of the way humans learn through imitation and mirroring may help society better support childhood development. From targeted therapies for individuals with ASD to motor rehabilitation for stroke recovery patients, mirror neurons may be key to understanding the fundamental principle of learning: monkey see, monkey do.

References

1. Snipette [Internet]. 2023. A Reflected Mind. Available from: https://snipettemag.com/a-reflected-mind/

2. Napolitano A. Study casts new light on mirror neurons. Nature Italy [Internet]. 2021 Aug 24; Available from: https://www.nature.com/articles/d43978-021-00101-x

3. Rizzolatti G, Fadiga L, Gallese V, Fogassi L. Premotor cortex and the recognition of motor actions. Cognitive Brain Research. 1996 Mar;3(2):131–41.

4. Lahav A, Saltzman E, Schlaug G. Action Representation of Sound: Audiomotor Recognition Network While Listening to Newly Acquired Actions. J Neurosci. 2007 Jan 10;27(2):308–14.

5. Jeon H, Lee SH. From Neurons to Social Beings: Short Review of the Mirror Neuron System Research and Its Socio-Psychological and Psychiatric Implications. Clin Psychopharmacol Neurosci. 2018 Feb;16(1):18–31.

6. Bastiaansen JACJ, Thioux M, Keysers C. Evidence for mirror systems in emotions. Philos Trans R Soc Lond B Biol Sci. 2009 Aug 27;364(1528):2391–404.

7. Simpson EA, Murray L, Paukner A, Ferrari PF. The mirror neuron system as revealed through neonatal imitation: presence from birth, predictive power and evidence of plasticity. Philos Trans R Soc Lond B Biol Sci. 2014 Jun 5;369(1644):20130289.

8. Vivanti G, Rogers SJ. Autism and the mirror neuron system: insights from learning and teaching. Philos Trans R Soc Lond B Biol Sci. 2014 Jun 5;369(1644):20130184.

9. Chan MMY, Han YMY. Differential mirror neuron system (MNS) activation during action observation with and without social-emotional components in autism: a meta-analysis of neuroimaging studies. Molecular Autism. 2020 Sep 29;11(1):72.

10. Oberman LM, Hubbard EM, McCleery JP, Altschuler EL, Ramachandran VS, Pineda JA. EEG evidence for mirror neuron dysfunction in autism spectrum disorders. Cognitive Brain Research. 2005 Jul 1;24(2):190–8.

11. Rizzolatti G, Fabbri-Destro M, Cattaneo L. Mirror neurons and their clinical relevance. Nat Rev Neurol. 2009 Jan;5(1):24–34.