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http://www.ted.com/talks/vs_ramachandran_the_neurons_that_shaped_civilization.html



Introduction


Our clip is a short, educational lecture about the relatively recent discovery of Mirror Neurons by Giacomo Rizzolatti. In short, mirror neurons are two derivatives of normal neurons from the motor and touch domains. Their function is to fire and engage with vicarious motor activities and touch in others. Our clip poses that mirror neurons are the basis of social interaction, imitation learning and empathy.

The clip, delivered by esteemed neuroscientist Vilayanur Ramachandran, was posted on the “TEDtalks” commune section of the non-profit organization TED's website. Filmed in 2009 and uploaded in January 2010, the clip explains the new and exiting nature of the discovery. Explaining, in a basic and accessible way, how mirror neurons were discovered, what they do, and their broad implications.

Our research further explores the neuroscientific research supporting the discovery of mirror neurons, building on Ramachandran's brief, interest provoking overview. We uncovered that the body of research surrounding Rizzolatti's original discovery has grown extensively, giving mirror neurons an adequate empirical backing.

Mirror neurons are of significance as they may, as Ramachandran poses, be responsible for the rapid evolution of the human race. Their role in empathetic understanding, learning and language, all key to our social structure, makes them of key interest in the on-going quest to better understand ourselves. Our research systematically goes through the Motor mirror neuron, Somatosensory mirror neuron and two implications, imitation learning and language

Neuroscientific context


Motivated movement - The motor mirror neuron

This specialised class of brain cells known as mirror neurons are equally activated by the execution of action as well as the perception of another individual’s actions. Its discovery was made by a team of neurophysiologists, led by Giacomo Rizzolatti, during their research of the human brain using Macaca Nemestrina, a species of monkey. With surgically implanted electrodes, activity in the brain of these macaque monkeys, who were seated quietly at the time, were detected when Rizzolatti's colleague, Vittorio Gallese, reached out for an object. The static sound emitted from the recording device of brain activity, signalled a discharge from area F5 of the premotor cortex in these monkeys - an area where neurons coding for the one specific motor behaviour, such as grasping, is innumerable (Iacoboni, 2008).

Mirror neurons comprise two subsets – strictly congruent and broadly congruent mirror neurons. Strictly congruent mirror neurons respond to the sight of specific executed actions that must also exist in the individual's motor repertoire. For instance, the cells that fire when a monkey grasps a piece of fruit with a precision grip (with thumb and index finger), will only fire at the sight of a comparably small object requiring an identical grip, but will not fire at the sight of a whole banana as this would require a full hand grip (Ioacoboni, 2008). This finding was further extended to include studies in humans in an attempt to acquire evidence in favour of mirror neurons in the human brain. In his research of the mirror neuron property, Luciano Fadigo (mid 1990s) exposed his subjects to one of two conditions - they either observed an experimenter perform grasping actions or attended to an unrelated activity, which in this case was the dimming of light. Results show that muscular twitches (an indication for neural activity) were more prominent at the sight of the grasping actions in comparison to the observation of the unrelated dimming light.

On the contrary, broadly congruent mirror neurons do not fire at the sight of an identical executed action but rather, at the action that accomplishes a similar goal. The equal firings of neurons in macaque monkeys at the grasping action of food, as well as the witness of another individual obtaining food orally exemplifies this property of mirror neurons. This goal-driven property is further supported by Harold Bekking's (1980s) study with preschoolers, whereby the children engaged in an activity with an adult, with the instruction "do what I do". The adult touched his left or right ear with either an ipsilateral movement or a contralateral movement. Throughout the experiment, the children had succeeded in touching the correct ear but had failed to imitate the action with the correct hand movement. The failure to imitate such hand movement suggests that to the children, the intended goal of the action was more important than the action itself.

Animal instinct to Empathetic understanding - The somatosensory mirrror neuron

Systems involved in touch are shared circuits. They allow qualitative understanding of another's experience by recruiting neural circuits activated in first-person engagement. Keysers and Gazzola (2006) outline three distinct shared circuits, those for motor, sensations and emotions. Despite separate circulatory however, their role in social cognition suggests complementary action; as social interaction incorporates multiple dimensions.

Sensation
The Somatosensory Cortices S1 and S2 provide the affective component of vicarious sensation,evidenced by correlations relating Somatosensory activity to heightened empathy scores (Kaas and colleagues, 2010). An FMRI study by Keysers and Gazzola (2006) provided evidence that the somatosensory cortices allow vicarious touch. The study comprised of two experimental conditions; physical touch and perception of touch, and a control which received neither. The result showed similar activation of S2 in experimental conditions. Thus, S2 adds a tactile component to empathetic affective processing, modulated by the Anterior Insula and Rostral Cingulate Cortex.

Another aspect of sensation is empathetic pain - affective pain elicited vicariously. Singer (2004) evidences empathetic pain in her FMRI study, where participants were subjected to pain, and told another person was receiving that pain. The results showed similar activation of the Anterior Insula and Cingulate Cortex across situations. This explains why approximately one third of people report feeling pain correspondingly on their body when witnessing it.

Emotions
The Insula lobe associates gustatory and olfaction with other modalities, registering disgust and causing visceral responses. Pierre Krolak-Salmon and colleagues (2006) illustrated the system as a shared mirror circuit, with the anterior section of the lobe reacting selectively to facial expressions of disgust. Individuals with damage to their Insula Lobe are impaired at perceiving and experiencing revulsion, further revealing its importance in the emotion disgust.

The empathy neuron has immense implications. Without them, one could still perceive emotionality in others, however this perception would be “destitute of emotional warmth” (Sinigaglia & Rizzolatti, 2006). The empathy neuron therefore allows an individual to engage in a more qualitative experience, which is the prerequisite for empathy (Sinigaglia and Rizzolatti, 2006).

Spread our skills - Implication one; language

Two subcategories of mirror neurons fire when listening to action sounds and observing communicative gestures made by others. These comprise a substrate from where sophisticated forms of communication evolved: given the anatomical and functional homology of the monkey premotor cortex and Broca's area in humans (Fogassi1 & Ferrari, 2007, 136-141)

The mimetic capacities of F5 (location of firing of mirror neurons in brain) and Broca’s area fabricate closed systems relative to diverse motor spectrums present in that area (hand, mouth and larynx) (Rizzolatti & Arbib, 1998, 188-194). The first open system evolving human speech was a manual gestural system that exploited the observation and execution matching system, conclusively paving the way for the evolution of the open vocalization system - speech.

Recent studies by Arbib (2005a and 2005b) suggested that gestural communication progressed to ‘protosign’- where the mirror system moves from understanding transitive action to intransitive use of action for communication. Thus protosign served as a scaffold for protospeech, and is therefore a fundamental intermediate interlocked with the evolution of language.

Picture_1.jpg
Figure 1. Model of the influence of protosign upon the mirror system and its impact on the evolution of language (Arbib, 2005a, p.30).

F5 and Broca’s areas have neural structures for controlling oro-laryngeal, oro-facial and brachio-manual movements, whilst furthermore endowing machinery that link action perception and action production. Savage-Rumbaugh, Shanker, & Taylor, (1998) studied a Bonobo, who had an enormous vocabulary, based on pointing to symbols on a keyboard, supplemented with manual gestures. Indistinct to this, his ability to construct meaningful sequences was limited to two or three ‘‘words”, leading to the likely conclusion that the human capacity to communicate is beyond that of other primates due to the progressive evolution of the mirror system in its globalism.

Speech is a gestural practice rather than an acoustic one, as Rizzolatti and Arbib (1998) established that the mirror system operates according to the same principles proposed by the motor theory of speech perception (Liberman, Cooper, Shankweiler, & Studdert-Kennedy, 1967) - speech sounds are perceived in terms of their form of production, rather than as acoustic elements. Furthermore leading to the endpoint that mirror systems function as precursors to the development of speech and thus language.

In summary, mirror neurons are responsible for many components of social interaction. Mirror motor neurons give us the ability to instantly understand the motor skills of others, enabling new and innovative skills to be learned quickly across the generation. Empathy neurons enable us to understand the emotionality of others, without this our ability to relate to one another would be severely compromised. Finally, the notion that mirror neurons underscored human language, one of the most unique accomplishments of our species, highlights how their function has altered who we are, and how we live. This research is still ongoing, however people are highly interested in mirror neurons as it has been suggested that mirror neurons may prove to be for neuroscience what DNA was for biology (Iacoboni, 2008)

Analysis


This media item is sourced from TED, a non-profit organisation devoted to the spreading of ideas, from the domains of Technology, Entertainment and Design. This organisation is evocative of a global commune, through features such as online ‘TEDtalks’(as has been used here). These talks are accessible to individuals beyond the English-speaking world, through the amalgamation of subtitles, transcripts and the ability for any talk to be translated by volunteers worldwide. This accessibility is radically enhanced for: the hearing-impaired, those speaking limited English, for search engines (which can now index the full transcript of a talk), and for the sizeable audience of non-English speakers worldwide. More primarily this item is intended towards individuals with some form of scientific understanding, as its purpose is to convey a deeper level of knowledge upon this subject matter, which is significantly advanced by some degree of associated knowledge.
TED is classified as a trustworthy organisation due to its applicability globally and the extensive third party selection process involved in investigation of publishment of individual’s ideas in terms of their level of relativity and form of representation.

Dr Ramachandran is a professional neuroscientist known for his inspirational work in the fields of behavioural neurology and psychophysics. For this reason he is referred as “The Marco Polo of neuroscience” (Dawkins, 2002, para.2). His findings have been published in multiple journals, media sources, and have been awarded on numerous occasions. Therefore to this day he is referenced on countless occasions, a fact significant enough to prove the accurate validity of his findings. In addition to the veracity of Ramachandran himself, is the inclusion of reference to scientific, peer-reviewed studies that contribute to the current neuroscientific understanding of mirror neurons. Ramachandran establishes a lot of his conclusions from those of Rizzolatti, the founder of mirror neurons, bringing a more extensive level of veracity to the work Ramachandran presents.

As an alternate view there are some aspects of Ramachandrans speech that hinder the veracity of the complete function of mirror neurons. Through simplification of content (in order to present most adequately to his audience), Ramachandran portrays mirror neurons as being the sole neuronal connection resulting in the development of imitation and action. In thorough analysis this is not so accurate, as especially in areas like language, mirror neurons are an intermediate system acting in conjunction with other mechanisms, which in union lead to the later development of some form of functionality. Fogassi1, L., & Ferraril, P. F. (2007) explains that one capacity that may have driven the evolution of language was mental time travel. The production of language and the emergence of linguistic devices to signal time and space seem precisely tuned to the requirements of communicating events, real or imaginary. Therefore mental time travel and the act of language coevolved, to comprise the distinctive structure of the human mind.

Ramachandran makes reference to the factual status of early human culture depicting the actuality of evolved human behaviour, whilst linking the influence mirror neurons had upon this development. The ability to reference the influence of mirror neurons upon such a factual established foundation transmits an enhanced degree of validity upon the role of these neurons. In addition Ramachandran explains how mirror neurons “made evolution Lamarckian instead of Darwinian”. This constructs Ramachandran in a biased manner, as there is evidence to suggest the theory of evolution being either Lamarckian or Darwinian. Conclusively the validity behind the functionality of mirror neurons in evolution is not certified by all perspectives.

Search strategy



This topic was chosen during the first few weeks of semester, we chose to search using TED because it draws information from credible, innovative researchers from around the world. As we had watched another video from neuroscientist Vilayanur Ramachandran in our tutorials we were particularly interested when we found another of his lectures on TED. This brought us to this video on mirror neurons. We subsequently searched several videos and scientific journals related to mirror neurons. Through this we uncovered a significant neuroscientific basis for the overview presented by Ramachandran. We felt particularly drawn to this clip because of it incorporated elements of neuroscience, psychology and broad social implications. Additionally the video was posted in 2010, signifying the recency of mirror neurons in the field on neuroscience We felt drawn to this recency because of its potential for future research possibilities.

This resource was particularly rewarding because in conjunction to its neuroscientific overview, it also extended to societal implications. Thus, the item afforded us the opportunity to extend our research into how aspects of neuroscience can shed light on social issues.

References



Arbib, M. A. (2005a). From monkey-like action recognition to human language: An evolutionary framework for neurolinguistics. Behavioral and Brain Sciences, 28, 105–168.

Arbib, M. A. (2005b). Interweaving protosign and protospeech: Further developments beyond the mirror. Interaction Studies, 6, 145–171.
Australian Institute of Policy and Science. (2000). A Neuroscientist’s Quest for What Makes Us Human. Retrieved from http://www.aips.net.au/aipstv/a-neuroscientists-quest-for-what-makes-us-human/

Fogassil, L., & Ferraril, P. F. (2007). Mirror Neurons and the Evolution of Embodied Language. Current Directions in Psychological Science,16(3), 136-141

Garrels. R S, (2004), Imitation, Mirror neurons, & Mimetic Desire: Convergent Support for the Work of Rene Girard, Fuller Theological Seminary, California, pp6-8.

Iacoboni, M. (2008), Mirroring People. New York: Douglas & McIntyre.

Iacoboni, M. (2009), Imitation, Empathy and Mirror neurons, The Annual Review of Psychology,USA, 60: 657-659.

Keyers, C., Gazzola, V. (2006). Towards a unifying theory of social cognition. Progress in Brain Research, 156.

Keyers, C., Gazzola, V., Kaas, J. (2010) Somatosensation in social perception. Nature, 11.

Liberman, A. M., Cooper, F. S., Shankweiler, D. P., & Studdert-Kennedy, M. (1967). Perception of the speech code. Psychol. Rev, 74(5), :431-61.

Oztop. E, Kwato. M, Arbib. M, (2006), Mirror neurons and Imitation: A Computationally guided Review, Neural Networks,Elsevier,Japan, 19: 259-261.

Rizzolatti, G., Graighero, L. (2004) The Mirror-Neuron System. Annual Reviews in Neuroscience, 27, 169-92

Rizzolatti, G., Sinigaglia, C. (2008).Mirrors in the brain. Oxford, NY.

Rizzolatti, G., & Arbib, M. A. (1998). Language within our grasp. Trends Neurosience, 21(2), 188–194.

Savage-Rumbaugh, S., Shanker, S.G., & Taylor, T.J. (1998). Apes, language and the human mind. Oxford: Oxford University Press.

Skoyles. R J, (2008), Why Our Brains cherish Humanity: Mirror neurons and Colamus Humanitatum, Avances enPsicologia Latiniamericana,Colombia, 26: 99-101.