the mirror neuron system (social cognition)

• mirror neurons

  • a set of specialised neurons that are activated when we observe the motor actions of others, but are also activated when we perform motor actions ourselves
• Rizzolatti et al (monkeys)

  • rizzolatti noted that the same neurons in a monkey's motor cortex became activated when:
  • monkeys observed a researcher reaching for his lunch
  • the monkey itself reached for food
• intentions of others

  • Gallese and Goldman = suggested that mirror neurons respond not just to observed actions but to intentions behind behaviour
  • we need to understand the intentions of others in order to interact socially
  • research on mirror neurons suggests we actually stimulate the action of others in our own brains and => experience their intentions through our mirror neurons
• mirror neurons underlie perspective-taking and ToM

  • mirror neurons give us a neural mechanism for experiencing , and hence understanding other people's perspectives and emotional states
• human social evolution

  • Ramachandran = suggested that mirror neurons have shaped human evolution, in particular how we have evolved as a social species
  • mirror neurons enable us to understand intention, emotion and perspective
  • these are fundamental requirements for living in large groups with the complex social roles and rules (both of which characterise human culture)
• understanding of autism (ASD)

  • ASD = associated with problems related to social-cognitive abilities (such as difficulty with perspective-taking, understanding intention, emotion and ToM)
  • it follows that people with ASD might have a poor mirror neuron system
• 'broken mirror' theory of ASD

  • Ramachandran and Oberman = proposed the 'broken mirror' theory of ASD
  • according to this theory = ASD develops due to neurological deficits (including dysfunction in the mirror neuron system)
  • such dysfunction prevents a child imitating and understanding social behaviour in others
  • researchers have observed that, in infancy, children who are later diagnosed with ASD typically mimic adult behaviour less than children with no diagnosis
  • this may demonstrate innate problems with the mirror neuron system
• strength = support for role of mirror neurons

  • Haker et al = demonstrated using brain scans that Broadmann's Area 9 (part of the brain rich in mirror neurons) is involved in contagious yawning (simple example of human empathy)
  • mouras et al = found when men watched heterosexual pornography - activity in the pars opercularis was followed by sexual arousal
  • presumably mirror neurons allowed the viewer to experience what they were watching (perspective-taking)
  • means mirror neurons may have a role in empathy and perspective-taking
• limitation = difficulties involved in studying the system in humans

  • studies where electrodes are inserted in animal brains are not ethical in humans and the animal findings don't generalise to human cognition
  • brain scanning (like Haker's) can be used but doesn't measure individual cells
  • => there is no gold standard for measuring mirror neuron activity in humans and no direct evidence for mirror neuron activity in humans
• strength = application to explaining ASD

  • Hadjikhani = reported that the pars opercularis (linked to perspective-taking) had a smaller-than-average thickness in people with ASD
  • scanning has also shown lower activity levels in regions of the brain believed to be associated with high concentrations of mirror neurons compared to neurotypical brains
  • suggests that a cause of ASD may be related to the mirror neuron system
• counterpoint to application to explaining ASD

  • the findings are not reliable - according to a review of 25 studies by Hamilton, evidence in this area is highly inconsistent
  • means that there may not be a link between ASD and mirror neuron activity after all
• extra evaluation

  • Maranesi et al = found specific mirror neurons in monkeys' motor cortex fired according to the position and angle from which experiments gestured - shows physical perspective is encoded by mirror neurons
  • BUT = Soukyana Bekkali et al = concluded that there is only weak evidence linking mirror neurons to social cognition in humans
  • means that the idea that mirror neurons underlie perspective-taking in social situations remain unproven