Mns - mirror neuron system PDF

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mirror neuron system...

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Neurons are nerve cells that transmit information throughout the brain using electrical impulses. Mirror neurons are a specific type of neuron that ‘fires’ when an animal performs and action, but also when the animal watches an action performed by someone else. E.g. chuck a pen at rumanah, salmons neuron will also fire, even though his just an observer. Following their research with monkeys, DI Pellegrino et al, and Rizzolatti et al, established the following:  Mirror neurons only fire if they is an interaction between the movement of an effectors (hand on mouth) and an object( e.g the monkey reaches for or picks up a banana)  Mirror neurons do not fire in response to random movements by hand on mouth with no target object.( e.g the monkey makes a reaching movement with no banana in sight).  Different mirror neurons respond to actions initiated by hands and mouths  The observer monkey does not have see to see the movement. Mirror neurons will also fire when an observer monkey hears an actor monkey pick up a peanut and crack the shell open- that is, they respond to the meaning. Mirror neurons are located all over the brain- depending on what the issue is e.g. if it’s an action thing it involves pre frontal motor cortex. Only happens when the action has some feeling with it. Even if it’s not a deliberate action, we can still feel it, e.g. someone tripping and falling, if the action has no consequence or no emotion your neuron wont fire. Mirror neuron helps us understand the reason and situation. It helps us understand and feel how they feel and think about the circumstances of the situation. Helps us understand other people. The theory argues that all this social cognition is biological. Ramachandran and Oberman (2006) have proposed the; broken mirror’ theory of ASD. This is the idea that neurological deficits including dysfunction in the mirror neuron

system prevent a developing a child imitating and understanding social behaviour in others. This manifests itself in infancy when children later diagnosed with ASD typically mimic adults behaviour less than others. Later, problems with the MNS lead to difficulties in social communication as children fail to develop the usual; abilities to read intention and emotion in others. Mirror neurons appear to play a role in several areas of social cognition, including action, understanding, empathy and imitation. When we see someone carry out an action (such as picking up an apple) our mirror neurons are activated as if we had personally picked up the apple. The neural ‘mirroring’ action could enable the observer to identify the goals or intention they would have if personally carrying out the behaviour, and then mentally attribute this to the person they are observing. Brain scans have shown that observing someone in pain activated the same brain systems that are activated when you feel pain yourself (Rizzolatti et al, 2006). So we directly experience the same sensation as the other person, which is the foundation of empathy. The mirror neuron system in humans is loess activated in people who score low on empathy scales (Gozzola et al), and in participants with autism (Oberman et al). Mirror neurons also facilitate imitation. People with normal functioning mirror neuron cans simply and automatically copy movement that they have seen someone perform. Without a functioning mirror neuron system, we would need to consciously analyse a movement before attempting to control it. Some studies have suggested people with autism have difficulty imitating other people, especially when complex movements re involved. Icaboni et al argue that problems with imitation could lead to mental retardation that co-occurs with autism 75% of the time. Evaluation: A defective mirror neuron system has been agued to be the basis of autistic problems with social communication and interaction. However, research has provided mixed support for the implication of mirror neuron deficits in autism. Some studies have provided support for the claim that people with autism have mirror neuron deficits. Others (Dinstein et al 2010) have contradicted this. Dinstein et al compared FMRI scans of ten autistic adults with 10 age-matched

non autistic controls who observed and then copied a series of hand gestures (thumb up, high five). The researchers found no significant difference in the average mirror neuron response between the 2 samples. This shows the mirror neuron doesn’t cause deficits. Evaluation: Ramachandran 2011, suggested that mirror neurons are so important that they have effectively shaped human evolution. The uniquely complex special interactions we have as humans require a brain system that facilitates an understanding of intention, emotion and perspective. Without these cognitive abilities we could not live in the large groups with the complex social rules and rules that characterise human culture. Ramachandran suggests that mirror neurons are absolutely key to understanding the way humans have developed social species.

Evaluation: A major source of evidence concerning mirror neurons comes from the study of mirror neurons in children suffering from autistic-spectrum disorder (ASD). ASD is associated with problems with all social cognitive abilities. Ramachandran and Oberman have proposed the ‘broken mirror’ theory of ASD. This is the idea that neurological deficits including dysfunction in the MNS prevent a developing child imitating and understanding social behaviour of others. This manifests itself in infancy when children later diagnosed with ASD typically mimic adult behaviour less than others. Later, problems with the mirror neuron system lead to difficulties in social communication as children fail to develop the usual abilities to read attention and emotion in others....