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The Mirror Neuron Mechanism

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  • CNR - ISTITUTO DI NEUROSCIENZE - SEDE DI PARMA
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... Another important insight of the brain is that emotions play a decisive role in the change processes of the brain and by stimulating the reward center in the brain we can activate processes that will enhance learning, habit formation and positive emotions in the brain [8]. Thirdly, the mirror neurons, which have the ability to mirroring others actions and that show that we are connected to the world and people around us International Conference "Risk in Contemporary Economy" ISSN-L 2067-0532 ISSN online 2344-5386 XX th Edition, 2019, Galati, Romania, "Dunarea de Jos" University of Galati, Romania -Faculty of Economics and Business Administration and we live related partially with the actions, emotions and intentions that we perceive from others [9]. The mirror neurons are crucial in many learning process but most important in the reading of emotions and empathy, and can activate to actions, emotions and also intentions. ...
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Functional magnetic resonance imaging (fMRI) was used to localize brain areas that were active during the observation of actions made by another individual. Object- and non-object-related actions made with different effectors (mouth, hand and foot) were presented. Observation of both object- and non-object-related actions determined a somatotopically organized activation of premotor cortex. The somatotopic pattern was similar to that of the classical motor cortex homunculus. During the observation of object-related actions, an activation, also somatotopically organized, was additionally found in the posterior parietal lobe. Thus, when individuals observe an action, an internal replica of that action is automatically generated in their premotor cortex. In the case of object-related actions, a further object-related analysis is performed in the parietal lobe, as if the subjects were indeed using those objects. These results bring the previous concept of an action observation/execution matching system (mirror system) into a broader perspective: this system is not restricted to the ventral premotor cortex, but involves several somatotopically organized motor circuits.
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In the ventral premotor cortex of the macaque monkey, there are neurons that discharge both during the execution of hand actions and during the observation of the same actions made by others (mirror neurons). In the present study, we show that a subset of mirror neurons becomes active during action presentation and also when the final part of the action, crucial in triggering the response in full vision, is hidden and can therefore only be inferred. This implies that the motor representation of an action performed by others can be internally generated in the observer's premotor cortex, even when a visual description of the action is lacking. The present findings support the hypothesis that mirror neuron activation could be at the basis of action recognition.
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The neural bases of imitation learning are virtually unknown. In the present study, we addressed this issue using an event-related fMRI paradigm. Musically naive participants were scanned during four events: (1) observation of guitar chords played by a guitarist, (2) a pause following model observation, (3) execution of the observed chords, and (4) rest. The results showed that the basic circuit underlying imitation learning consists of the inferior parietal lobule and the posterior part of the inferior frontal gyrus plus the adjacent premotor cortex (mirror neuron circuit). This circuit, known to be involved in action understanding, starts to be active during the observation of the guitar chords. During pause, the middle frontal gyrus (area 46) plus structures involved in motor preparation (dorsal premotor cortex, superior parietal lobule, rostral mesial areas) also become active. Given the functional properties of area 46, a model of imitation learning is proposed based on interactions between this area and the mirror neuron system.
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In this article we provide a unifying neural hypothesis on how individuals understand the actions and emotions of others. Our main claim is that the fundamental mechanism at the basis of the experiential understanding of others' actions is the activation of the mirror neuron system. A similar mechanism, but involving the activation of viscero-motor centers, underlies the experiential understanding of the emotions of others.
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In our daily life, we continuously monitor others' behaviors and interpret them in terms of goals, intentions, and reasons. Despite their central importance for predicting and interpreting each other's actions, the functional mechanisms and neural circuits involved in action understanding remain highly controversial. Two alternative accounts have been advanced. Simulation theory assumes that we understand actions by simulating the observed behavior through a direct matching process that activates the mirror-neuron circuit. The alternative interpretive account assumes that action understanding is based on specialized inferential processes activating brain areas with no mirror properties. Although both approaches recognize the central role of contextual information in specifying action intentions, their respective accounts of this process differ in significant respects. Here, we investigated the role of context in action understanding by using functional brain imaging while participants observed an unusual action in implausible versus plausible contexts. We show that brain areas that are part of a network involved in inferential interpretive processes of rationalization and mentalization but that lack mirror properties are more active when the action occurs in an implausible context. However, no differential activation was found in the mirror network. Our findings support the assumption that action understanding in novel situations is primarily mediated by an inferential interpretive system rather than the mirror system.
A shared neural network for emotional expression and perception: an anatomical study in the macaque monkey
  • A Kraskov
  • N Dancause
  • M M Quallo
  • S Shepherd
  • R N Lemon
Kraskov, A., Dancause, N., Quallo, M.M., Shepherd, S., Lemon, R.N., 2009. A shared neural network for emotional expression and perception: an anatomical study in the macaque monkey. Neuron 64, 922-930.
Forms of Vitality: Exploring Dynamic Experience in Psychology, Arts, Psychotherapy, and Development
  • D N Stern
Stern, D.N., 2010. Forms of Vitality: Exploring Dynamic Experience in Psychology, Arts, Psychotherapy, and Development. Oxford Univ. Press.