Mirror neuron
[6][9] To date, no widely accepted neural or computational models have been put forward to describe how mirror neuron activity supports cognitive functions.
[17] In the 1980s and 1990s, neurophysiologists Giacomo Rizzolatti, Giuseppe Di Pellegrino, Luciano Fadiga, Leonardo Fogassi, and Vittorio Gallese at the University of Parma placed electrodes in the ventral premotor cortex of the macaque monkey to study neurons specialized in the control of hand and mouth actions; for example, taking hold of an object and manipulating it.
[20] A few years later, the same group published another empirical paper, discussing the role of the mirror-neuron system in action recognition, and proposing that the human Broca's area was the homologue region of the monkey ventral premotor cortex.
Recent experiments by Ferrari and colleagues suggest that infant macaques can imitate a human's face movements, though only as neonates and during a limited temporal window.
[26] Neuropsychological studies looking at lesion areas that cause action knowledge, pantomime interpretation, and biological motion perception deficits have pointed to a causal link between the integrity of the inferior frontal gyrus and these behaviours.
[43] Mukamel et al. (Current Biology, 2010) recorded from the brains of 21 patients who were being treated at Ronald Reagan UCLA Medical Center for intractable epilepsy.
The mirror neurons found were located in the supplementary motor area and medial temporal cortex (other brain regions were not sampled).
It was also significant that neurons fired before the monkey observed the human model starting the second motor act (bringing the object to the mouth or placing it in a cup).
[52] Stephanie Preston and Frans de Waal,[53] Jean Decety,[54][55] and Vittorio Gallese[56][57] and Christian Keysers[3] have independently argued that the mirror neuron system is involved in empathy.
[58][59][60][61][62][63][64] David Freedberg and Vittorio Gallese have also put forward the idea that this function of the mirror neuron system is crucial for aesthetic experiences.
[65] Nevertheless, an experiment aimed at investigating the activity of mirror neurons in empathy conducted by Soukayna Bekkali and Peter Enticott at the University of Deakin yielded a different result.
[71] This provides causal evidence for a link between pain mirror neurons, and emotional contagion and prosocial behavior, two phenomena associated with empathy, in rodents.
I also speculated that these neurons can not only help simulate other people's behavior but can be turned 'inward'—as it were—to create second-order representations or meta-representations of your own earlier brain processes.
[85] The integration of research on motor mimicry and automatic imitation could reveal plausible indications that these phenomena depend on the same psychological and neural processes.
If true, then automatic imitation can be used as a tool to investigate how the mirror neuron system contributes to cognitive functioning and how motor mimicry promotes prosocial attitudes and behavior.
Studies show that regions of the frontal and parietal lobes that extend beyond the classical mirror system are equally activated during imitation.
[98] Based on these results, some researchers claim that autism is caused by impairments in the mirror neuron system, leading to disabilities in social skills, imitation, empathy and theory of mind.[who?]
"[104] Research from 2010[99] concluded that autistic individuals do not exhibit mirror neuron dysfunction, although the small sample size limits the extent to which these results can be generalized.
[108][109][110] At the neuronal-level, in a 2015 study by Keren Haroush and Ziv Williams using jointly interacting primates performing an iterated prisoner's dilemma game, the authors identified neurons in the anterior cingulate cortex that selectively predicted an opponent's yet unknown decisions or covert state of mind.
These "other-predictive neurons" differentiated between self and other decisions and were uniquely sensitive to social context, but they did not encode the opponent's observed actions or receipt of reward.
These cingulate cells may therefore importantly complement the function of mirror neurons by providing additional information about other social agents that is not immediately observable or known.
In another study, sex-based differences among mirror neuron mechanisms was reinforced in that the data showed enhanced empathetic ability in females relative to males[citation needed].
Baland Jalal and V. S. Ramachandran have hypothesized that the mirror neuron system is important in giving rise to the intruder hallucination and out-of-body experiences during sleep paralysis.
[117] According to this theory, sleep paralysis leads to disinhibition of the mirror neuron system, paving the way for hallucinations of human-like shadowy beings.
[11] In 2008, Ilan Dinstein et al. argued that the original analyses were unconvincing because they were based on qualitative descriptions of individual cell properties, and did not take into account the small number of strongly mirror-selective neurons in motor areas.
[10] Other scientists have argued that the measurements of neuron fire delay seem not to be compatible with standard reaction times,[119] and pointed out that nobody has reported that an interruption of the motor areas in F5 would produce a decrease in action recognition.
[11] (Critics of this argument have replied that these authors have missed human neuropsychological and TMS studies reporting disruption of these areas do indeed cause action deficits[39][41] without affecting other kinds of perception.
However, despite its widespread acceptance, the proposal has never been adequately tested in monkeys, and in humans there is strong empirical evidence, in the form of physiological and neuropsychological (double-) dissociations, against the claim.
[52] Neurophilosophers such as Patricia Churchland have expressed both scientific and philosophical objections to the theory that mirror neurons are responsible for understanding the intentions of others.
In chapter 5 of her 2011 book, Braintrust, Churchland points out that the claim that mirror neurons are involved in understanding intentions (through simulating observed actions) is based on assumptions that are clouded by unresolved philosophical issues.
