Mirror neurons somehow receive excitatory inputs from visual regions of the brain that respond to the sight of other people’s actions. Through these connections, they “translate” the visual language into the motor language of the monkey’s own actions. (Location 368)
The broadly congruent mirror neurons might thus be particularly important for new actions, the details of which you have never performed. (Location 402)
What this finding means is that mirror neurons appear to combine the sight, the sound and the execution of an action. They are “trilingual.” The most important finding, however, was that mirror neurons are selective in all three modalities. (Location 434)
Paradoxically, the major hurdle to understanding the human mind is the obsession for rationality of the minds of the scientists that study it. The second hurdle is computers. Together, they have created the vision of a brain that processes all information in a conscious, logical and abstract way–much as ordinary computers do. The discovery of mirror neurons changed this vision. (Location 441)
The scientists’ abstract rational vision was further cemented into the minds of people through the trap of what you could call the “brain-computer-fallacy.” (Location 453)
Of course, comparing our brains to computers is a fallacy. Both leopards and Ferrari’s are fast, but should we therefore assume that a combustion engine must be hidden somewhere in the leopard? Unfortunately, many cognitive scientists have more or less consciously fallen into a similarly wrong line of thinking. (Location 459)
The monkey’s method differs fundamentally from the way a computer would predict behavior. Computers don’t grasp for or eat fruit; therefore they cannot use their own behavior to predict that of animals. Monkeys, on the other hand, routinely perform most of the actions other monkeys might. They can map the behavior of their fellows onto their own body and actions. The prediction is no longer based on a set of propositional rules specifically acquired to predict the behavior of other individuals, but uses the machinery that governs the observer’s own actions and body to run a simulation of what the observer would do next, and the predicted behavior is then attributed to the observed animal The classical divide between self and other and between body and mind becomes fuzzy and permeable in this process. The mind-function of predicting another’s behavior is now based on the neural representation of the observer’s own body and actions, it becomes “embodied,” i.e., founded and grounded in the bodyi. The other organism is thus represented in parts of the brain of the observer that were thought to be dedicated to dealing with the monkey’s self. (Location 496)
Using the self as a simulation of other individuals is a very economical and elegant form of computation, because instead of requiring an explicit set of rules about others, it utilizes the machinery that specializes in doing ones own actions to also predict the actions of others. The discovery that the brain actually uses this form of embodied simulation changes our view of the brain. For the first time, social cognition is no longer just any old form of computation but a very specific one that relies on the resemblances between organisms. In now makes sens why we find it so much easier to predict the behavior of the giggling couple tiptoeing toward the bedroom at a party than that of dice–because we are people, not dice. (Location 505)
instead of postulating a rich set of propositional rules that allow us to deduce intentions from behavior, the brain of the monkey maps the behavior of other individuals onto its own, thereby activating a sense of the observed actions through an embodied simulation that relies more on the machinery of motor control than abstract thinking. (Location 537)
fMRI is a powerful method for measuring brain activity, based on the fact that if we use a particular part of the brain, this part needs more oxygen. To satisfy this demand, the body sends more blood to this particular brain region. By placing people into a strong magnetic field, it is possible to localize and measure this increase in blood flow, thereby indirectly measuring brain activity. (Location 638)
Roy and Marco found that several neurons in this motor region where not only active while the patient grasped small objects but also while viewing movies of other people grasping similar objects. Several other neurons responded both while the patient was asked to make certain facial expressions and while viewing the facial expressions of others[10]. Altogether these experiments now provide uncontestable evidence that humans have mirror neurons too[11]. (Location 713)
Studies using fMRI and positron emission tomography (PET) scans have shown precisely where in the brain activity is induced both during the sight/sound and the execution of actions. Two of the regions involved, the premotor cortex and the posterior parietal lobe, are the same two areas where mirror neurons have been found in monkeys. A third area of common activation is in the visual cortex of the temporal lobe. (Location 720)
But unlike mirror neurons in the premotor and parietal lobe, neurons in this visual area do not respond while the monkey executes actions. Hietanen and Perrett examined the neurons that respond to the sight of a hand moving upwards and found that when the monkey lifted his own hand, only half of these neurons responded strongly to the sight[12]. If the neurons were only visual, they should have responded equally to both sights. In a way, it makes sense that they do not. If I move my hand, I do not need to be very aware of the sight of a hand moving, since I already know that I am doing it. To achieve this down-regulation of my own movements, the brain would need to send a copy of the motor signal that moves my hand to the temporal lobe and selectively inhibit those neurons with corresponding visual properties. The process requires energy and may be what augments the blood flow in the visual cortex while participants in the fMRI studies execute actions. (Location 725)
An interesting property of this cancellation is that it requires the inverse process of that used in mirror neurons. Mirror neurons translate a sensory stimulus (an action I see) into a motor vocabulary (the action I can do). However, to cancel the consequences of our own movements, the brain needs to transform a motor action I’m planning to do into the sensory vocabulary of what I will see, in order to subtract it from a visual description. The brain thus translates back and forth between motor and sensory vocabularies, which also has the advantage that if our movement does not look like what we expected, the process will nullify the aspects we expected, but leave the ones we have failed to predict uncanceled and salient, providing a valuable “error” message. (Location 738)
The overall mirror circuitry is thus composed of a core circuit of premotor and parietal areas containing mirror neurons, and a third area in the temporal lobe, intimately linked to the other two areas. This area in the temporal lobe provides visual input to the core mirror areas and in return receives information about motor intentions that it uses to cancel expected visual consequences. The (Location 747)
Together, these studies suggest that when we watch the actions of others, the visual signal travels from the eye through a series of visual processing steps that lead to the activation of visual neurons in the temporal lobe where neurons respond to the sight of bodily movements and facial expressions. From there the signal goes to the parietal lobe and from there to the premotor cortex. Along these passages, the visual information is translated into an increasingly motor information, as in both the parietal and premotor areas mirror neurons are found that are also active during motor execution. During motor execution, the opposite flow of information appears to occur. The motor activity in premotor and parietal areas is sent backwards to the visual cortex to cancel out expected consequences of our own actions. (Location 767)
The whole action is not so much a sequential information exchange, but two brains becoming a single interconnected regulation process. What links our brains is the way mirror neurons lead both to actions and perception of the other’s actions. From the brain’s perspective, the outside world, composed of our bodies and the table, becomes an interface between our brains, and the complex information flow is so finely tuned that we can often manage not to spill a single drop of wine from the glasses on the dinner table. (Location 779)
Millions of years of evolution have come up with this exquisite system that enables us to take the great evolutionary leap of doing together what we could have never done alone. At the beginning, these interactions may have involved moving heavy objects, hunting large animals, or coordinating our defenses. Now it involves building space shuttles in teams of thousands of people, and developing our technological cultures by working together and learning from one another. (Location 784)
Nota sobre la capacidad para el trabajo colectivo. Revisar cómo lo conceptualiza Tomasello.