Resume: A study shows that children as young as three years old can understand the intentions of others using active mirror neurons. This discovery highlights the early development of the “resonance” system, crucial for social cognition.
Researchers found that the mylohyoid muscle of preschoolers is activated when anticipating goal-directed actions. These findings could aid in the early diagnosis of conditions such as autism spectrum disorder.
Key Facts:
- Early understanding: Three-year-olds use mirror neurons to understand the intentions of others.
- Muscle activation: The mylohyoid muscle is activated during observation of goal-directed actions.
- Diagnostic potential: May help detect social cognition deficits in autism at an early stage.
Source: Catholic University
At age three, children are able to understand others, and “mirror” those they are with to imitate and anticipate their intentions. They can do this thanks to the sophisticated neurofunctional architecture needed to understand the intentions of others, the mirror neurons, which are already active at this age.
It is the result of a study published in the prestigious journal PNASled by the collaboration between Giacomo Rizzolatti of the University of Parma, the scientist who discovered mirror neurons, and the research group composed of Cinzia Di Dio, Laura Miraglia and Giulia Peretti and coordinated by Antonella Marchetti, director of the psychology department at the Università Cattolica, Milan campus.
“This is a very important discovery,” explains Professor Marchetti, “because it shows that even at such a young age, children are equipped with the ‘resonance system’ made up of mirror neurons, which are the building blocks on which a more complex and articulated understanding of the social world will be built with development and experience.”
Although preschoolers are capable of planning goal-directed motor actions, their understanding of the intentions of others performing motor tasks has not been thoroughly investigated until now.
The group from Università Cattolica, together with Professor Rizzolatti, investigated the ability of preschool children to organize a sequence of motor actions by understanding the intention behind the sequence of actions of another individual.
To verify this ability, the researchers measured activation of the mylohyoid muscle, which is involved in opening the mouth, while the children picked up a piece of food to eat or a piece of paper to put in a container.
During the grasping of the food, activation of the mylohyoid muscle began several milliseconds before the action was completed. The muscle was not activated during the grasping of the paper, suggesting that there was a planned sequence of motor events directed toward the goal of the action.
Even when the children observed an experimenter performing the same grasping tasks, the mylohyoid muscle was activated during observation of the eating task.
However, Professor Marchetti explains: “We found that muscle activation occurs more slowly compared to older children, aged 6 to 9 years (investigated in previous studies), which is supported by the emergence of more advanced cognitive processes.”
According to the authors, the results suggest that understanding the motor intentions of others is a developing ability in preschoolers.
“In conclusion,” Professor Marchetti emphasizes, “the current data provide further support to the evidence regarding the different stages of child development in this area, in continuity with research in infants showing an early attunement to goal-directed motor actions.
“Overall, these results are also relevant from the perspective of early diagnosis, for example in the case of children with autism spectrum disorder, because they would allow to perform a psychophysical instrumental assessment of a possible deficit in understanding intentions and a possible impairment of fundamental precursors for the development of social skills,” she concludes.
About this neurodevelopmental research news
Author: Nicola Cerbino
Source: Catholic University
Contact: Nicola Cerbino – Universita Cattolica
Image: The image is attributed to Neuroscience News
Original research: Closed access.
“Action chains and understanding of intentions in 3- to 6-year-old children” by Giacomo Rizzolatti et al. PNAS
Abstract
Action chains and intention understanding in children aged 3 to 6 years
In intentional behavior, the ultimate goal of an action is crucial in determining the entire motor sequence. Neurons have been described in the inferior parietal lobule of monkeys that, in addition to encoding a specific motor action (e.g., grasping), have their discharge modulated by the ultimate goal of the intended action (e.g., grasping-to-eat).
Many of these ‘action-limited’ neurons have mirroring properties that respond to observation of the motor action they encode, provided it is embedded in a specific action.
Thanks to this mechanism, the observers have an internal copy of the whole action before its execution and can thus understand the agent’s intention. The chained organization of motor actions has been demonstrated in schoolchildren.
Here we investigated whether this organization is already present in very young children. For this we recorded EMG of the mylohyoid (MH) muscle in the children aged 3 to 6 years. The results showed that preschoolers, like older children, possess the chained organization of motor actions in execution.
Interestingly, compared to older children, they have a delayed ability to use this mechanism and infer the intentions of others from observation.
Finally, we found a significant negative association between the age of the children and the activation of the MH muscle during the grasping-to-eat phase in the observation condition. We interpreted it, provisionally, as a sign of immature control of motor actions.