An international team of researchers, led by scientists from the University of Bologna, has uncovered the neural mechanisms behind the behavior that prompts you to yawn when someone else yawns in front of you. This phenomenon, called “copycat behavior,” facilitates social interaction and cohesion and allows people to spontaneously interact with others.
The study, published in the Proceedings of the National Academy of Sciences in July, reveals new insights into how the brain regulates this behavior, opening up new avenues for clinical and therapeutic applications. The research was conducted at the Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna.
“Our results open up new avenues for understanding how to manipulate brain plasticity to increase or decrease imitative behavior,” explains Alessio Avenanti, professor in the Department of Psychology at the University of Bologna, who coordinated the study. “This could lead to therapeutic applications to improve cognitive performance in patients with neurological disorders and social dysfunction disorders.”
What is auto-imitation?
Imitative behavior underlies many complex social interactions and can affect interpersonal relationships. Furthermore, spontaneous imitation can have serious consequences and often needs to be controlled, especially if you are a goalkeeper trying to save a penalty kick, you must prevent yourself from imitating the movements of the forward player.
“Spontaneous imitation is a widespread behaviour in everyday life: when we see someone yawn, we immediately feel the need to do the same, or when we notice that our speech or facial expressions adapt to those of a friend we are talking to,” says Sonia Turrini, a research fellow at the Department of Psychology at the University of Bologna and lead author of the study. “Understanding the mechanisms behind this phenomenon could therefore provide new perspectives on social behaviour.”
Advanced brain stimulation technology
The motor system performs many roles. It helps us move and move objects, as well as assisting us in verbal and non-verbal communication (gestures). Despite the variety of movements we perform, motor control is often considered simple, perhaps reflecting the fact that movements appear easy and largely unconscious. However, even simple movements require significant computation to coordinate the action of multiple muscles. The motor system in our body is known to be constantly involved in the automatic imitation of actions, facial expressions, and speech.
Specific regions in the frontal parts of the brain, such as the prefrontal cortex, motor cortex, and primary motor cortex, contribute to movements in unique ways. However, the precise and potential roles of different cortical circuits within the motor system remain to be elucidated.
To shed light on this, the researchers used an advanced, non-invasive brain stimulation technique known as “coupled cortical-cortical associative stimulation,” which Professor Avenanti’s research group helped develop. The new technique involves stimulating specific areas of the brain and recording the response that this stimulation produces in another area, thus revealing how these areas interact within the brain.
For his part, Professor Avenanti explains – according to the Eurek Alert website – “Thanks to this stimulation technique, it was possible to target the mechanisms of plasticity in the brain’s neural map, which is the comprehensive map of neural connections in the brain. By temporarily enhancing or inhibiting communication between different areas of the motor system, it was possible to determine the causal role of the different circuits in facilitating or inhibiting the phenomenon of spontaneous imitation.”
Experience
The study included 80 healthy participants, divided into 4 groups, each group underwent a different stimulation protocol. Each participant performed two behavioral tasks before and after the stimulation treatment: a voluntary imitation task and a spontaneous imitation task.
The goal was to test whether manipulating connectivity between specific brain regions—specifically the ventral motor area, the supplementary motor area, and the primary motor cortex—affects voluntary, automatic imitation.
The results showed that different circuits in the motor system serve distinct and separable social functions, and that the direction of stimulation and the target region differentially affect the neural circuits involved in the imitation process.
“We saw that strengthening the connection between the ventral motor area and the primary motor cortex increases the tendency to spontaneously imitate others’ behavior, while weakening it has the opposite effect,” says Sonia Torrini. “In contrast, the supplementary motor cortex seems to play a role in the cognitive control of the motor system: strengthening its connection with the primary motor cortex actually increases the ability to avoid imitation when it is contextually inappropriate.”