Responses of mirror neurons in area F5 to hand and tool grasping observation

Abstract

Mirror neurons are a distinct class of neurons that discharge both during the execution of a motor act and during observation of the same or similar motor act performed by another individual. However, the extent to which mirror neurons coding a motor act with a specific goal (e.g., grasping) might also respond to the observation of a motor act having the same goal, but achieved with artificial effectors, is not yet established. In the present study, we addressed this issue by recording mirror neurons from the ventral premotor cortex (area F5) of two monkeys trained to grasp objects with pliers. Neuron activity was recorded during the observation and execution of grasping performed with the hand, with pliers and during observation of an experimenter spearing food with a stick. The results showed that virtually all neurons responding to the observation of hand grasping also responded to the observation of grasping with pliers and, many of them to the observation of spearing with a stick. However, the intensity and pattern of the response differed among conditions. Hand grasping observation determined the earliest and the strongest discharge, while pliers grasping and spearing observation triggered weaker responses at longer latencies. We conclude that F5 grasping mirror neurons respond to the observation of a family of stimuli leading to the same goal. However, the response pattern depends upon the similarity between the observed motor act and the one executed by the hand, the natural motor template.

Individual and social learning processes involved in the acquisition and generalization of tool use in macaques

“…Do they also have an understanding of the action made with the tool? Clearly, when monkeys are exposed to the observation of an action which they master because of a prolonged sensorimotor training, mirror neurons in their premotor cortex fire during observation of actions performed with the tool [50]. More interestingly, after prolonged visual exposure to an action performed by an experimenter using a tool, some premotor mirror neurons have been shown to respond specifically to the observation of tool actions [47].…”

Measuring Human-Robot Interaction Through Motor Resonance

“…In fact, these works showed that while the observation of a human grasping induced neural firing, in contrast the grasping performed with a mechanical tool (a pair of pliers) did not induce the same activation. However, recent findings [35,36] demonstrated that after prolonged training with a tool also tool-object interactions become effective in triggering F5 response. Therefore, the presence of a mechanical device is not sufficient per se to eliminate motor resonance.…”

The motor way: Clinical implications of understanding and shaping actions with the motor system in autism and drug addiction

“…Singleneuron recording studies in nonhuman primates have indicated that the parieto-frontal MNs discharge when one performs a specific action and when one observes another individual performing the same action (Bonini et al, 2010;Fogassi et al, 2005). A previous study indicated that the majority of grasping MNs in area F5 discharged irrespective of whether grasping was achieved using the right or the left hand, or a precision, whole-hand, or even oral grip (Rochat et al, 2010;Umiltà et al, 2008). Using Bnormal pliers^(i.e., opening and then closing the fingers to grasp) and Breverse pliers( i.e., closing and then opening the fingers to grasp), Umiltà et al (2008) showed that MNs discharged according to the motor goal (i.e., the meaning, to grasp), regardless of the type of pliers.…”