Dynamic spatial representation of self and others' actions in the macaque frontal cortex

Area of Science:

• Neuroscience
• Social Cognition
• Primate Brain

Background:

• Neuronal firing rates are modulated by object locations, but spatial tuning for biological actions and social context effects remain unclear.
• Understanding these mechanisms is crucial for embodied social cognition, including imitation and perspective-taking.

Purpose of the Study:

• Investigate how neuronal responses to actions are spatially tuned.
• Determine if social contexts dynamically alter these spatial representations.
• Examine the roles of the ventral premotor cortex (PMv) and medial prefrontal cortex (MPFC) in social cognition.

Main Methods:

• Monkeys performed a turn-taking choice task with real vs. filmed partners.
• Recorded single-neuron activity in the PMv and MPFC.
• Analyzed spatial preferences for self-actions and partner-actions across different social contexts.

Main Results:

• MPFC neurons showed diminished spatial preference for partner-actions with filmed partners compared to real partners.
• This social context-dependent modulation was also observed for self-actions in the MPFC.
• A subset of neurons in both PMv and MPFC exhibited diametrically opposite spatial preferences for self- vs. partner-actions.

Conclusions:

• The MPFC dynamically adjusts spatial representations of actions based on social relevance.
• The PMv may process spatial action information in a more context-independent manner.
• These findings suggest PMv and MPFC are involved in coordinate transformations for perspective-taking, with MPFC being more sensitive to social context.