In our own image? Emotional and neural processing differences when observing human-human vs human-robot interactions.

Area of Science:

• Neuroscience
• Human-Robot Interaction (HRI)
• Social Cognitive Neuroscience

Background:

• Human-robot interactions (HRI) are increasingly significant, yet neural correlates of eeriness in response to social robots are under-researched.
• The 'uncanny valley' describes negative feelings towards robots resembling humans but not perfectly, but its neural basis remains unclear.

Purpose of the Study:

• To investigate the neural correlates of eeriness experienced during human-robot interactions (HRI).
• To compare brain activity during human-human interactions (HHI) and HRI processing.
• To identify brain regions associated with social-cognitive strategies in HHI versus HRI.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to measure brain activity in 26 participants.
• Participants viewed video clips of both human-human interactions (HHI) and human-robot interactions (HRI).
• Analysis focused on activity within the mentalizing network and its relationship to perceived eeriness.

Main Results:

• Both HHI and HRI activated the mentalizing network, but with distinct patterns.
• HHI showed increased activity in the left temporal-parietal junction (implying situation-specific mentalizing).
• HRI recruited the precuneus and ventromedial prefrontal cortex (VMPFC) (suggesting script-based reasoning), with VMPFC activity parametrically tracking eeriness, a potential neural correlate of the uncanny valley.

Conclusions:

• Understanding social interactions relies on the type of agents involved, influencing distinct neural pathways.
• The study identifies specific neural mechanisms underlying impression formation in HRI.
• Findings highlight challenges in developing acceptable humanoid robots due to the uncanny valley phenomenon.