Cues to intention bias action perception toward the most efficient trajectory

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Perception

Background:

• Humans naturally interpret actions as intentional and predict energy-efficient movements.
• Perceptual representations of observed actions are biased towards expected efficient trajectories.
• The role of intentionality cues in guiding these efficiency expectations remains under investigation.

Purpose of the Study:

• To investigate whether predictions of efficient action depend on the perceived intentionality of the stimulus.
• To determine the influence of semantic and motion cues of intentionality on action perception.

Main Methods:

• Participants observed videos of efficient and inefficient reaching actions performed by an actor.
• Intentionality cues were manipulated by replacing the hand with a ball or removing biological motion.
• Participants reported the perceived hand position after the hand disappeared mid-trajectory.

Main Results:

• Judgments of inefficient actions were biased towards efficiency expectations, consistent with prior research.
• Removing intentionality cues (non-agentive ball, lack of biological motion) substantially reduced these perceptual biases.
• Perceptual biases are significantly modulated by the presence of intentionality cues.

Conclusions:

• Action perception is guided by expectations of efficiency, triggered by intentionality cues.
• Semantic and motion cues signaling intentionality are crucial for invoking efficiency-based predictions.
• Understanding intentionality is fundamental to how we perceive and interpret others' actions.