Tiny Facial Twitches Reveal Mice’s Thought Processes, Raising Questions About Human ”Intellectual Privacy”
Lisbon, Portugal – scientists at the Champalimaud Foundation in Lisbon have made a groundbreaking discovery: subtle, unintentional facial muscle movements in mice can reveal their cognitive strategies with surprising accuracy, mirroring brain activity adn perhaps offering a non-invasive window into thought processes. The research, published in Nature Neuroscience (Cazettes, F. et al., 10.1038/s41593-025-02071-5, 2025), utilizes machine learning to analyze facial expressions alongside neuron activity in the secondary motor cortex – an area previously identified as key to mouse decision-making.
The team filmed the faces of mice during experiments, finding that these minute facial expressions were just as indicative of their chosen strategy as direct recordings of brain activity. “As for the decision-making strategy, small, unintentional muscle movements in the mouse vision were just as revealing as the registered brain activity,” the study reports.
Perhaps even more surprisingly, the researchers observed consistency across individuals. “The resistance of the results from Mouse to Mouse was even more surprising: a certain facial expressions represented the same cognitive strategy for various individuals,” explained co-author Davide Reato. This suggests a link between specific thinking patterns and corresponding facial expressions, echoing the established connection between facial cues and emotions.
This non-invasive approach – relying solely on video recording of facial expressions - has significant implications. The researchers suggest the technology could potentially be adapted for use with humans, given our well-known ability to “Read emotions on our face.” Though, they also caution against the potential for misuse of such biometric technology, urging the growth of “effective legal requirements to protect human ‘intellectual privacy.'”
The study opens new avenues for understanding the neural basis of decision-making and raises critical ethical questions about the future of mind-reading technologies.
