Scientists show humans can “catch” fear from a breathing robot

New research provides evidence that humans can physically absorb fear from a robot through the sensation of touch alone. The study indicates that holding a robot simulating rapid, fearful breathing causes a person’s heart rate to rise, offering evidence that emotions can spread through tactile cues. These findings were published in the scientific journal Emotion.

People frequently reach out to touch or hold others when they feel frightened. A startled child might cling to a parent, or friends might grab each other’s arms while watching a horror movie. Usually, this physical contact serves to reduce distress and downregulate negative emotions. However, the individuals being touched are often experiencing intense emotions themselves.

Psychologists have established that emotions can spread from one person to another. This process is known as emotion contagion. It is typically studied through visual cues, such as observing facial expressions or body language. Less is known about how tactile sensations contribute to this transmission when visual cues are absent or ignored.

When people and animals are afraid, their breathing rate typically increases and becomes deeper. This physiological change alters the movement of the chest cavity. Because breathing patterns are physically perceptible through touch, they might serve as a distinct channel for communicating emotional states.

This physiological indicator is not specific to humans. Many animals exhibit changes in their breathing when they are frightened. Cats and dogs are commonly used for emotional support, and they also display respiratory changes during high-arousal states. This suggests that breath patterns could be a widely generalizable mechanism for communicating emotion across species.

Free daily newsletter

“A large body of research shows that physical touch from others can downregulate fear and stress, such as when people hold a loved one’s hand during a scary movie, or when a child clings to their parent when they’re frightened. However, we were interested in whether touch always has this calming effect,” said study author Zachary Witkower, an assistant professor of psychology at the University of Amsterdam.

“Specifically, we asked what happens when the entity you are touching is itself expressing fear. To address this gap, we built plush robots with motorized ribcages that expanded and contracted to simulate breathing, and examined participants heart rate as they held on to this robot. Consistent with our hypotheses, in one condition where the robot engaged in accelerated breathing, participants exhibited a significantly elevated heart rate.”

The researchers recruited 103 undergraduate students from the University of British Columbia for the experiment. Most participants were women, and the average age was approximately 20 years. The team constructed a specialized soft robot for the study. Using a robot allowed them to isolate breathing movements from other social cues like sweating or muscle tension.

The robot was roughly the size of a small cat and covered in plush fur. This design encouraged comfortable tactile interaction similar to holding a pet. The researchers avoided a human-like appearance to prevent the discomfort often caused by imperfect human replicas.

Inside the robot, a motorized plastic ribcage allowed the researchers to control the expansion and contraction of its body. The internal structure used wishbone-shaped pieces to create a ridged, spine-like feel. A motor connected to these ribs with fishing line simulated the physical sensation of breathing.

Participants were seated and instructed to hold the robot against their chest with both arms. They were connected to a heartbeat detector attached to a finger. While holding the robot, participants wore headphones and watched a series of video clips on a computer screen.

The viewing session began with a neutral, boring video of a snail crossing a plank to establish a baseline. This was followed by a frightening scene from the movie The Shining. The researchers measured the participants’ heart rates continuously throughout the video presentations.

The participants were randomly assigned to one of three experimental conditions regarding the robot’s behavior. In the “no-breathing” condition, the robot remained still throughout the entire experiment. This condition served as an inactive control group.

In the “stable-breathing” condition, the robot simulated a calm, resting human breathing rate of about 14 breaths per minute. This movement remained consistent throughout the session. This served as an active control to ensure movement alone was not the cause of arousal.

In the “accelerated-breathing” condition, the robot initially breathed calmly but then sped up significantly during the scary video clip. The rate increased to 30 breaths per minute to simulate hyperventilation associated with fear. This design allowed the researchers to compare how different tactile signals influenced the participants’ physiological reactions.

The researchers found that the robot’s behavior influenced how participants interpreted the situation. Those holding the robot with the accelerated breathing pattern rated the robot as feeling more afraid than those in the other groups. This confirms that the tactile cues were successfully communicating an emotional state.

Physiological data revealed that participants in the accelerated-breathing group experienced a substantial increase in their own heart rates while watching the scary video. The physical sensation of the robot’s rapid breathing appeared to amplify their bodily response to the fear-inducing stimulus.

In contrast, participants holding the robot with stable, calm breathing did not experience a significant increase in heart rate during the frightening clip. The steady rhythm provided by the robot appeared to buffer the participants against the physiological stress of the video. This supports the idea that touch can help downregulate emotion, provided the entity being touched is calm.

Those holding the non-breathing robot showed a small increase in heart rate. This increase fell between the other two groups. It was statistically smaller than the reaction seen in the accelerated-breathing group.

The researchers analyzed the timing of these heart rate changes. The data showed that the increases in the accelerated-breathing group aligned with the moments the robot was hyperventilating. This synchronization suggests a direct link between the tactile perception of breathing and the observer’s physiological arousal.

“Our results suggest that humans can physiologically ‘catch’ fear through touch—even from a robot,” Witkower told PsyPost. “Touching a robot that simulated fearful, rapid breathing heightened participants’ heart rate during a scary film, whereas touching a robot with calm, stable breathing reduced heart rate. This indicates that our emotional responses are sensitive not just to touch itself, but to the emotional signals conveyed through that touch.”

“The effects were modest but reliable, which is typical for psychophysiological responses measured in controlled laboratory settings. Importantly, the findings demonstrate proof of principle: even minimal, abstract cues like simulated breathing can meaningfully shape emotional experience.”

Participants also completed surveys about their own emotional states after the experiment concluded. But these self-reports generally did not show significant differences in subjective fear between the groups. This discrepancy might be because the surveys were taken minutes after the interaction ended.

By the time the participants filled out the questionnaires, their heart rates had largely returned to baseline. However, participants in the accelerated-breathing condition did report lower levels of positive affect compared to the other groups. This suggests a lingering negative impact on their mood.

As with all research, there are some limitations to consider. The sample consisted entirely of undergraduate students. This demographic may not represent the general population. Older adults or young children might respond differently to tactile cues from a robot.

The study relied on heart rate as the primary measure of physiological arousal. While heart rate is a strong indicator of fear, it does not provide a complete picture of the autonomic nervous system. Future research could include measures of the participants’ own breathing rates to see if they subconsciously matched the robot’s rhythm.

The robot used in the study was clearly artificial and animal-like rather than human-like. It remains unclear if the same effects would occur with a robot designed to look and feel like a human. The context of the interaction was also strictly controlled within a laboratory environment.

“A key caveat is that the robot did not look human—it was a simple plush object with a moving ribcage,” Witkower noted. “This suggests that emotional contagion through touch does not require anthropomorphic appearance, but it also means we should be cautious in generalizing to all forms of human–robot interaction.”

These findings open new avenues for the design of social robots and therapeutic devices. Robots that simulate calm breathing could effectively help reduce anxiety in clinical or home settings. Haptic feedback simulating rapid breathing could be used in virtual reality to increase immersion and excitement.

“Future work will explore how these effects generalize to other emotions, longer interactions, and more naturalistic settings,” Witkower explained. “We are also interested in how individual differences and context shape whether robotic touch amplifies or dampens emotional experiences.”

“As robots and wearable technologies become more integrated into daily life, understanding how their physical behaviors influence human emotion will be increasingly important—both for designing supportive technologies and for avoiding unintended emotional consequences.”

The study, “Human Psychophysiology Is Influenced by Physical Touch With a ‘Breathing’ Robot,” was authored by Zachary Witkower, Laura Cang, Paul Bucci, Karon MacLean, and Jessica L. Tracy.