These common sounds can impair your learning, according to new psychology research

New research suggests that certain sounds associated with illness—like coughing and sniffling—may interfere with learning by distracting people during educational tasks. In a recent study published in Evolutionary Psychological Science, participants who were exposed to these types of sounds while watching a statistics lecture and taking a quiz performed significantly worse than those who heard no distracting sounds. The findings suggest that the human brain may be particularly sensitive to cues that signal the presence of disease, which could divert attention away from other tasks.

The researchers designed the study to explore how the behavioral immune system—a set of psychological mechanisms that help people detect and avoid potential sources of infection—might influence learning. While the behavioral immune system is typically associated with responses like disgust or social avoidance, prior research has also shown it can affect perception, memory, and attention.

For instance, people tend to rate bodily sounds like sneezing or coughing as especially aversive, even if there is no actual threat. The researchers wanted to test whether these kinds of pathogen-related sounds might also reduce the brain’s capacity to retain unrelated academic information.

“I conducted an experiment back in 2018 which found that people will perceive the taste of water differently when they believe that water came from a dirty source (e.g., a bathroom sink). That laid the foundation for realizing that pathogen-prevalent details alter our perception. I began wondering what other senses may be affected by this phenomenon,” said study author Carey J. Fitzgerald, an assistant professor of psychology at the State University of New York Oneonta.

“Then, a few years ago, when I was teaching a class in the winter, I noticed a lot of coughing, sneezing, and sniffling from my students when they were taking a test – something normal when teaching in upstate New York. Most of those sounds, however, were met by other students looking up from their tests and visually searching for whomever was the source of those sounds. This led me to think about how distracting those sounds were, and made me wonder if they were affecting my students test scores.”

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To test this idea, Fitzgerald and his two co-authors — Robert F. Lockamyeir and Richard A. Kauffman Jr. — recruited 89 undergraduate students from an introductory psychology course at a small university in the northeastern United States. All participants were between the ages of 18 and 24, and none had taken a statistics course before. The participants were randomly assigned to one of three experimental conditions: a control group, a neutral sound group, or a pathogen sound group.

Each participant watched the same seven-minute video lecture about z-scores and frequency distributions. Afterward, they completed a short distractor task and then took a 20-question quiz based on the lecture content. The quiz included both factual recall questions and applied math problems involving z-score calculations.

Participants in the control group completed the tasks in silence. In the neutral sound condition, students heard background noises like keys jingling, papers shuffling, and a backpack zipper being zipped. In the pathogen sound condition, students heard periodic coughing and sniffling. All sounds were presented at the same volume—about 70 decibels—and occurred every 15 seconds during both the lecture and the quiz. The coughs and sniffles were real recordings taken from a researcher who had influenza B.

All participants used headphones to listen to the audio and completed the tasks alone in a small room. After finishing the quiz, students in the sound conditions were asked whether they noticed the sounds and how distracting or loud they found them. As expected, participants in both sound conditions reported hearing the sounds, and there were no significant differences in how loud or distracting they rated them. In both cases, the average rating of loudness was high, and the level of distraction was rated as moderate.

“Participants did not perceive the pathogen-prevalent sounds as being louder or more distracting than the neutral sounds,” Fitzgerald told PsyPost. “This means that the participants were probably not consciously aware of the distracting effects that these sounds produced.”

Despite the similar ratings, participants who heard the coughing and sniffling performed significantly worse on the quiz than those in the control group. On average, the pathogen sound group answered about 10 out of 20 questions correctly, while the control group averaged nearly 14 correct answers. This represents a performance drop of roughly 17%. The pathogen sound group also scored slightly lower than the neutral sound group, who averaged around 12 correct answers, although that difference was not statistically significant.

There was no significant performance difference between the neutral sound group and the control group, which suggests that the sounds themselves weren’t inherently distracting. Instead, the researchers believe that the specific nature of the pathogen-related sounds triggered a deeper cognitive response, drawing attention away from the task at hand.

This idea aligns with cognitive load theory, which holds that people have limited mental resources for processing information. Learning new academic concepts—what researchers call “biological secondary knowledge”—requires more cognitive effort than basic, instinctive tasks like recognizing faces or speaking a native language. If part of the brain’s attention is diverted to assessing a possible health threat in the environment, fewer resources are available to focus on learning. The result may be decreased retention of new information.

The findings also support prior research on the behavioral immune system. When people encounter signs of illness in their surroundings—whether visual, tactile, or auditory—they may unconsciously shift attention to evaluating those cues. This could serve an adaptive purpose by helping people avoid infection, but it may also come at a cost, especially in modern environments where performance on tasks like schoolwork or office assignments is essential.

“Our data suggests that people pay greater attention to pathogen-prevalent details – probably as a means of keeping us safe and healthy – and because attention is limited, this enhanced attention toward pathogen-prevalent details may come at the cost of decreased attention toward other things, resulting in lower quiz scores,” Fitzgerald explained. “In other words, students may be better able to ignore distracting sounds that are neutral compared to distracting sounds that are indicative of pathogens.”

There were some limitations to the study. “This experiment was conducted with individual students who were being tested in an enclosed room with no one else around,” Fitzgerald noted. “Therefore, we cannot conclude with certainty that this effect generalizes to real-world classroom settings with multiple students taking a test at the same time. We hypothesize that this effect will be stronger in classroom settings, but our experimental method does not allow us to know that.”

Despite these limitations, the results offer new insight into how the human mind responds to potential health threats in the environment. Even when people are not consciously aware of feeling distracted, pathogen-related sounds may subtly impair their ability to focus and learn. This could have implications for how educators and employers think about background noise and performance. It also highlights the influence of evolutionary responses on modern cognition, especially in situations where attentional resources are limited.

“My colleagues and I hope to design a similar follow-up study that utilizes a real-world classroom setting, but that type of design is proving to have a lot of confounding variables to control for,” Fitzgerald said. “We are currently designing an experiment to examine whether pathogen-prevalent images (e.g. rotten food) elicit greater attention compared to similar images that are not indicative of pathogens (e.g. that same food but not rotten).”

“I conducted this experiment with my two colleagues – Dr. Robert Lockamyeir and Dr. Richard Kauffman. They were immensely helpful with the design and execution of this study.”

The study, “Pathogen‑Prevalent Auditory Distractions may Differentially Impact Retention of Newly Learned Information,” was published April 7, 2025.