Human Ear Muscles Activate During Effortful Listening, Study Finds

Recent research has revealed that small muscles in the human ear, once thought to be vestigial, become active when people focus intently on sounds. These muscles, known as the superior auricular muscles, are located above the ear and are responsible for subtle ear movements. While most people cannot consciously move their ears, the muscles still play a role in auditory processing. ^[1]

Understanding the Superior Auricular Muscles

Humans possess three auricular muscles: the anterior, superior, and posterior auricular muscles. These muscles connect the ear to the skull and scalp, allowing for minor ear movements. In many animals, such as cats and dogs, these muscles enable significant ear mobility, which helps in detecting and localizing sounds. In humans, however, they have become less prominent over time and are generally described as vestigial. ^[2]

Study Methodology

A research group at Saarland University in Germany investigated how auricular muscles behave during auditory challenges. Using electromyography (EMG), they measured electrical activity in the superior and posterior auricular muscles of twenty participants with normal hearing. Subjects were asked to listen to an audiobook while background noise was gradually increased to simulate difficult listening conditions. ^[3]

Findings

The researchers found that the superior auricular muscles showed increased electrical activity when participants strained hardest to distinguish sounds in noisy environments. This indicates that the muscles are engaged when the brain exerts more effort to process auditory information. In addition, the posterior auricular muscles—responsible for pulling the ear backwards—were more active when sounds originated from behind, suggesting that different ear muscles respond to specific sound directions. ^[4] 

"The hearing aid would then boost the sound level for sounds coming from that direction," Hackley told Live Science in an email.

Implications

The study challenges the long-held belief that auricular muscles in humans are entirely without function. Their activation during effortful listening implies that they may contribute to auditory processing in subtle ways. These insights may have practical applications in hearing science. For example, integrating auricular muscle activity into auditory prosthetics or hearing aids could help create devices that respond more effectively to a user’s listening effort.

Conclusion

The work by Saarland University researchers provides fresh evidence that human auricular muscles, though diminished compared to those of animals, still play an active role in listening. While humans no longer swivel their ears like other mammals, the brain continues to recruit these muscles during difficult auditory tasks. Continued research could expand our understanding of auditory processing and guide improvements in hearing technologies.

References

1. Schroeer, Andreas. "Electromyographic Correlates of Effortful Listening in the Human Auriculomotor System." Frontiers in Neuroscience, 2025. https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2024.1462507/full.

2. “‘A Neural Fossil’: Human Ears Try to Move When Listening, Scientists Say.” The Guardian, January 31, 2025.https://www.theguardian.com/science/2025/jan/31/neural-fossil-human-ears-move-when-listening-scientists-say.

3. “Vestigial Human Ear-Wiggling Muscle Actually Flexes When We're Straining to Hear.” Live Science, January 31, 2025. https://www.livescience.com/health/anatomy/vestigial-human-ear-wiggling-muscle-actually-flexes-when-were-straining-to-hear.

4. “Ancient Ear Muscles Reactivate When We Struggle to Listen.” Neuroscience News, January 31, 2025. https://neurosciencenews.com/ear-muscle-hearing-28399/.

_MSM