{"id":827002,"date":"2025-02-14T11:13:38","date_gmt":"2025-02-14T17:13:38","guid":{"rendered":"https:\/\/newsycanuse.com\/index.php\/2025\/02\/14\/though-mostly-useless-wiggling-ear-muscles-work-hard-to-hear\/"},"modified":"2025-02-14T11:13:38","modified_gmt":"2025-02-14T17:13:38","slug":"though-mostly-useless-wiggling-ear-muscles-work-hard-to-hear","status":"publish","type":"post","link":"https:\/\/newsycanuse.com\/index.php\/2025\/02\/14\/though-mostly-useless-wiggling-ear-muscles-work-hard-to-hear\/","title":{"rendered":"Though Mostly Useless, Wiggling Ear Muscles Work Hard to Hear"},"content":{"rendered":"

They wiggle, though they don\u2019t do much else. That\u2019s what we\u2019ve long thought about the auricular muscles \u2014 the useless ear muscles that once helped our ancient ancestors hear. But recent research in <\/span>Frontiers in Neuroscience<\/span><\/a> reveals that these muscles are still trying hard to help us, activating during difficult listening situations.<\/span><\/p>\n

\u201cThere are three large muscles [that] connect the auricle [the outer ear] to the skull and scalp,\u201d said Andreas Schr\u00f6er, a study author and a neuroscientist at Saarland University in Germany, in a <\/span>press release<\/span><\/a>. \u201cThese muscles, particularly the superior auricular muscle, exhibit increased activity during effortful listening tasks.\u201d<\/span><\/p>\n

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Read More:<\/span> <\/span>5 Vestigial Body Parts Found in Humans<\/span><\/a><\/span><\/p>\n

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Made For More Than Wiggling<\/span><\/h2>\n<\/p>\n

In modern humans, auricular muscles aren\u2019t all that useful. We use them to wiggle our ears (or, some of us do), and that\u2019s about all. (Wiggling, as it turns out, isn\u2019t a universal skill.) But millions of years ago, our distant ancestors employed these muscles to move their ears around, twisting and turning them towards sound.<\/span><\/p>\n

\u201cThe exact reason these became vestigial is difficult to tell, as our ancestors lost this ability about 25 million years ago,\u201d Schr\u00f6er said in the release. \u201cOne possible explanation could be that the evolutionary pressure to move the ears ceased because we became much more proficient with our visual and vocal systems.\u201d <\/span><\/p>\n

While we can\u2019t contort our ears in the same way today, some of us sure can wiggle them, suggesting that these muscles are still active. Testing their abilities in <\/span>2020<\/span><\/a>, Schr\u00f6er and a team of researchers demonstrated that these muscles activated during listening tasks that featured sounds from different directions. But what about during difficult listening, when several sounds occur at once? <\/span><\/p>\n

To determine whether the activity of these muscles depends on the difficulty of the task, Schr\u00f6er and a team turned to electromyography, a method that uses electrodes to monitor the electrical activity in muscle tissues. Their results revealed that the more difficult the task, the more active the muscles, at least for the superior auricular muscles.<\/span><\/p>\n

\u201cThis suggests that these muscles are engaged not merely as a reflex but potentially as part of an attentional effort mechanism,\u201d Schr\u00f6er said in the release, \u201cespecially in challenging auditory environments.\u201d<\/span><\/p>\n

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Read More: <\/span>How Similar Are Humans and Monkeys? <\/span><\/a><\/span><\/p>\n

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When Hearing Is Hard<\/span><\/h2>\n<\/p>\n

To arrive at their results, the researchers enlisted the help of 20 hearing participants. Applying electrodes to their auricular muscles, the team measured their muscle activity as they listened to an audiobook and a podcast at the same time. The audio played from separate speakers, placed in front of the participants or behind, and each participant listened to 12 trials, separated into three different levels of difficulty. <\/span><\/p>\n

The audiobook was a lot louder than the podcast in the easy trials, and the speakers\u2019 voices were distinct. But in the moderate and difficult trials, the audiobook was only a little louder than the podcast, and the speakers\u2019 voices were similar.<\/span><\/p>\n

As the difficulty level of the task increased, so, too did the activity of the superior auricular muscles. Though they remained relatively inactive during the easy and medium trials, the difficult trials saw a surge in their activity. <\/span><\/p>\n

According to the researchers, their activation also correlated with the participants\u2019 self-assessments and comprehension scores. When the participants were asked to assess the amount of listening effort that they expended in the trials, they reported their effort increased with trial difficulty. And when they were asked to take tests on the audiobook\u2019s content, their scores declined in step with the incline in the difficulty of the task.<\/span><\/p>\n

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Effort in Listening<\/span><\/h2>\n<\/p>\n

Further research is required to confirm the team\u2019s results, and to conclude whether the activity is tied to any actual improvements in listening (though Schr\u00f6er says that it probably isn\u2019t). <\/span><\/p>\n

\u201cThe ear movements that could be generated by the signals we have recorded are so minuscule that there is probably no perceivable benefit,\u201d said Schr\u00f6er in the press release. \u201cOur auriculomotor system probably tries its best after being vestigial for 25 million years, but does not achieve much.\u201d <\/span><\/p>\n

Though it isn\u2019t likely that this activity helps hearing, it could help hearing research, as the superior auricular muscles could serve, the team says, as an indicator for increased levels of effort in listening.<\/span><\/p>\n

\u201cInvestigating the possible effects of muscle strain itself or the ear\u2019s miniscule movements on the transmission of sound is something we want to do in the future,\u201d Schr\u00f6er said in the release. \u201cThe effect of these factors in people with hearing impairments would also be interesting to investigate.\u201d<\/span><\/p>\n

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Read More: <\/span>How Did Humans Evolve?<\/span><\/a><\/span><\/p>\n

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Article Sources<\/span><\/h2>\n<\/p>\n

Our writers at<\/span> Discovermagazine.com<\/span><\/a> use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:<\/span><\/p>\n