Here’s why women may have better hearing than men
The old adage is that moms have eyes in the back of their heads, but a new study shows that women in general may also have more sensitive hearing.
The study, recently published in the journal Scientific Reports, sought to examine the correlation between multiple factors — including gender, age and region, among others — and hearing sensitivity.
Patricia Balaresque, Ph.D., at the Centre for Biodiversity and Environmental Research in Toulouse, France, led a team of scientists to conduct hearing tests on 448 individuals from 13 global communities in Ecuador, England, Gabon, South Africa and Uzbekistan.
The results show that hearing sensitivity is primarily influenced by gender and environment, followed by age and left versus right ear.
“Our findings challenge existing assumptions and highlight the need to consider both biological and environmental factors when studying hearing,” Balaresque said in a press release.
Scientists measured hearing sensitivity using transient-evoked otoacoustic emissions (TEOAE), which assess the cochlea’s ability to produce and transmit an acoustic response after sound stimulation.
The cochlea is a fluid-filled, spiral-shaped cavity in the inner ear that converts sound waves into electrical impulses that the brain can interpret, medical sources state.
By analyzing TEOAE profiles, researchers gained valuable insights into how the cochlea responds to external auditory stimuli.
To calculate hearing sensitivity, a small device played a clicking sound into the ear of test subjects and then recorded the tiny sounds the inner ear sent back in response, the study findings detailed.
These returning signals, which are created by cells in the cochlea, provide a reliable indication of how sensitive the ear is to sound.
The researchers then examined the signals, including how strong they were (measured in decibels, a unit used to convey the relative intensity or loudness of a sound) and which frequencies the ear responded to most strongly.
They also compared variations based on a variety of factors, including subjects’ sex, age, ear being tested, and the type of environment they lived in.
Throughout the testing, women consistently showed a higher sensitivity, by an average of two decibels across all populations sampled.
“We were surprised to find that women had two decibels more sensitive hearing across all the populations we measured, and this accounted for most of the variations between individuals,” said study co-author Turi King, professor and director of the Milner Centre for Evolution at the University of Bath, in the release.
“This could be due to different exposure to hormones during development in the womb, due to men and women having slight structural differences in cochlear anatomy.”
Women also perform better in other hearing tests and speech perception, which indicates that their brains are better at processing information, according to King.
“We don’t really know why this might be, but given the detrimental effect of noise on overall health, such as sleep quality and increased cardiovascular disease, having more sensitive hearing in noisy environments may not always be a good thing,” she added.
While differences in age were also a factor in hearing sensitivity (with old age linked to worse hearing), it was less pronounced than the differences between sexes.
Other findings in the study included the way ecological environments can impact hearing sensitivity.
For those in urban environments, hearing profiles shifted to higher frequencies, which could be due to the constant low hum of traffic and city noises in urban environments, scientists hypothesized.
The greatest contrast was found between groups living in high-altitude populations versus tropical environments, with the latter having a higher sensitivity to hearing.
This could be a result of living in areas with fewer humans in the environment, or an inherited trait from the sort of wild environment where vigilance is essential for survival, the researchers noted.
Professor King added, “We know that humans are continuing to evolve, so the next question is whether our hearing is able to change in response to different environments generally or whether there are genetic adaptations involved.”
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