Selective Hearing: Humanity's Secret Weapon

BY C KILKELLY

 

Sitting in a cramped cafe, you notice your significant other has gone eerily quiet. “Everything alright?” you ask with bated breath. “Shhhh!” they reply, “I'm eavesdropping on a juicy conversation, just keep talking so they don't catch on.”

If this scene seems familiar it's because in some shape or form we've all lived it. Selective hearing is an often unspoken, but a borderline superhero-like trait of humanity. We possess a devilishly good ability to dull our senses to what’s happening right in front of us, in favor of listening to what tantalizing talk grabs our attention in the background.

This ability was coined as “the cocktail party effect” by the British scientist, Colin Cherry, in the 1950's. Cherry noticed that people can recognize their name being uttered when they are currently speaking with another subject, even at a crowded, noisy party – or in the case of Cheery at the fruit section of his local supermarket, no doubt. The phenomenon is particularly interesting for research in hearing loss, and hearing aid technology as the ability to focus in on certain sounds above others all but dissipates as hearing becomes impaired.

 

Evolutionarily Speaking, Evolutionarily Hearing

The brain prioritizes sounds which are deemed to be more significant to you subjectively. For example, evolutionarily speaking, if during a polite conversation with a new mother in law, your ancestor overheard their name being mentioned by a love rival, followed by “well, he's not my idea of ideal, but I suppose there's always the axe if we need it” - it is no wonder why a brain that prioritizes certain sounds above others would be advantageous. As the attention of the brain drains energy, the subject who uses his brain's resources cleverly and sparingly has better chances of retaining energy and being more attentive to threats or opportunities as they arise over a longer time.

 

Hearing, Speaking... Ignoring

Though there is a commonly held belief that women are more capable of multi-tasking than men, research in this topic suggests that they are just as terrible as each other. Once the attention of a person has been stolen, whether it be by juicy conversation in the background, a possible threat, or even your Facebook newsfeed, the speaker directly in front of you is all but completely drowned out. Only once they utter your name, or trigger your attention by a swift but eloquent drop kicking of your smartphone into the nearest lake, will they have your undivided attention once more.

Vivienne Michael, Chief Executive of Deafness Research UK, has been researching selective hearing with the hope “for improving not just the performance of implants and hearing aids, but the lives of people with hearing disabilities everywhere”. His research has found that the cocktail effect is problematic, particularly for those with one functional ear, and one ear affected by hearing loss. The background of a noisy party, in such cases, cannot be easily dampened out by the brain in favor of focusing in on a certain conversation or sound. The result is an almost dizzying effect wherein the subject is unable to differentiate between sounds, and is instead bombarded with a wall of chatter that cannot be deciphered with ease. Michael believes, as a result, “the auditory system in the brain mix and match sounds from different ears, and then filter out the unwanted noise”. Michael is hopeful that future research will “match the electronic signals of a cochlear (the inner ear) implant with the brain's requirements for listening” in a noisy environment.

 

The Future of Hearing

Companies such as Mimi Hearing Technologies, are dedicated to keeping up with the latest and greatest of research in hearing loss. You can take a test here (LINK) to check how your hearing is holding up, and consider your options as a result. If for example, you've noticed your left hear has started to lose its vigor somewhat, and you're not about to give up on cocktail parties just yet, the answer could be as simple as an ear plug in the weaker ear. Mimi can personalize the external sounds of the world to suit your individual needs. With the advances of smartphones and the digitalization of the hearing aid market, the future of hearing is clearer than ever.

So next time a loved one shushes you in order to eavesdrop on a conversation, don't be too offended. Simply pop in an ear plug, and soak in the gossip. Your eavesdropping ancestors would be proud.

Maria Fabre