It happens to all of us from time to time—you’re in a conversation, someone says something, and you instinctively reply, “What?” before your brain catches up and you realise you actually did hear them. You might laugh it off or brush it aside, but when this happens often, it could be telling you something important about how your brain and hearing are working together.
Let’s explore why this common habit happens, what’s really going on behind the scenes, and how you can tell if it’s more than just a slip of attention.
Your Brain Processes Sound in Layers
Hearing isn’t just about your ears—it’s about your brain. When someone speaks, your ears pick up sound waves, but it’s your brain that decodes those vibrations into words and meaning. This process happens incredibly fast, but sometimes the brain gets a little behind.
If you’ve been multitasking, daydreaming, or focusing on something else, your auditory processing can lag for just a moment. That’s when you blurt out “What?”—because your brain hasn’t fully registered what was said yet. Within a second or two, the meaning clicks, and you realise you actually did hear them after all.
This brief delay is part of what’s known as cognitive load. When your mental “bandwidth” is full—whether from work stress, background noise, or even fatigue—your brain has less capacity to process language immediately. It’s not that your hearing has failed, it’s that your attention has.
When It’s More Than Just Distraction
But here’s the tricky part: sometimes frequent “Whats?” aren’t about distraction at all—they’re early signs of hearing changes that you might not notice right away. You may still hear sounds, but certain frequencies—especially high-pitched ones like consonants—start to fade.
If this happens, your brain struggles to fill in the blanks, particularly in environments with background noise like cafés or busy offices. The result? You catch the rhythm of speech but miss key details, prompting that automatic “What?” as your brain scrambles to fill gaps.
For people noticing this pattern regularly, it’s worth considering a simple check-up like hearing tests Marrickville or with a qualified local audiologist. Many are surprised to learn that gradual hearing loss can develop subtly over years, making it easy to mistake for simple inattention.
Background Noise Makes It Worse
Modern life is loud. Whether it’s traffic, appliances, music, or chatter in open-plan spaces, background noise puts extra strain on your brain’s auditory processing system. Even people with perfectly normal hearing can struggle to separate speech from noise.
This is called the cocktail party effect—the brain’s ability to focus on one voice among many. It’s impressive, but it takes effort. If you’ve had a long day, are tired, or under stress, your brain’s ability to filter sound declines. That’s why noisy environments often make you say “What?” even if your hearing is fine.
To minimise this, try turning down background noise when having conversations, or face the person you’re speaking with so you can pick up visual cues. Eye contact and lip movements give your brain extra context, helping it process speech more efficiently.
Listening Fatigue Is Real
If you find yourself exhausted after long conversations, meetings, or social events, it might be listening fatigue. This happens when your brain works overtime to decode unclear or partially heard speech.
Just like your muscles tire from physical effort, your brain tires from continuous auditory strain. You may start zoning out or asking people to repeat themselves more often—not because you’re not paying attention, but because your mental energy for decoding sound has run out.
Taking short breaks, moving to quieter areas, or reducing overlapping noise can help. If you experience this regularly, it might also be a sign to get your hearing checked.
The Role of Selective Attention
Have you ever noticed how you can tune out one sound but suddenly snap back when someone says your name? That’s selective attention in action. Your brain prioritises sounds it considers important and filters out the rest.
However, if you’re under chronic stress, not sleeping well, or constantly multitasking, your selective attention can weaken. That’s why you may find yourself saying “What?” more often, even in quiet settings.
It’s not that you didn’t hear—it’s that your brain didn’t tag the sound as “important” quickly enough. Training yourself to slow down and give full attention to conversations, especially in noisy environments, can reduce this effect over time.
Technology and Cognitive Overload
Between constant notifications, streaming, and background screens, your brain rarely gets a break. Modern technology constantly demands your attention, and multitasking between auditory and visual inputs creates cognitive overload.
When you’re watching TV, scrolling on your phone, or listening to music while talking to someone, your brain’s processing power gets divided. It can cause temporary “deafness” to speech, leading to that habitual “What?” before your brain switches focus back.
Try reducing multitasking when communicating. Turning off background screens or pausing what you’re doing can make your interactions smoother and more mindful.
Hearing Loss Isn’t Always Obvious
Mild hearing loss often develops so gradually that people adapt without realising it. You might unconsciously start reading lips more, increasing TV volume, or avoiding noisy environments. You might even think others are mumbling.
That constant “What?” can be your brain’s way of alerting you to subtle hearing decline. It’s especially common for adults over 40, as natural age-related changes begin to affect the delicate hair cells inside the inner ear.
Early detection is key. Addressing mild hearing loss early—through hearing aids, training, or environmental adjustments—can prevent the brain from “forgetting” how to process certain frequencies. Left unchecked, untreated hearing loss can lead to social withdrawal, fatigue, and even memory issues over time.
The Emotional Side of Mishearing
Hearing isn’t just physical—it’s social and emotional. Repeatedly asking people to repeat themselves can be frustrating or embarrassing. Some people start pretending they heard everything to avoid seeming inattentive, which can lead to misunderstandings or isolation.
This creates what psychologists call communication anxiety. When people worry about missing parts of conversations, they often withdraw or stop participating as actively. Ironically, this avoidance reinforces the problem, because social interaction is one of the best ways to keep your auditory and cognitive systems sharp.
Acknowledging the issue—rather than ignoring it—is empowering. Understanding that it’s a common experience shared by many helps remove the stigma and encourages you to take practical steps.
What You Can Do About It
If you’ve noticed yourself saying “What?” more often, there are a few simple things you can do right away:
- Reduce distractions: Give conversations your full attention whenever possible.
- Manage noise: Turn off TVs, lower background music, or move to quieter spaces.
- Face the speaker: Body language and lip movements improve comprehension.
- Rest your ears: Take quiet breaks throughout the day to reset your hearing focus.
- Monitor changes: If you notice this happening more frequently, schedule a hearing check.
Modern hearing assessments are quick, painless, and often free or low-cost. Even if your hearing is perfectly normal, you’ll walk away with a clearer understanding of how your auditory system works—and some peace of mind.
A Little Awareness Goes a Long Way
Saying “What?” now and then is normal—it’s part of how our brains juggle focus, sound, and conversation. But if it’s happening all the time, your body may be signalling that it needs a bit of attention. Whether it’s stress, noise fatigue, or early hearing changes, small adjustments can make a big difference.
By understanding what’s really behind that automatic response, you can catch issues early, improve your communication, and enjoy richer, more effortless conversations every day.