The 4 ways sound affects us

I want to talk in this short blog about the ways sound affects us. You can listen to the blog or read the transcript below.

My new book, How to be Heard, is all about communicating, and it’s also about sound.

Sound has four very powerful effects. The sound of your voice will do this just as much as anything else. In fact, probably more than anything else. I’m fond of saying that the human voice is one of the most powerful sounds on the planet. It’s the only sound that can say I love you or even start a war.

So let’s think about the four ways in which sound affects us.


The first is physiologically. Sound affects our bodies. Your body is 70% water. Sound travels well in water, so we’re very good conductors of sound. It’s not surprising that sound has a powerful effect on us. Hearing is your primary warning sense, just like every animal on the planet. Do you know there are no deaf vertebrates? There are plenty of vertebrates who don’t see very well at all or not at all, but the hearing is a universal sense, as Seth Horowitz calls it. Incidentally I interview Seth in How to be Heard, and there’s an audio version of that which is available on the website too for those who bought the book.

Now, sound affects us physiologically in very powerful ways. Because hearing is your primary warning sense, a sudden sound will start a process. It releases cortisol, it increases your heart rate, it changes your breathing. This is because we’ve been programmed over hundreds of thousands of years to assume that any sudden or unexplained sound is a threat and your body gets ready to fight or flee. That happens to us an awful lot. Even though we may know that a bus letting off its air brakes or a car backfiring or somebody dropping a plate is not dangerous, it nevertheless puts us into that state. By the way, if you’ve got an alarm clock with a traditional bell, or even a beeper on it, a buzzer, any kind of sudden sound, please change it. It’s not good for you to wake up to that kind of sound.


The second way sound affects us is psychologically. It changes our emotions and our moods. Music will do that, of course. I’m sure you can think of a song that will make you happy. Maybe you’re thinking of it right now as I speak. I’m thinking of one of my favourite songs, which is Riverman by Nick Drake. It always makes me feel calm and happy.

So music changes our mood. However, it’s not the only sound that does that. There are plenty of sounds in nature that do. Bird song for example makes us feel relaxed and reassured, because we’ve learned over hundreds of thousands of years again that when the birds are singing we’re normally pretty safe. Sound can affect our emotional state quite deeply.


Thirdly sound affects us cognitively. How well you work is very dependent on the sound around you. Your kids may tell you that they do their homework much better with loud music playing. It’s not true unfortunately. The loud music is probably taking up critical audio bandwidth and they’re not able to hear that internal voice so well. They may do their homework for longer so you may get a better result, but they’re not doing more work per minute. The most distracting sound of all is the human voice. If somebody’s speaking next to you, it’s very difficult to block out that sound. We have no earlids and distracting human conversation hugely impedes your productivity.


The final way sound affects us is behaviourally. We will tend to move away from unpleasant sound if we can and even gravitate towards pleasant sounds. Sound can cause stress us and make us behave negatively. It makes us less sociable, less helpful and less approachable if we’re in a noisy setting.

So sound changes us in four powerful ways and those four ways are running all the time. It’s important to know this because if you start to listen consciously to the sound around you, you could start to design your environment so that those effects are not working against you.