Can we really use sine waves to hack our brains?
Not to be confused with the technique of binaural recording, binaural beats are created when two tones with slightly different frequencies are played separately in each ear via headphones, causing our brain to perceive an additional ‘pulsing’ effect. Many have claimed that listening to sequences with binaural beats can reduce stress and anxiety as well as increase one’s concentration and creativity. Does this phenomenon promise real benefits, or are binaural beats nothing more than an auditory illusion?
How to make binaural beats
For all these impressive claims, actually creating binaural beats is incredibly straightforward. In acoustics, beats occur when two tones with slightly different frequencies interfere with one another and vary in volume based on the difference between those two frequencies. When you take two similar tones with frequencies below 1.5 kHz and present them independently to each ear, your brain will begin perceiving a third pulsating tone that represents the difference between each sine wave. That’s the beat in binaural beat, and it’s actually an auditory illusion. In the recording below, I took two sine waves (one at 500 Hz and one at 495 Hz) and panned them hard left and hard right. Throw on a pair of headphones and see if you can hear that third tone, which represents a 5 Hz difference between the two waves.
When I first heard about binaural beats, they were being promoted as a way to get high by the alternative medicine community. Sites like I-Doser began monetizing the experience with a proprietary app that could play back purchased audio content. Their ‘doses’ are meant for a variety of purposes, including simulating the effect of various controlled substances. Despite how skeptical you may be feeling right now (the feeling is mutual), I-Doser rode that initial wave of online interest and racked up millions of app downloads in the process.
Other companies have since followed suit by claiming that binaural beats can help ‘hack’ one’s brain through neural entrainment, in which the brain actually matches its own electrical signals to one’s rhythmic perception of sound. We already know that certain brainwave patterns are associated with aspects of human sleep, dreaming, conversation, active thought, and meditation. However, claiming that binaural beats will transform you into some sort of AirPod-wearing superhuman with heightened intelligence and zero headaches is a huge stretch without solid evidence.
So, do binaural beats really work?
From a research standpoint, the quality of studies as well as their results have historically been mixed. A 2016 study found that listening to binaural beats at higher frequency ratios led to slight improvements with memory-related tasks, while other variables actually led to a decrease in accuracy. On the other hand, a 2017 study involving EEG measurement of electrical brain activity didn’t find any solid evidence that binaural beats at various brainwave intervals had an effect on human brain activity or basic emotional states.
However, a recent review of multiple other studies did identify some correlations between binaural beat therapy and decreased levels of anxiety and pain perception, so it may still be a bit early to put this one in the pseudoscience corner. Just as with the concept itself, perception plays a big role. If someone feels like these recordings truly help them meditate better, concentrate more, or reduce restlessness, then I believe that’s worth something. Binaural beats may not take you on some crazy trip but they’re still worth a listen, especially when you can make your own!
February 12, 2020