If you've ever scrolled through digital platforms for "study music" or "deep sleep frequencies," you've likely come across binaural beats. These tracks claim to do everything from boosting your cognitive performance to curing insomnia by "entraining" your brainwaves. But does the science actually back up these bold claims?
A comprehensive systematic review published in PLOS ONE took a critical look at the scientific literature to see if binaural beats really can change your brain activity.
What Exactly Is a Binaural Beat?
A binaural beat is actually an auditory illusion. It happens when you hear two slightly different frequencies in each ear—usually requiring headphones to deliver separate isolated audio streams to each side.
For example, if a tone of 400 Hz is played in your right ear and a tone of 420 Hz is played in your left ear, your brain doesn't just hear two separate sounds. Instead, the central auditory pathways process the phase difference between them and create a perceptual illusion of a third, phantom tone—a beat oscillating rhythmically at the difference frequency of 20 Hz.
The Big Idea: Brainwave Entrainment
The therapeutic magic is supposed to happen through a mechanism called the Brainwave Entrainment Hypothesis. The theory suggests that if you expose the auditory system to a specific frequency (like a steady 7 Hz beat), the electrical macro-activity of the brain's neural networks will eventually synchronize and ripple at that same 7 Hz frequency.
Should You Still Listen?
Even if the strict neuro-entrainment mechanism isn't fully proven yet, binaural beats remain a very safe, low-risk, and accessible tool. Pro Tip: Use stereo headphones.