Theta, alpha and beta binaural beats all lowered blood pressure, and equally

If different beat frequencies do different things to the brain, they should do different things to the body. Yang and colleagues tested that in 65 students, each of whom listened to twenty minutes of nature sounds carrying binaural beats at 6 Hz (theta), 10 Hz (alpha) and 25 Hz (beta), with blood pressure and heart-rate variability measured before and after each session.

All three frequencies were followed by lower readings: heart rate and both blood pressure numbers after theta, systolic pressure after alpha, and heart rate, systolic pressure and a shift in heart-rate variability toward the parasympathetic side after beta. When the three were compared with each other, there was no difference.

The authors summarise this as binaural beats reducing anxiety regardless of frequency. The absence of any difference between frequencies is the more informative result, and it points the other way: twenty minutes of sitting with nature sounds in headphones is calming, and the beat frequency may not be doing the work.

Limitations. No control condition without beats, so the effect of simply resting with pleasant audio cannot be separated from the beats. Unblinded, single sessions, and physiological measures that respond to rest alone. We grade it weak.