SONOR

The science · Brain waves

Theta, explained

Theta covers about 4 to 8 Hz. Clinical EEG guidelines describe a frontal theta rhythm that appears during mental tasks such as problem solving. Here is what researchers have measured with theta-rate sound, and what Sonor does with the band.

What the research says

The clinical EEG glossary defines theta as 4 to under 8 Hz and describes a fronto-central theta rhythm during cognitive tasks (Kane et al. 2017). Researchers study frontal midline theta during memory tasks, though a 2014 review says its functional significance in human memory "remains largely unknown" (Hsieh and Ranganath 2014).

Theta was the most studied band in a 2023 systematic review of 14 EEG studies: 10 used theta-range binaural beats. Three reported theta power increasing, one only for relative power, and seven reported no theta change attributable to the beat (Ingendoh et al. 2023).

In a 2017 study, 28 participants heard a 6 Hz binaural beat for 30 minutes. Theta activity rose within 10 minutes compared with a control group (Jirakittayakorn and Wongsawat 2017). In a 2012 study of 31 people, 2 minutes of 7 Hz or 16 Hz binaural beats produced no difference in vigilance or cortical power compared with white noise (Goodin et al. 2012).

A 2026 meta-analysis of theta binaural beats found 13 randomized trials (630 participants). Only pain could be pooled: 4 trials, 173 participants, a standardized mean difference of -0.53 (95% CI -0.84 to -0.23), which the authors rated low certainty (Fatima et al. 2026). This is not a claim about Sonor.

Sonor has a preset at 7.86 Hz named after the Schumann resonance. No peer-reviewed study was found that tested sound pulsed at that rate as its own condition.

Overall, the evidence is weak and mixed, with more null than supportive EEG studies. We make no claim about what theta tones do for you.

How Sonor uses it

Sonor's theta range pulses the tone from 4 up to, but not including, 8 times a second. The picker offers 4, 5.5 and 7.86 Hz. The pulse plays continuously, quietly under music or ambient sound. It is not timed to your own brain waves.

This isn't medical advice. Pulsing audio can affect people with epilepsy or a seizure disorder, so check with a doctor before using it if that applies to you.

Related