Linguistic overview/critique of the Tomatis method

Question

Some advertisements for language training material (like this and this) have a dubious claim that each language has its own frequency range of sounds, or a "pass band", so that listening to sound, including music, tuned to that range (don't ask me how) and getting your brain used to the range beforehand will improve your acquisition of the language.

The claim seems to originate from the work French ENT doctor Alfred Tomatis published in the 1950s, and apparently it's originally applied to treatment of children with disabilities rather than language learning.

As far as I can tell this is pseudoscience, or at best protoscience, but all I've been able to find are some papers, typically in developmental psychology, saying they failed to replicate the claimed benefits (e.g. Kershner et al. 1990). This website boasts a list of studies that purportedly demonstrate the effect of the method, some of which are from well-known academic publishers. I wonder if they do in fact demonstrate it and how representative they are of the literature available (and if they meet the ethical standards on conflicts of interest).

Is there an outline or review of the method from a linguistic point of view? Like one that I can point to in order to deter someone from falling for it.

Answer 1

An [a] is an [a] is an [a] is an [a]. It doesn't matter what language it's from, it will always be an [a], and feature the same formants, and therefore the same frequencies

It is true that different languages do use different phonetic inventories, and some phonemes do have formants with more extreme frequencies, but phones with very high frequency formants (e.g. [s]) and phones with very low frequency formants (e.g. [m]) are as close to universal as anything gets

So the range of frequencies two random languages use are likely pretty similar, but they will definitely have a different distribution within that range, and the combinations those frequencies occur in will also vary

It's possible that listening to audio with a similar distribution and combination rules will train your brain to listen for the pertinent distinctions, but this is a very different claim from different languages having different "pass bands" of frequencies they use and, of course, the easiest way to get audio with the appropriate properties is simply to listen to audio in the language, something that is well demonstrated to aid in acquisition of the language