Endocrine Abstracts

In order to prove that different sound-waves trigger different human hormones release by the way of their vibratile impact on the bodies, we exposed 30 testers (heterogeneous for gender, age and lifestyle) to different frequencies of noisy sound-waves (not melodic and rhythmic music). We organized three sessions in different days and with different waves frequencies: 1st at 40–115 Hz, 2nd at 8200–8500 Hz, 3rd with mixed radio-waves.

Blood cortisol level was measured with the Access Cortisol Kit (Beckman).

An hour of exposure to a low frequency sound (40–115 Hz) diminishes the hematic cortisol concentration in 86% of the testers. On the other hand, high frequencies (8200–8500 Hz). raise cortisol values in 65% of the testers in just 30-40 min.

After each session, testers expressed their opinion on the experience. Appreciation of low frequencies corresponds to lowered cortisol levels. Dislike of high frequencies corresponds to increased cortisol values, while displeasure of mixed radio-waves (low frequencies) is not associated to higher cortisol levels. This finding suggests that the emotional status does not interfere with cortisol release, as much as the physical properties of sound-waves do.

This pilot study gave several interesting clues, to be confirmed in a larger study: i) high frequencies raise cortisol level, while low frequencies diminish it; ii) this change is not correlated to the emotional response to the exposure; iii) older testers seem to respond in a different way.

Each column refers to one sample collection. The black dots represent each individual cortisol value in Ug/dl. The black bar shows the media of the distribution. The lower limit of the box indicates the middle point between the lowest value and the media while the higher limit indicates the middle point between the higher value and the media.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.