International Congress of Endocrinology/
European Congress of Endocrinology
media release
Embargoed until 00:01 CEST, Monday 7 May 2012
The sound of stress
High-pitched sound raises the stress hormone cortisol while low-pitched sound reduces it
according to a small pilot study presented at the joint International Congress of Endocrinology
and European Congress of Endocrinology in Florence, Italy.
An Italian research team found that 86% of its test subjects had decreased cortisol levels after
an hour listening to a low-frequency sound. 65% of the same testers experienced an increase
in cortisol after exposure to a high-frequency sound for a similar length of time.
The researchers focused on simple sound waves – not music, as many previous studies have
done – adding evidence to their theory that it’s the physical properties of sound, not the
appreciation of melody, that cause a physiological response in humans.
The human ear is capable of hearing frequencies ranging between approximately 20 hertz (the
lowest note on a large pipe organ) to 20,000 hertz (a high shrill dog whistle). Low frequencies
(a bass drum, thunder, a deep man’s voice) and high frequencies (a squeak, squeal, or high
woman’s voice) are registered at different locations inside the cochlea, the auditory portion of
the inner ear.
This study exposed 30 healthy testers (mixed gender, age, and lifestyle) to different sound
frequencies modulated with a sequencer. Three evening sessions were spaced out by threeday intervals: the first session tested low-frequency sound waves (40 to 115 hertz) and the
second session looked at high-frequency sound waves (8200 to 8500 hertz). The third control
session used radio music adapted from three FM channels (mixed low-frequency sound
waves).
The testers refrained from eating, drinking alcohol or caffeine, smoking and physical exercise in
the eight hours prior to each session. After 30 minutes of relaxation, an initial blood sample was
taken at 20:00. Sound was then played at a high volume of 1000 watts. Blood samples were
taken again after 40 to 60 minutes while the sound continued to play. The high-frequency group
was allowed five minutes of silence in between two twenty minute sessions. They were also
given ear plugs to prevent inner ear damage. At the end of each session participants filled out a
questionnaire designed to analyse their emotional reaction to the experience.
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The results confirmed that exposure to sound waves can change blood cortisol levels in both
directions depending on the frequency used. In the first and third low-frequency groups there
was a reduction in cortisol levels (evidenced in 86% and 72% of testers, respectively). Cortisol
dropped an average of 26% from the base reading in the first session and 18% in the third
session.
In the second high-frequency group 65% of testers experienced an increase in
cortisol levels, which rose an average of 37%. Although the participants ranked both the
second and third sessions as unpleasant, only the second session saw an increase in cortisol
levels, suggesting that the sound wave was responsible for the cortisol shift and not the
participant’s emotional status.
Cortisol is an important hormone which regulates a wide range of processes throughout the
body including metabolism, immune function, and blood pressure. It also plays a crucial role in
helping the body react to stress and has been dubbed the “stress hormone” because it is
secreted in higher levels during the body’s “fight or flight” response. Blood levels of cortisol vary
but are generally high in the morning and fall throughout the day. Small increases in cortisol
can help the body effectively respond to stress, but raised cortisol levels in the long term can
cause wide-ranging health problems.
The results of this research pave the way for a larger study to confirm the findings as well as
explore the medical benefits of sound waves. Further analysis will also look more closely at
statistical differences related to age and sex.
Researcher Dr Chiara Olcese said:
“Searching for links between neuroscience, endocrinology and music is not only interesting and
curious – it may also be useful for medical treatment in the future. Our study shows that the
frequency of sound can potentially affect a person’s cortisol levels, with higher frequencies
raising production of this hormone. We now need to carry out further work to examine in more
detail the medical implications of this work. I hope that people will become more aware of the
power of sound and the unseen effects that it can have on the body.”
----------Ends---------Notes for editors
The poster (P56) will be presented at the International Congress of Endocrinology/European Congress of
Endocrinology at 17:55-19:30 on Monday 7 May 2012.
th
th
The joint 15 International Congress of Endocrinology/14 European Congress of Endocrinology,
Europe’s biggest scientific meeting on hormones, is taking place in Florence, Italy on 5-9 May 2012. For
the full programme, see http://www.ice-ece2012.com/.
Please mention the International Congress of Endocrinology/European Congress
of Endocrinology in any story
For more information: please contact the European Society of Endocrinology press office
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Toby Stead
+44 (0) 7557 193 345
[email protected]
Tom Parkhill
+44 (0) 7924 815 389
[email protected]
Jennie Evans
+44(0)7773 797 501
[email protected]
The European Society of Endocrinology aims to promote research, education and clinical practice in
endocrinology for the public benefit. http://www.ese-hormones.org
The International Society of Endocrinology aims to become the premier international organisation for
endocrinologists and associated scientific professionals, advancing the profession and improving the
efficiency and effectiveness of endocrinology information exchange at international level.
http://www.endosociety.com/
ABSTRACT
Soundwaves’ effect on hematic cortisol level: a pilot study
C. Olcese
1
1,2,3
3
2
1
, A Fiorin. Damiani , R. Dittadi , P. Borasio & L. Bartoloni
2
2,1
3
University of Ferrara, Ferrara, Italy; ULSS 12, Venezia, Italy; DENSO, Vittorio Veneto, Italy.
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
minutes. 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: 1) high frequencies raise
cortisol level, while low frequencies diminish it; 2) this change is not correlated to the emotional response
to the exposure; 3) older testers seem to respond in a different way.
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