Spatial Sound

The Power of Presence:
How Spatial Sound Affects Our Health

Paul Oomen

P. Oomen


Publication, Research


In conjunction with ‘Spatial Sleep Music’, producer Tom Middleton’s 15-track spatial audio album released in 2022, this article by Paul Oomen unpacks and leverages the neuroscience of spatial audio and its potential for reducing anxiety and inducing calm using psychoacoustic phenomenon of ‘presence’ to guide the listener’s awareness. 

The album was designed to “create a sense of familiarity, comfort and safety before slowly transporting the listeners on an imaginary journey”, with a major focus on helping the listener attain better and deeper sleep.

The article illuminates the scientific background of Tom Middleton’s album, and explores various aspects that were taken as instrumental to the production of the album itself. 

Along with the wave of virtual and augmented reality technologies of the last years, we see the rise of a new horizon in sound experiences: spatial sound technologies are to provide highly vivid appearances of sound that enrich, augment or transform reality as we perceive it. It promises listeners to experience spatial depth and dimensionality of sound in all directions, and from any perspective - sounds coming from above and below, in front and behind, moving away into distant landscapes or coming intimately close to the body.

In the best case, spatial sound technologies allow us to experience sound truly ‘out of the box’: we feel sounds are physically present in space, as if not coming from a defined source such as loudspeakers or headphones. We are encompassed by an acoustic environment in which we can wander and feel present ourselves. Presence refers to the state of someone or something existing, occurring or being in a particular place and also implies the quality of being noticed. In the context of meditation and mindfulness practices, a sense of presence may be understood as a degree of awareness. The more we become aware of our environment, e.g. by means of the presence of sounds around us, the more we become mindfully present within the self. As such, spatial sound is not merely a new attribute to the future of engaging media and entertainment.  There are important implications to the effects such experiences may have on our health and wellbeing.  

A recent study [1] into the effects of spatial sound on human wellbeing shows that spatialized sound has a direct influence on the topology, power amplitude and connectivity patterns of brain waves to an extent that ‘regular’ stereo sound does not. After listening to spatialized sound for no more than 5 minutes, a general decrease in mean power of the Alpha-band, decrease in Alpha: Beta power ratio and decrease in the Low- Frequency (LF): High-Frequency (HF) power ratio of the Heart Rate Variability (HRV) was measured with participants in the study, in conjunction with reduced blood pressure and heart rate. These results are a novelty, as prior to this study it was not known that spatial listening was associated with such changes in the brain activity and vital signs - and that such changes in the human body are not achieved with the more regular ways of audio delivery.

A decrease in Alpha:Beta-wave power ratio may be interpreted as a sign of enhanced relaxation [2] and indicative of enhanced cohesion in brain waves. Lower levels of Alpha-waves at the left-front central cortex are significantly associated with higher levels of self acceptance, environmental mastery, personal growth and total psychological well being [3] and the coupling with positive effects on the cardiovascular and respiratory system [4] in accordance with mood induction. Decrease in Alpha-wave activity is also reported to relate to higher levels of oxygen in the blood [5]. These results indicate participants were in a state of enhanced concentration when exposed to spatial sound, also known as the ‘immersion effect’ [6]. Furthermore, while immersed in a VR experience, Alpha-wave activity has been shown to decrease during arithmetic tasks [7] also suggesting inflicting attention inwards, compared to purely mental tasks. It is generally accepted that the activities of the autonomic nervous system (ANS), which consists of the sympathetic (SNS) and parasympathetic nervous systems (PNS), are reflected in the low- (LF) and high-frequency (HF) bands in Heart Rate Variability (HRV) while the ratio of the powers in those frequency bands, the so-called LF:HF power ratio, have been used to quantify the degree of sympathovagal balance [8].

In short, listening to sounds or music spatially may help us to more effectively process anxiety, stress, improve focus and concentration, and boost the functioning of the nervous system, blood flow and breath.

Another study reveals our psycho-physical response related to room size [9], which is primarily experienced through the reverberation time of sounds. The results suggest that small rooms are considered more pleasant, calmer and safer than large rooms when listening to natural sounds associated with positive presence, such as human and animal sounds. The smaller room size reached higher levels of valence and lower levels of arousal, and significantly higher values of safety confirmed by physiological markers.

The same study also shows that sounds heard behind the listeners tend to be more arousing and elicit larger physiological changes than sources in front of the listeners. It is known that we show greater tendency to locate sound sources at our back when no visual cues are available [10]. This may be attributed to a sensory bias of the hearing modality towards the space outside one’s visual field thus causing a higher effectivity of reaction. It is suggested that the auditory and visual systems complement each other in such cases. Listening is in charge of detecting possible threats and alarming [11] in order to then shift visual attention focus to obtain more detailed spatial information. This interaction of perceptual and affective systems may help to sustain a constant margin of safety around our body as described in theories on embodied emotions [12].

As such, there is a wealth of potential application of spatial sound technologies in various forms of music therapy, sound treatment and mood-inducing devices. When using a considerate approach to acoustic simulation of room size and directionality of sound sources, it could stimulate particular physiological and psychological responses in the listeners.

The reason why beneficial applications using spatial sound are not yet as widespread as one might expect based on these results, is because the quality demands to provide a full spatial sound experience still pose serious challenges to today’s consumer standards of available sound technologies.

Experiments before the 1960-ies [13] already showed that if the dimensions of the reproduced sound sources exceeds those of the loudspeaker box, listeners experience a message-media conflict. Listeners are not able to accurately correlate the shape, size and distance of the projected sound source because the loudspeaker is ‘in the way’. The transparency and coherence of the spatial experience is occluded by the features of the loudspeaker itself. Audio stimuli played back by high-fidelity loudspeakers have been observed to better enhance relaxation and decreasing Alpha-wave power [14] compared to lower-fidelity audio stimuli. In other words, if the fidelity of our loudspeaker system is not up to standard, we may not be able to get the full benefits of spatial sound.

This study [15] shows that compression formats, such as the widespread .mp3, negate the experience of presence of the sound source and generate negative emotional responses to the reproduced sound, such as increased eeriness and anxiety. We may conclude that the audio streaming formats dominating our media landscape at present are not fit to accurately deliver the benefits of spatial sound.

And if we expect a fully out-of-the-box spatial experience through our headphones or earbuds, we may be disappointed. Current standards providing spatial sound for headphones, for instance, suffer to a significant extent from the fact that every person’s auricles of both left and right ears are uniquely shaped and in turn there are uniquely individual ways how we perceive and parse spatial cues in a sound signal [16]. Such spatial cues are further informed by the involuntary rotating and tilting of the head for better sound orientation [17]. Headphones obstruct us to do this effectively - when we turn and twist our head, the headphones turn with it.

Listening is understood to be an act of the entire body [18] and the acoustic experience of the body is not catered well by headphones alone. A better balance is achieved when the address of sound for the ears through air-conduction is paired with vibro-acoustic stimulation of the body through bone-conduction. For instance, vibratory stimulation of the vagus nerve may increase one's sense of spatial depth and warmth of sound. The audible sounds are supported by inaudible vibrations in the infrasonic spectrum that can be felt resonating in the cavity of the chest and traveling through the spine, creating a whole body experience. Interestingly, it has also been shown that stimulating the vagus nerve effectively activates the PNS [19], aiding digestion, reducing blood pressure, regulating the immune system, stimulating hormonal response and improving general psychological well-being. To increase our sense of presence of sound in space, we may have to prepare for dressing in haptic wearables that will extend stimuli throughout our bodies.

Furthermore, multisensory research suggests that seeing a room effectively influences how people perceive the room through their ears [20], and that vision dominates when the two modalities are unmatched. As such, the environment you are in will make or break your spatial sound experience.

It seems that to upgrade spatial sound experiences, we will need to have uniquely adapted filter algorithms designed based on measurement of our own ears, wear head-tracking sensors on our head, dress in full-body haptic suits and require a real-life (or virtual) environment that matches the soundscape we are listening to. This seems a lot to ask. Above all, this makes clear the need for new, smarter and more integrated technologies that resolve these limitations in more elegant ways and can set a new standard for the integration of spatial sound in consumer technologies.

Despite recent advances in popularizing spatial sound technologies and making them more widely available, it is still early days for the integration of spatial sound as a medium. New breakthroughs in delivery through mass-available technologies will be required to make these levels of experience accessible outside of the highly-specialized spatial sound studios and laboratories of the world. Research that investigates the effects of spatialized sound on health and wellbeing is still in a nascent state and many questions are at present left unanswered. For example, we still have no precise understanding of the psychological effects of the directionality of sounds in the free field, or how to match the shape and dimensions of sound sources to particular changes in the physiology of the human body, just to name a few. However, the promise of a range of beneficial effects that spatial sound technologies could provide to improve our mental and physical health is the best possible reason to foster further research and increase the development of user-ready applications.

In a world where our attention is constantly drifting between the physical and the digital, the technologies integrated in our lives transport us ever further and faster into the realms of the virtual, causing increased loneliness and depression [21]) as well as detachment and anxiety [22] as major threats to societal health. Spatial sound shows potential to counterbalance these developments. In its physical immediacy, it brings us back to an awareness of presence in the here and now. Spatial sound presents us with ‘void’, a visceral experience of limitless time and borderless space that allows curiosity and imagination to emerge. Among the multiplicity and fragmentation of our digitally connected lives, it challenges us to listen to the world in a more engaging way, emphasizing patience and reticence in contrast to the driving forces of our everyday existence - speed, efficiency and immediate gratification. As such it holds a great promise for future sound applications with an impact far beyond the mere supporting role of sound in present-day entertainment-driven applications.

Paul Oomen, March 2022 ©

About the Author: Paul Oomen is the Founder of spatial sound studio 4DSOUND and Founder and at present Head of Curation of the Spatial Sound Institute, Budapest Hungary. He is also co-Founder and at present Head of Research and Development of The Works Research Institute where he conducts scientific study into the effects of sound on human wellbeing, natural environment and consciousness.

The realization of this article has been supported by Sensate.
[1] R. Geffen, C. Braun, The Effect of Geometric Sound on Physical Matter, Brain Waves and Well Being and its Application for Advanced Medicine, Jan 2021.

[2] R. F. Navea et al, Conference paper -Project Einstein 2015, At De La Salle University - Manila,

[3] H. L. Urryet et al, Psychol Sci;15(6):367-72 Jun 2004.

[4] M. Grohn et al, Proceedings of the 18th International Conference on Auditory Display, Atlanta, GA, USA, June 18-21, 2012.

[5] H. Yuan et al, Neuroimage. 1; 49(3): 2596, Feb 2010.

[6] S. Lim et al, Sensors (Basel) 8;19(7):1669, Apr 2019.

[7] E. Magosso et al, Computational Intelligence and Neuroscience Volume 2019.

[8] S. Park et al; Int J Environ Res Public Health; 14(9): 1087, Sep 2017.

[9] A. Tajadura-Jiménez et al; When Room Size Matters: Acoustic Influences on Emotional Responses to Sounds, Emotion 10(3):416-22,  June 2010.

[10] A. Tajadura-Jiménez, A. Väljamäe, N. Kitagawa, & H. Ho, Whole-body vibration influences sound localization in the median plane. In Proceedings of the 10th Annual International Workshop on Presence, Barcelona, Spain, 2007.

[11] P. N. Juslin, D. Västfjäll, Emotional responses to music: the need to consider underlying mechanisms. Behavioral & Brain Sciences, 31 (5), 559-575; discussion 575-621, 2008.

[12] P. M. Niedenthal, P. M. Embodying emotion. Science, 316(5827), 1002-1005, 2007.

[13] G. Von Bekesy, Experiments in Hearing, 1960.

[14] T. Harada et al, International Medical Journal (1994) 23 (no.1):1-3 · April 2016

[15] R. Mo et al, Journal of the Audio Engineering Society PAPERS Vol. 64, No. 11, Nov 2016.

[16] S. Mehrgardt, S. Mellert, ‘‘Transformation characteristics of the external human ear,’’ J. Acoust. Soc. Am. 61, 1567–1576, V.1977.

[17] F. L. Wightman, & D.J. Kistler, Resolution of front-back ambiguity in spatial hearing by listener and source movement. The Journal of the Acoustical Society of America, 105(5), 2841‑2853, 1999.

[18] C. Wu et al, Listening to another sense: somatosensory integration in the auditory system, Cell Tissue Res.;361(1):233-50. Jul 2015.

[19] from web:

[20] P. Larsson, D. Västfjäll, P. Olsson & M. Kleiner, When what you see is what you hear: Auditory-visual integration and presence in virtual environments. In Proceedings of the 10th Annual International Workshop on Presence, Barcelona, Spain, 2007.

[21] M. G. Hunt, R. Marx, C. Lipson & J. Young, No More FOMO: Limiting Social Media Decreases Loneliness and Depression, Journal of Social and Clinical Psychology, Vol. 37, No. 10, pp. 751-768, 2018.

[22] K. F. Pfaffinger, J. A. M. Reif, E. Spieß & R. Berger, Anxiety in a Digitalised Work Environment, Gr Interakt Org 51:25–35, 2020.