Auditory-tactile synesthesia

Alternative names sometimes used are sound-touch and audio-tactile

With this type of synesthesia, certain sounds trigger actual physical sensations in different parts of the body. They can be felt within the body or on the skin, or they can be related to proprioception (awareness of the nature, position and movement of the body).

Some manifestations that have been described are pressure on the skin; a sensation of tickling or puffs of air; pinpricks; pulsations; muscular contractions; pins and needles (paresthesia); strong sensations in hands or feet or under nails; localised pressure inside the body; oppression on the chest; electric zapping sensations travelling through specific body parts (but not unpleasant); waves of pleasure affecting all or part of the body; repetitive twitching or other uncontrollable movements; sensation of a geometric shape in your hands or against the skin or moving around the body; the physical sensation of touching a texture; the impression that the body is moving in a particular direction or rising or floating; sensation of metamorphosis of part of the body; cataplexy (sudden drowsiness and loss of muscle tone while the mind remains lucid).

These tactile concurrents tend to be pleasant or neutral rather than troublesome or painful, although these latter reactions are sometimes possible. Auditory-tactile synesthesia appears to have an emotional component and it might be connected in some way to emotions triggered by the music, although studies are needed to determine whether this is so. In any case, the tactile sensations are highly specific, they are consistent and idiosyncratic (unique to each synesthete) and they are different from phenomena such as frisson or ASMR that affect many people, synesthetes and non-synesthetes alike, and which are not considered a type of synesthesia (see below for more information on these two phenomena and others). 

It is believed to be a relatively uncommon type of synesthesia (according to Sean Day's study of prevalence, only 5% of synesthetes have this type) although the percentage might actually be higher as it is a type on which there has been little research compared with others. Practically all the specific studies conducted on auditory-tactile synesthesia have focused on the type that occasionally arises in cases of brain injury (adventitious synesthesia), rather than the natural type we talk about on this website.

Some characteristics of auditory-tactile synesthesia:

It is consistent. Basically, the same sound heard under the same circumstances tends to evoke the same synesthetic tactile reaction (although there is little research on this subject).  

The degree of focus and relaxation is important: the tactile response tends to be strong and well-defined when the synesthete is relaxed and concentrating on the sound or music, and weaker or non-existent if they are concentrating on something else. Also, the experiences can be milder or not occur at all if the person is feeling tense and nervous but tremendously strong in a case of very deep relaxation, similar to a state of advanced meditation.

The quality of the sound also has an impact: both visual and tactile synesthesia tend to respond more strongly with good sound quality, listened to through good headphones, while a weaker response is caused by music that is distant or less surrounding.

The tactile effect can be cumulative: with certain types of music it can sometimes only start after many seconds or a few minutes, increasing in intensity as the same sounds repeat.

It can sometimes be accompanied by a perception of colour, i.e. that the tactile feeling created by the sound is of a particular colour.

It often coexists with auditory-visual synesthesia, giving rise to tactile and visual sensations at the same time.

What kind of sounds evoke auditory-tactile synesthesia?

It can be triggered by both musical and non-musical sounds, and it varies from person to person. In many cases the sound of each musical instrument is felt in a different part of the body or has its own specific tactile sensation, which is always consistent, so the inducer in this case is timbre. Alternatively, it may be specific to each song or musical genre. Although apparently much less common, auditory-tactile synesthesia can also be prompted by the different musical pitches (frequencies), keys or chords. There are also people for whom voices are the principal trigger. Electronic sounds (and electronic music) can create tactile concurrents in many cases, and an example that tends to have a strong effect is autotune used to synthesise voices. Depending on the particular synesthete, other factors that can have a bearing are the degree of harmonisation, the tempo (and speed changes), the volume (intensity), and there can perhaps be a relationship with the emotion caused by a particular sound or musical sequence. These last two examples should not be confused with feeling vibrations from the music in your body or with frisson, which are not synesthesia (for frisson, see below).

Types of synesthesia related to auditory-tactile 

Mirror speech synesthesia

Mirror speech is a type of synesthesia that has been very little studied and appears to be very uncommon (according to Sean Day’s study only 0.18% of synesthetes have this type), but it could be considered a manifestation of, or at least related to, auditory-tactile synesthesia. When someone with this type hears another person speak they get the feeling that their own mouth, throat and even stomach are moving as if they were producing the same sounds. This type also has a certain similarity with mirror touch synesthesia.
Auditory-motor synesthesia

Some people with auditory-tactile synesthesia also experience another uncommon phenomenon, auditory-motor synesthesia, which consists of involuntary body movements triggered by sound.

Go to the page on auditory-motor synesthesia

Sound-texture synesthesia

For people with this type, hearing different sounds produces a perception of textures. However, in practice the textures usually accompany another concurrent of their synesthesia – normally colour, shape, taste or touch sensations – rather than being evoked individually, so sound-texture might not actually not be a type of synesthesia per se. In any case it is different from auditory-tactile synesthesia as it does not involve real physical tactile sensations on the body. It can coexist with auditory-visual synesthesia for example, creating visualisations of textured colours, or shapes with both colour and texture, but in this case the textures are not felt physically on the hands or on other parts of the body, and it is these real physical touch sensations that are the hallmark of auditory-tactile synesthesia.

Go to the page on sound-texture synesthesia

Auditory-tactile and sound-texture: projection and association?

Auditory-tactile and sound-texture synesthesia have been compared to projective and associative synesthesia respectively, auditory-tactile being the equivalent to a projected visual synesthesia as it is actually felt physically and not just in the mind. This is a very valid interpretation, although the terms “projective” and “associative” are currently only used for visual synesthesias and not for those with concurrents in the other senses.

Cross-modal correspondences: something everyone can do

Up to a point, all of us are able to associate textures with sounds. These associations are called “cross-modal correspondences” (or "cross-modal associations”) because they involve two different sensory modes, but they are not considered synesthesia as they do not occur consciously. The differences are as follows:

A person with sound-texture synesthesia: whenever they hear a particular sound they perceive a texture. They see, feel or taste this texture, normally in conjunction with their other types of synesthesia, and simply consider it to be one of the inherent properties of the sound. This can happen with all sounds or just some, but the sound-texture pairings are consistent.

A non-synesthete: they don’t normally perceive impressions of texture from sounds in their day-to-day life and they never think about it. However, if asked they would say that certain sounds correspond to certain textures rather than others.

Similar phenomena that are NOT auditory-tactile synesthesia:

Frisson (goosebumps or shivers of pleasure on listening to music).  Frisson is quite common and is a feeling of “shivers down your spine” and in the back of your neck. It can also produce tears or laughter and a speeded up heartbeat. It is estimated that perhaps two-thirds of the general population are able to feel this reaction (Grewe et al., 2007). It isn’t synesthesia but a physiological response to the emotion caused by the beauty of the music, particularly when it surprises the listener. It doesn’t normally happen with non-musical sounds. It has been associated with people who are more open to experience.

This video about the astonishing performance of the singer Susan Boyle after facing the contempt of a disrespectful jury and a sniggering audience in her trial for the TV programme Britain’s Got Talent is an excellent example of something that can cause frisson in many people.

ASMR ("Automatic sensory meridian response”). Some people experience a feeling of hypnotic pleasure and a relaxing tingling sensation in their head, shoulders and spine, sometimes spreading to other areas of the body, in response to specific auditory and visual stimuli such as the sounds of whispering or kissing, fingernails touching the microphone or watching scenes of personal care and activities carried out slowly and with concentration. The phenomenon began to enjoy popularity in the early 2000’s, attracting increasing numbers of followers who experienced it, and literally millions of YouTube videos are now dedicated to scenes intended to evoke it. The percentage of people who experience ASMR is not yet known, although it is clear that it those who do are not necessarily synesthetes. In fact, an interesting and rigorous research study (Barrat, E. L. and Davis, N. J. 2015found that 5.9% of their sample of people who experienced ASMR also had synesthesia, higher than that of synesthetes in the general population (around 4%) but not by any means exclusive or even typical. ASMR has been compared with auditory-tactile synesthesia but is not considered a manifestation of it, one of the reasons being because it creates a broadly similar reaction in all those who experience it and is therefore not idiosyncratic.

"Grima" or saccular acoustic sensitivity. This is an unpleasant sensation experienced on hearing certain sounds such as nails on a blackboard, scraping of textures like polystyrene or the prongs of a fork scratching a ceramic plate. It can put your teeth on edge and create a unpleasant shock sensation in the body including goosebumps and shivers, but it isn’t a form of synesthesia. It appears that all people can in fact suffer from it to a greater or lesser extent.

You can read more about this phenomenon here.

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This page last updated: 21 September 2021

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