Rainer Machné / Version 0

Shshshshshshs, ngngngngngngn, ssssssss, iiiiiiiiiii ………. tinnitus can come in variously annoying, tedious or soul-destroying forms.

Interestingly, everyone ‘has’ some mild form of ‘tinnitus’, most people just don’t hear it. If you place yourself in a completely silent room, it will only take a few minutes until you can hear loud and clear the same noises that sufferers are unable to stop. Loud music lovers know this only too well. As a disease at the interface between mind and matter, tinnitus is notoriously hard to handle with current western medical methods.

Acoustic waves are basically rhythmic pressure waves, that let the molecules of their substrate dance around their resting position, in principle with unconfined amplitudes. The eardrums move with the air (or liquid) and drive the fine ossicles in the middle ear. The inner ear, the cochlea, is filled with a curious gel-like liquid – the endolymph – consisting mainly of negatively charged and thus highly hydrated sugar polymers – vertebrate specific hyaluronic acid and others. The fascinating electro-chemical properties of such substances might be involved in the electro-mechanical conversion by which hair cells in the organ of Corti decode the frequency and amplitude of acoustic waves. Coordinated hair cell movement in the vibrating endolymph can even employ stochastic effects to amplify low amplitude signals that are one order of magnitude lower than Brownian motion. Auditory nerve cells connect via synaptic contacts to these hair cells, that swing with the sound. Analogous to artificial sound detection, mechanical vibrations are converted to electrical signals, to be processed within the central nervous system of the brain in our case. Human listening, hearing.

While some forms of tinnitus can be relieved with surgical manipulation – resurrection of buckled hair cells, in most therapies the patient is more or less successfully trained to ignore the sound, filter it out mentally. Stress is a seriously worsening condition, but naturally is in a positive feedback cycle, a rather vicious one, with tinnitus. The exact relation between organic and psychological contributions are far from understood.

Sound perception at and below the lower frequency borders of human hearing (~20 Hz, but individually varying) transgresses a distantly related mind/matter border, although in this case the whole body itself becomes the sensory ‘organ’. It is unclear whether and how low such infrasound could at least in principle (mechanically) be sensed by the cochlea’s hair cells. At high amplitudes low frequencies become noticeable for the mechanoreceptors in and below the skin; you can feel the vibration. Fascinatingly, the eigen-frequencies (resonance frequencies) of many organs seem to lie in very low ranges and it is feasible that organic resonance oscillations might be a basis for a wide range of observed phenomena as well as a subject of various urban and older legends. Elephants and marine mammals produce infrasound frequencies for long distance communication, while migratory birds have been speculated to orient by infrasound signals of earth and atmosphere. Indeed, highly energetic movement of large matter usually evokes low frequency waves. The earth and the atmosphere constantly rumble inaudible to human ears. The infrasound of earth quakes, volcano eruptions and nuclear bombs can be detected over global distances. A car’s infrasound emission has been related e.g. to nausea in driving, while the foehn wind falling from mountains and heated by friction is likely suspected to disturbingly act via infrasound on human wellbeing; even super-natural experiences and ghost encounters in older and newer English haunted houses have been ascribed to infrasound sources. Cathedral organ pipes that produce infrasound are known at least since the late sixteenth century: awe of God through the finger on the key. Unlike tinnitus noise, infrasound waves cannot be heard but sensed which seems to take you from calm to uncomfortable, anxious or even sick. When it’s an earthquake, that might be of no consequence.