Cochlea
January / March 2018
Group Project with Shivam Bhatnagar, Lidia Dynes Martinez, Ben Greenberg, Jacob Mitchell and Ben Pheifer
The installation 'Cochlea' demonstrated the effects of hearing loss while listening to music. Cochlea creates a visualisation of an auditory experience.
HOW DO WE HEAR SOUND?
1.
To hear sound, the outer part of our ears, the pinna channels sound waves down the ear canal to the ear drum.
2.
This vibrates the ear drum, moving some tiny bones called the stapes.
3.
The stapes generate tiny pressure waves in the cochlea, a coil in the inner ear.
4.
The cochlea is lined with over 20,000 fibres of increasing resonant frequency from the centre outwards.
5.
When the pressure waves trigger these fibres, they cause hair cells to vibrate, sending electrical signals to the brain for processing as noise.
Frequency of sound heard along the cochlea in Hertz
HEARING LOSS
Auditory Processing Disorders
The problem lies in the brain, it cannot process the information received correctly
Sensorineural Hearing Loss
The cochlea gets damaged, rendering it unable to send signals to the brain properly
Conductive Hearing Loss
A problem in the outer or middle ear stops sound being passed to the inner ear properly
Mixed Hearing Loss
Both conductive and sensorineural hearing loss occur together
For this project, 2 causes of hearing loss were modelled:
Presbycusis
The sensorineural hearing loss occurs naturally as people age. Sufferers lose the ability to hear higher pitched sounds.
Noise Induced Hearing Loss
Hearing Loss that is caused by exposure to loud sounds for an unsafe length of time. It affects frequencies in the range 2 to 6 KHz.
!
dB HL is a unit to measure what proportion of sound can be heard compared with perfect hearing
Max 7, a visual coding software was used to model the 2 types of hearing loss
The raw dB Hearing Levels were converted into multipliers to apply to corresponding frequencies of sound using this equation.
Noise Induced Hearing Loss
Presbycusis
Once the audio track with the selected frequencies removed had been generated, the corresponding portions of the cochlea were illuminated.
An interface was developed for audience members to control the exhibit
CONTRIBUTION
- Max 7 code patches to generate the filtered audio tracks
- Hearing loss research
- Liaising with an expert audiologist