It is inevitable that our hearing will deteriorate and this can be for many reasons but the most common is age related (presbycusis). By the time we reach our mid 60’s one in three people will have sufficient hearing loss to require a hearing aid. This loss can be due to trauma or anatomical changes and maybe accompanied by Tinnitus a condition of varying debilitation. Tinnitus is also associated with loss of high frequency acoustic perception.
Tinnitus varies from person to person, with many sufferers experiencing daily pitch variations. Most non invasive therapies are aimed at masking the symptoms and have poor or only short term success. Some advocate success with brain retraining (habituation) and CBT.
Periodicity & Hearing (a different approach)
Subcortical Auditory Periodicity describes the brain’s ability to perceive pitch from complex acoustic information and is the subject of much research involving several areas of the brain.
In addition to giving a sense of pitch to acoustic information, the auditory system has the capacity to give presence in free space to a sound which is given a high priority by the Central Nervous System to directing attention to the sound source and triggering primeval unconscious responses, important for survival.
There are very few natural sounds produced above 9 kHz yet we are born with the ability to hear frequencies much higher, around 20 kHz. The brain processes these frequencies which are harmonics of some lower fundamental sound to determine the direction of a sound source and prioritise its response. The psychoacoustic system in its complexity is assumed to be compensating for this loss and creating missing neural information as hearing ability deteriorates.
The majority of Tinnitus sufferers have an element of hearing loss more prominent above 8 kHz which is above the upper limit for a general hearing aid test. This high frequency acoustic information from broadband sound sources is processed into spatial awareness. It is understood that the brain can do this by processing differences of sound intensity and neural response time from acoustic information received by the left and right auditory systems. To do this requires the function of the outer ear (pinna) in conjunction with the anatomy of the skull. This part of the hearing mechanism is mostly bypassed when earphones or earbuds are used.
Is there a difference between hearing and listening?
Hearing is mechanical, the ability to convert micro changes in air pressure into electrochemical information. Whereas listening is making sense of this information.
Audiology specialists are in general agreement that hearing can be improved with listening exercises and can also improve cognitive performance.
Tinnitless will exercise the auditory and neural mechanisms involved in pitch perception and acoustic spatial awareness.
Weird but effective ways to hear better
Try the acoustic response test
If the pc’s audio system you intend using has amplified speakers the volume must be set low and may not have an ideal frequency response.
Laptop pc’s and Tablet pc’s are preferred and will have to incorporate flash player to use the app.
The High Frequency Acoustic Response
Test each ear individually from a sound source external to the head so not using earphones (free field), to determine the extent of any imbalance and or deterioration of acoustic high frequency perception.
Use sound blocking ear plugs to monitor one ear at a time
If you know which is your most sensitive ear, start with that one.
Set the pc volume to about half (see above warning), plug the poorer ear and click START. This will generate a reference tone which unless you have profound hearing damage will be heard in the range of the ear canal resonance frequency.
Set the dB attenuator so that the one second tone burst can be heard at a comfortable listening level. You may need to adjust your pc volume if it is near to the limit.
Repeat this procedure for the opposite ear trying to get the same sense of loudness by adjusting the dB attenuator at START.
Travel around the spiral with the mouse pointer starting at the outer most button, listening for the tone bursts that will decrease in acoustic frequency and be visable at the display, until they can be heard at a similar loudness.This can be repeated at different attenuator settings. Make a note of the frequency displayed and dB setting, then repeat this for the other ear so that for both the left and right you have two frequency values and two dB settings for the upper threshold span.
These upper threshold limits will show any deterioration in your hearing.
A small sample of bilateral acoustic tones are available for you to try by selecting one of the categories closest to your parameters and clicking on one of the three buttons below the (INFO) button.
The samples are fifteen minutes duration and should be listened to in a reasonably quiet setting without headphones, (a free field sound source) and at a distance of roughly one metre from the pc, positioned at chest to head height. Facing central to the screen, set the attenuator dB to be between the levels obtained for your left and right upper frequency threshold.
Click the mouse pointer on one of the three sample buttons that is closest to your parameters.
Get comfortable and try to keep your head relaxed and still, then listen for subtle changes to the tones that resonate with your left and right auditory responses. This sensation of spatial awareness comes with listening intently, usually within the first five minutes and is not due to a binaural beat effect, that happens only at frequencies of 1.5 kHz or lower.
Follow the Periodicity link below to our High Frequency Acoustic Response simulation (requires Flash)Periodicity
There were many books and journals that were referenced in the early design stages some of which I have listed with links below.
Making Sense of Sound
Weird but effective ways to hear betterMoreb
Auditory Training: Evidence for Neural Plasticity in Older Adults
Auditory Neuroscience Editor-in-Chief PETER DALLOS, Ph.D.
Tinnitus does not require macroscopic tonotopic map reorganization
DaveR.M.Langers 1,2*, Emilede Kleine 1,2 and Pimvan Dijk 1,2
Evidence for differential modulation of primary and nonprimary
auditory cortex by forward masking in tinnitus
Larry E. Roberts a, b, *, Daniel J. Bosnyak a, b, Ian C. Bruce a, b, c, Phillip E. Gander a, 1, Brandon T. Paul
Tinnitus pitch, masking, and the effectiveness of hearing aids for tinnitus therapy
International journal of audiology · November 2012
ANATOMY, PHYSIOLOGY, AND DISORDERS OF THE AUDITORY SYSTEM
Second Edition A. R. Møller
The Human Ear & Hearing, Sound Intensity and Loudness Levels
UIUC Physics 406 Acoustical Physics of Music
The Impact of Sound on Electroencephalographic Waves
during Sleep in Patients Suffering from Tinnitus
Marisa Pedemonte,n, Martı´n Testaa, MarcelaDı´aza, Diego Su´ rez-Bagnasco