Lecture 23; Tinnitus Flashcards
What is tinnitus?
Perception of sound not in the presence of sound.
Ringing
Describe the features of a pure tone audiogram that would indicate what it means?
The banana represents the potential Hz and db of speech
The solid black line represents hearing threshold. Anything below it is heard. The more banana below it, the more speech that can be heard.
How would a hearing loss that still has some speech/ IHC function be rectified?
Hearing aid use
How do hearing aids function?
The tune up sounds in a intensity and frequency specific manner
What do hearing aids aim to do?
Replace OHC function that doesnt exist.
Are hearing aids useful for IHC damage?
No, in this case, cochlear implants are used to stimulate the auditory nerve directly.
Describe how a cochlear implant works;
Outer unit; Detects sound Hz and intensity, then conveys this information via magnetic transduction to the internal unit
Internal unit; Surgically implanted. Stimulates auditory nerve in the inner ear.
Will a person who recieves a cochlear implant hear immediately
No, they will need to learn to hear again
if a child is born deaf, when can they recieve a cochlea implant?
Before five years of age, after this the cochlea implant will not be able to function
If an adult has sudden hearing loss, when should they receive a cochlea implant?
As soon as possible, the longer they go without implant the less likely it will be successful.
When a deaf child receives a cochlear implant, what happens to tonotopic representation?
In the auditory cortex it goes from being disarranged to somewhat arranged over time as it adjusts to the input from the cochlear implant.
What is phantom sound?
Tinnitus
What are the types of tinnitus?
True tinnitus (phantom perception)
Objective tinnitus (somatosound)
What is objective tinnitus?
True sound, normally created by blood flow near the ear creating turbulence, due to proximity near the hearing organ it can be heard.
How does tinnitus differ between females and males?
Males are more likely to suffer from tinnitus (work place history) - and have a hearing loss associated..
Females are more likely to have tinnitus in their sleep
What is tinnitus associated with?
Hearing loss, but not caused by it.
Recording the auditory nerve shows what with tinnitus?
A reduction in nerve activity.
However further up the auditory system the brain is seen to increase nerve activity as if it is compensating for the reduction.
What is seen in the auditory cortex with tinnitus?
A spike in spontaneous depolarisation and activity.
Using a resting MRI what is the difference between a tinnitus and normal person?
Normal; Small areas of activation
Tinnitus; Large activation in auditory cortex and a lot of other regions. ( association with memory, distress, perception, somatosensory system ) (disassociation with visual system)
Why are some many parts of the brain active in tinnitus?
- Tinnitus is a sound that cant be explained by previous knowledge or any other sensory input.
- Auditory brain is strongly associated with survival reflexes…
What are the psychosocial impacts of tinnitus?
- Constant state of anxiety
- Attention towards tinnitus
- Anger
- Frustration
- Poor communication
- Tension
- Lack of sleep
What is signal detection theory?
If there is a sound present our personality will determine if we hear it or not.
What is the treatment for tinnitus?
Combination of counselling and sound stimulation
Based on assessment of patient = goals and desires.
What is the goal of counselling for tinnitus?
To remove the fear of the sound
Attention distraction
What is sound stimulation / therapy
I.e Masking
Use a pleasant sound to mask the tinnitus, through the use of hearing aids.
Does masking fix the problem instantly?
It can reduce the tinnitus rapidly but it takes a long time for the effects of tinnitus to reduce
Whats other ways of tackling tinnitus?
DP stimulation, using electrodes, but this is temporary as over time hyperstimulation can occur elsewhere in the brain.
How can the brain be stimulated remotely to stop tinnitus?
Transcranial magnetic stimulation (running low level current through the brain)
It only lasts 24 hrs and is hard to precisely active the correct region
What other nerve could be targeted?
Using a vagus cuff, target the vagus nerve to rest and stop tinnitus but requires surgery.
Can drugs be used for tinnitus?
MDA or ectasy.
Placebo, but havent trialled high doses yet
How can games be used?
If you listen to the tinnitus you get punished, rewarded for not paying attention.
Modifying behaviour technique
