Auditory Nerve or IHC/OHC Damage?

[Meestijn]

Probably some strange/dumb questions but these thoughts been at the top of my mind quite some time now.

First the reason of my thoughts;
I have noice induced Tinnitus due to overexposed earbuds uses during the day (at least that is my believe).
First actually noticed with a high freq. noise (4kHz) pitch in my left ear, however, that pitch almost faded completely.
In return, it became more of a static/white noise all over of my head sound.
This noise is more active after being in (moderate) noisy environments.

Now my questions;
I'm now wondering whether this 'over'activity is because of the auditory nerve (lost neurons?) that can't find the corresponding damaged IHC/OHC or something alike and thus became even more hyperactive?

Or can it be that the auditory nerve (the spiral ganglion cells) is damaged?
Is auditory nerve damage possible due to noise exposure?

Or are some of the IHC or OHC are stimulated (agitated) and are on the brink of finally going down/dead so to say and thus may finally lead to a new higher level of T.

When it is auditory nerve damage then a threatment such as AM101 doesn't make sense, right?

Or is above all ridiculous thinking?

I hope my questions are clear, I can't describe my thoughts/questions better at the moment?

 

[Valentin]

Don't worry, you're not alone, eric and few others including myself sometime are having the same buzzing in our head, i believe the neurons are simply lost and have an erratic activity a bit like people having flash in their brains after head trauma...

 

[Karl]

My vote is

Or are some of the IHC or OHC are stimulated (agitated) and are on the brink of finally going down/dead...

In my opinion, that's how it starts. It's the IHC's that get "down/dead". Your auditory nervous system isn't damaged.

After the IHC's go down, the brain starts listening really hard to the down/dead IHC. The brain sends a signal to the down/dead IHC and the OHC, to "crank up the volume". This signal is a voltage on an efferent nerve which is connected to the back of the cochlea that is also connected to IHC. But the down/dead IHC can't crank up the volume. As a result, the brain "hears" only the signal that it sent to the IHC. It's a form of electrical feedback.

Some people say that tinnitus is like "listening to only the gain control of an amplifier". Or that tinnitus is like phantom limb syndrome. Whatever, the brain is listening to a signal that it is generating, in the absence of external information (sound).

If you can find a anatomical diagram showing how the auditory nerves are connected to the cochlea, you'll understand this theory of tinnitus. At the back of the cochlea, each IHC shares a connection with it's own afferent and efferent nerves. The IHC converts sounds into voltages, sending a current along an afferent nerve to the brain. The auditory system carries currents - it doesn't actually vibrate. If the IHC is damaged and can't generate a voltage, then it can't generate sound. But if a voltage on the associated efferent nerve is fedback to the cochea, then we will "hear" that voltage as a sound.

It is not well understood the purpose of the efferent nerves. But many people think these efferent nerves are used by the brain to compare sound levels between the left and right ears.

Drugs like AM101 claim to help people in the early stages of tinnitus. I don't quite understand this, myself.

 

[Meestijn]

My vote is

In my opinion, that's how it starts. It's the IHC's that get "down/dead". Your auditory nervous system isn't damaged.

After the IHC's go down, the brain starts listening really hard to the down/dead IHC. The brain sends a signal to the down/dead IHC and the OHC, to "crank up the volume". This signal is a voltage on an efferent nerve which is connected to the back of the cochlea that is also connected to IHC. But the down/dead IHC can't crank up the volume. As a result, the brain "hears" only the signal that it sent to the IHC. It's a form of electrical feedback.

Some people say that tinnitus is like "listening to only the gain control of an amplifier". Or that tinnitus is like phantom limb syndrome. Whatever, the brain is listening to a signal that it is generating, in the absence of external information (sound).

If you can find a anatomical diagram showing how the auditory nerves are connected to the cochlea, you'll understand this theory of tinnitus. At the back of the cochlea, each IHC shares a connection with it's own afferent and efferent nerves. The IHC converts sounds into voltages, sending a current along an afferent nerve to the brain. The auditory system carries currents - it doesn't actually vibrate. If the IHC is damaged and can't generate a voltage, then it can't generate sound. But if a voltage on the associated efferent nerve is fedback to the cochea, then we will "hear" that voltage as a sound.

It is not well understood the purpose of the efferent nerves. But many people think these efferent nerves are used by the brain to compare sound levels between the left and right ears.

Drugs like AM101 claim to help people in the early stages of tinnitus. I don't quite understand this, myself.

Thanks for your feedback.

So your theorie suggest that this type of T only can get worse. More IHC become damaged thus the more voltages we gonna "hear"?
Not a good prospect to be honest?

What if the auditory nerves becomes damaged or cut... will this then stop the sounds.
And yes, I know that there are cases where the auditory nerves have been cut but still phantom sounds been generated. But would that also be the case for T originated from damaged IHC? Since in some cases the phantom sounds disappeared after cutting the nerves?

 

[Karl]

What if the auditory nerves becomes damaged or cut... will this then stop the sounds

There are threads on this website about cutting the auditory nerves. I believe that for most people with tinnitus, if their auditory nerve is cut, their tinnitus stops. But not always.

More IHC become damaged thus the more voltages we gonna "hear"?

Unfortunately, it can get worse. That's why it's important to avoid situations that can damage hearing. But hearing loss doesn't always result in tinnitus. My 94 year old mother has very bad hearing, but she does not have tinnitus.

On the bright side, we can habituate with time. With time, for many people it becomes less and less an issue. The brain has ways of adjusting through neuroplasticity.