How much audio processing does the brain do?

[Berwhale]

Not implying that at all. A brain is required, the question is how much does it modify the signal presented to it by your ears. Then a secondary question evolves: What are the results and effects of the modification? Its seems this has much more studied in the visual realm than the audio.

This question implies that your hearing organs are separate and distinct from your brain. It's not a simple as that: https://en.wikipedia.org/wiki/Auditory_system

 

[Cahudson42]

None whatsoever. Garbage in, garbage out...LOL

Hi Ron,
Elaborate a bit? Beethoven 7th as garbage in?

 

[Wombat]

FWIW

https://www.health.harvard.edu/staying-healthy/music-and-health

 

[Wes]

Yes, sure the answer to 'how much audio processing does the brain do?' is: all of it.

No, some is done in the ear.

 

[Berwhale]

No, some is done in the ear.

Where does the ear end and the brain begin?

 

[Ron Texas]

Hi Ron,
Elaborate a bit? Beethoven 7th as garbage in?

You missed the sarcasm.

 

[Wes]

Where does the ear end and the brain begin?

May I suggest a dissection?

 

[Kal Rubinson]

I assume there have been experiments that have 'Mapped' relatively low-bandwidth auditory input - say Beethoven's 7th - to higher bandwidth visual perception?

I cannot make sense of that question.

 

[raistlin65]

Not implying that at all. A brain is required, the question is how much does it modify the signal presented to it by your ears. Then a secondary question evolves: What are the results and effects of the modification? Its seems this has much more studied in the visual realm than the audio.

Are you using fast thinking or slow thinking with that statement, to borrow Kahneman's terminology?

 

[Kal Rubinson]

Where does the ear end and the brain begin?

The "ear" ends at the synapse between the haircells and the auditory nerve's distal axons. These axons, their cell bodies in the spiral ganglion and their central axons are parts of the peripheral nervous system. Those central axons enter the brain and synapse on brainstem neurons. So, technically, the "ear" and the brain are connected via elements of the PNS.

 

[Berwhale]

Interesting read... http://www.cochlea.eu/en/auditory-brain

 

[Kal Rubinson]

Interesting read... http://www.cochlea.eu/en/auditory-brain

Pretty simple but nicely framed.

 

[North_Sky]

The "ear" ends at the synapse between the haircells and the auditory nerve's distal axons. These axons, their cell bodies in the spiral ganglion and their central axons are parts of the peripheral nervous system. Those central axons enter the brain and synapse on brainstem neurons. So, technically, the "ear" and the brain are connected via elements of the PNS.

I was just about to say that.

Kal, how come you ended up being an audio/classical music technical reviewer instead of a neuro scientist climate activist?

 

[Kal Rubinson]

I was just about to say that.
Kal, how come you ended up being an audio/classical music technical reviewer instead of a neuro scientist climate activist?

Did neuroscience but retired in 2015. Now Emeritus and just having fun.

 

[Berwhale]

Did neuroscience but retired in 2015. Now Emeritus and just having fun.

Is this the intersection of Neuroscience and 3D Home Cinema? https://www.theguardian.com/science...shrimp-films-to-cuttlefish-in-3d-vision-study

 

[Here2Learn]

Odd question, as if to imply reality perception or sensations have any possibility of occuring without a brain..

Hmmm....

https://e360.yale.edu/features/exploring_how_and_why_trees_talk_to_each_other

 

[Here2Learn]

Where does the ear end and the brain begin?

Test with a drill. If you reach grey matter, you've gone too far!

 

[ElNino]

My question is how much audio processing does the brain do? Is what our ears perceive what we actually think we hear?

From a technical perspective, the processing done by the human auditory system is very interesting. If you've read about the hairs in the ear (stereocilia), you probably realize that the ear isn't a simple time-domain transducer like a microphone (some people think the eardrum is like a microphone, but that's not its function). But the ear also isn't a frequency-domain transducer, that is, the stereocilia aren't arranged in different lengths with the brain performing the equivalent of an inverse Fourier transform. Rather, they're all roughly the same length and as sound waves make the basiliar membrane move, they all feed into the auditory processing. The closest conceptual thing if you're into signal processing is actually probably aperture synthesis, the way several small antenna are combined in a big radiotelescope. Which might not be as unusual sounding as you think, since we know insects with hundreds of compound eyes kind of do the same thing for visual stimulia, and it's kind of cool that that eyes and ears found similar solutions in different species.

IMHO it is really extraordinary how much processing the brain actually does.

To get an intuitive sense of just how complex the processing needs to be, this page has a good animation of one example: https://auditoryneuroscience.com/acoustics/bm2-isolated-clicks The lower image shows which areas of the basiliar membrane move over time (think of stereocilia as "reading" info from the y axis) just to sense an impulse. Even though the basiliar membrane is designed to be sensitive to different frequencies at different places, the frequency range it directly senses is actually fairly narrow (about 6kHz to 400Hz), so to derive the entire range of human hearing (20Hz-20kHz) involves a complex analysis combining signals over the whole length of the membrane over a period of time.

 

[Kal Rubinson]

Test with a drill. If you reach grey matter, you've gone too far!

It depends how you orient the drill.

 

[Wes]

drill and a bone punch

add a really good vacuum cleaner and...