More “The Science Bit” that we’ve been researching during the course of making our new show THE NOISE…
One of the scientists we’re working with on this project is Professor Tim Griffiths – a Wellcome Senior Clinical Fellow and Professor of Cognitive Neurology at Newcastle University. My favourite article of his is “What is an auditory object” which you can read/download in full here. Broadly what the article deals with is…
Objects are the building blocks of experience, but what do we mean by an object? Increasingly, neuroscientists refer to ‘auditory objects’, yet it is not clear what properties these should possess, how they might be represented in the brain, or how they might relate to the more familiar objects of vision. The concept of an auditory object challenges our understanding of object perception. Here, we offer a critical perspective on the concept and its basis in the brain.
It’s actually quite profound in what it’s proposing and a great read if also (by its nature) quite technical and academic in places. And so following are notes (a synopsis) of my understanding of the main points, for anyone who might be interested. I’m embedding Simon Scott’s “_Sealevel.1″ from his brilliant album Below Sea Level for you to listen to while reading – I’ve listened to this record a lot while writing this show…
[soundcloud url=”http://api.soundcloud.com/tracks/60041393″ iframe=”true” /]
NOTES…
Object Analysis =
1. analysis of information corresponding to things in the sensory world
2. separation of information related to the object and information related to the rest of the sensory world
3. abstraction of sensory information so that information about an object can be generalised between experiences in one sensory domain i.e. it is possible to recognise the object in different environmental settings
Auditory object is not necessarily the sound source.
Auditory representation is a combination of the the source of the sound and “event information” .
An auditory object is therefore a particular voice, for example.
BOUNDARIES…
Objects need boundaries to identify them. Visual objects can be defined using two spatial dimensions. In the auditory domain, dimensions of representation are less well established…
Sound can be represented in both temporal and/or spectral domains. Either could define a boundary. (I think of this as being like wave/particle duality where a photon, for example, can be measured as both/either a wave and/or a particle – depending on how you choose to observe it).
If the cochlea constructs sound images in both domains at the same time (!) then an auditory object is a “complex two-dimensional pattern or image in frequency-time space, rather than a boundary in frequency or time alone”.
That’s a basic introduction to the paper! A startling (I think) attempt to define the physical boundaries of something you cannot see…