Yesterday’s edition of The Material World on Radio 4 featured a fascinating discussion on how the brain processes sound. Presented by the mercurial Quentin Cooper* the guests – Jan Schnupp from the University of Oxford and Sophie Scott from the Institute of Cognitive Neuroscience – discussed:
- how we select which sounds merit our concentration in a noisy environment
- how, through the one-dimensional information supplied by compressed airwaves hitting the ear drum, we detect location, distance, whether the source is moving and, if so, in which direction**
- how 20 millisecond chunks seem to be the choice of the brain for both auditory and visual processing – the constant refreshment of sound and vision gives us the illusion of a continuum
- foreign accent syndrome
- which parts of the brain become active when an impressionist is conjuring up the sound of of another person – or when a person is selecting different registers of the voice
The last of these topics is something we use so naturally in teaching that it is taken for granted:
- the tone used to gently nudge someone back on task
- the slightly more emphatic one used to highlight that what’s being said is a reminder and not the first mention
- the increased intensity which suggests that the behaviour is becoming an issue
- the complete re-orchestration required if we realise that there is a perfectly valid and blame-free source of distraction
You can download the programme here (the item begins halfway through the broadcast).
Further reading:
Sophie Scott working with impressionist Duncan Wiseby
Science Daily article on work by Jan Schnupp on the auditory cortex which could lead to improvements in hearing aids of speech recognition systems
Science Daily article on how we concentrate on one voice in a noisy room
More on the millisecond chunking of sound and the effects of silence, white noise and reversal of those chunks on perception
* “For me science isn’t a subject, it’s a perspective.”
** This process, for me, becomes more fascinating when considering that stereo hi-fi products essentially strive to create the illusion of what is already an illusion.