• Question: Within the superior temporal gyrus the primary auditory cortex wich processes sounds via its ability to proccess specific frequencies allowing us to comprehend sounds. I understand this ability is based on the existence of a tonotopic map. if this is similar to the homunculus 'map' of the primary motor cortex which is said to change through out the course of an organisms life, in the developing mind does this tonotopic map also change in chemical makeup as an organism is subjected to exterior accents etc thus changing the composition of other areas of the brain such as the Wernicke's area for pure language comprehension or is counter to this with other areas of the brain dictatuing this areas makeup? In either case what could the most important interior parameters in the brain be to allow the most accute development of language comprehension and accent development (ie, composition of conductiver tissue)?

    Asked by myrmefoot123 to Damien, Rachael, Suzi, Tim on 22 Jun 2011.
    • Photo: Suzi Gage

      Suzi Gage answered on 22 Jun 2011:

      Hi @myrmefoot123
      Did you write this question yourself? πŸ˜‰
      Great question!

      I’m afraid I don’t know whether your hearing parts of the brain change as you develop, in the same way that your sensory and motor brain areas do…
      Your brain when you are born starts off with a lot of extra connections and these disappear as you develop, leading the brain to specialise, so it may be as you say that this ‘pruning’ as it’s known leads to areas like Wernicke’s area becoming purely language areas.

      I don’t know what brain conditions you’d need to allow the best language comprehension I’m afraid – but Tim or Damien might?

      What do you think?

    • Photo: Tim Fosker

      Tim Fosker answered on 22 Jun 2011:

      Hi @myrmefoot123

      Wow what a long, but fantastic question! Your right about the tonotopic representation of the auditory cortex, but I don’t know much research on it changing. I seem to remember a study a few years ago looking at tonotopic representations in musicians, but I can’t remember what they found – I will try and look it up.

      Getting the best development of language comprehension involves a complex language network. People often talk about Wernicke’s area for language comprehension because it is a classic finding in patient studies, however many other areas are involved in comprehension. One current theory about the auditory aspects of speech is that the slow parts of speech (low frequency), like what you hear if you listen to someone through a wall, are processed in the right hemisphere and the faster parts in the left hemisphere. The slow aspects of speech seem to be very important to understanding speech. Andrew Oxenham has some brilliant sound examples of how important the different rates of speech are to understanding the speech. Let me know what you think?

      http://research.meei.harvard.edu/chimera/index.html

      I hope this has answered your question.

Comments

  • Photo: myrmefoot123

    myrmefoot123 commented on :

    Yes I did write this myself thank you Suzi!  Tim that was perfect thank you! I was reading around the subject as I am more predominantly interested in entomology but came across this fascinating but confusing topic. I have recently been looking at slides of larger insect brains and although rather unscientifically been comparing the sizes of the sort of prefrontal cortexes I have been able to find. with limited success! Whilst researching possible developments the brain undergoes throughout an organisms lifespan I found this curiosity and thought you might be able to help decipher it. Thank you so very much!

    • Photo: Suzi

      Suzi commented on :

      Aw sorry @myrmefoot123 I was only kidding πŸ˜‰ Hard to get across in text!

    • Photo: Tim

      Tim commented on :

      No problem at all. I’m very interested in how we extract speech from simple sounds so I love thinking about these things.

      I was interested in entomology when I was doing my A-levels, but mainly because we didn’t do much human biology on my course. I did a project on pill bugs (woodlice) – when I started I didn’t realize they were actually crustaceans and had a system more like gills! I had no interest in plants back in school, I thought they were boring, but my wife is a botanist and she’s changed my mind about plants altogether! πŸ™‚

      It is great you have enthusiasm for an area of research, good luck with all your research!