• Question: How and why can we blank certain sounds out after a length of time? eg if the radio is on but you are not listening to it, after a while you can't hear it unless you think about it?

    Asked by xxbethxx to Fiona, Jane, Joanna, Michelle, William on 20 Jun 2010 in Categories: .
    • Photo: Michelle Murphy

      Michelle Murphy answered on 17 Jun 2010:

      If you hear a noise for a long time and try to ignore it you are telling your brain that it is not important so while you continue to hear it unless something important crops up like your name your brain won’t pay any attention to the hearing receptors. Which is why, if you haven’t been interested in a class and a teacher asks a question and puts your name at the end you will just hear your name and have to admit to not paying attention and ask for the question again.

    • Photo: Joanna Brooks

      Joanna Brooks answered on 17 Jun 2010:

      Hey, thanks for your question! Well what you describe is what happens when the brain gets used to a certain sound – the brain simply blocks out the sound because you don’t need to pay attention to it. The brain is very clever at dividing your attention so that you can process the information you need as efficiently as possible. The sound becomes a ‘baseline’ or ‘background’ sound that the brain can tune out.

    • Photo: Fiona Randall

      Fiona Randall answered on 18 Jun 2010:

      Your brain can focus attention onto what is important. Once you have heard the sound and know it is not important attention can be moved away from it. But if you listened for it again you’d still be able to hear it.

    • Photo: William Davies

      William Davies answered on 18 Jun 2010:

      The attentional systems in our brain have evolved to notice changes in the environment. In terms of evolution, once we know that something is safe, edible, uninteresting etc. there is little point in still paying attention to it. However, if something new comes along, we need to assess rapidly whether it is dangerous, tasty, etc. and so need to pay attention to it for a short period

    • Photo: Jane Henry

      Jane Henry answered on 20 Jun 2010:

      There is loads of information coming at us all the time and we only consciously register a small proportion of the images and sounds around. We adapt (habituate) quite quickly to known sounds like a radio, so we can concentrate on something else. Experiments show we only hear one thing at a time, if you are listening to music and talking to a friends you are actually alternating between attending to the two and can favour one over the other.

Comments

  • Photo: Marianne

    Marianne commented on :

    The same happens with smells!

    Again, evolution; we need to notice things that could be dangerous. New sounds and smells are important information about the environment. Repetitive things aren’t likely to pose a threat, so we’re able to ignore them after a while as this isn’t likely to be dangerous.