Poor sense of rhythm 'could be problem behind dyslexia'

      A poor sense of rhythm could be the problem that underpins dyslexia, 
      according to scientists.

      Dyslexic children appear less able to detect the "beats" in sounds that 
      pulsate rhythmically.

      Researchers believe awareness of beats influences the way children at an 
      early age assimilate speech patterns and this in turn is thought to affect 
      their reading and writing ability.

      The scientists, led by a team at University College London, tested about 
      100 children, including 24 who were classified as dyslexic by their local 
      education authority, by playing two kinds of sound to the children.
      One contained a rhythmical, rapidly pulsating beat while the other rose 
      and fell in volume at a much slower rate. Slow amplitude changes give the 
      impression of a continuous sound that varies in loudness, rather than a 
      distinctive "beat".

      New sounds were then played to the children through headphones, and they 
      had to decide if what they were hearing was similar to the first sound or 
      the second.

      The results, published in the journal Proceedings of the National Academy 
      of Sciences, clearly showed dyslexic children had trouble recognising the 
      rhythmic sound.

      Speech in all languages has a rhythmical beat linked to the points at 
      which sounds are perceived, called "P-centres". Musical sounds also 
      contain P-centres, but in speech they correspond to the onset of vowels.
      The researchers believe difficulty in recognising these speech rhythms is 
      at the root of dyslexia.

      Children who were unusually advanced readers for their age were strikingly 
      good at the beat-recognition test and the research hinted that one way to 
      treat dyslexia might be to train children by modifying recorded speech to 
      exaggerate the P-centre association with vowels.

      Story filed: 23:29 Monday 22nd July 2002
            
Source: http://www.ananova.com/news/story/sm_634409.html