By letter or by word? Both quotations
have the same total contrast energy. In the first the energy is divided
equally among all the letters, making all the letters equally and independently
identifiable. In the second quotation the energy is divided equally among
all the words, regardless of their length. In principle, for a given noise
level, a known pattern's detectability depends only on its energy, so equal
energy words should be equally visible, but in fact the short words pop
out and the long words disappear. This shows that human readers cannot efficiently
integrate the energy across a whole word. Instead the word is identifiable
only when its letters are independently identifiable. (The quotes are In
the beginning was the Word
And the light shineth in darkness.) Pelli,
D. G., Farell, B., & Moore, D. C. (2003) The remarkable inefficiency of
word recognition. Nature 423, 752-756.
http://psych.nyu.edu/pelli/ |