trying again

[Elizabeth Bates]

>From bates  Wed Mar 21 08:18:08 2001
Date: Wed, 21 Mar 2001 08:18:08 -0800
From: Elizabeth Bates <bates at crl.ucsd.edu>
To: Pmv321 at AOL.COM
Subject: Re: Dyslexia
Cc: bates at crl.ucsd.edu, funknet at listserve.rice.edu

Interesting you should ask, since this issue was just in the newspapers
this week.  The answer is complex: (a) yes, dyslexics have been
diagnosed in many different languages, with orthographies as different
as Italian or Spanish (very transparent orthographies in which the
sound is predictable from the print), English and French (very irregular
orthographies with many unpredictable sound-print mappings) and
Chinese (a non-alphabetic, logographic writing system); (b) however,
the kind of orthographic interacts with symptoms, so that dyslexia has
much more complex and severe results in English or French, while
showing up primarily as a slowing in reading only for transparent
orthographies.  A study using a neural imaging technique (PET) by
Paulesu et al. (this week's Science) showed that there is under-
activation in the temporal lobes for dyslexics compared with
normals during a reading task, and that this activation is seen in
Italian, French and ENglish (in other words, despite the variation
in severity of symptoms due to orthographic differences, weak readers
show weak activation in the regions taht presumably have a lot to
do with extraction of sound from the signal).  What we CANNOT
conclude from this study is whether the temporal lobe areas are
defective in dyslexics (on biological grounds) or whether that
is just what a healthy brain looks like when it is reading badly
(so that I might show it in a language I don't know well, and
children might show it whenthey are learning to read).

My guess would be that there ARE dyslexics in Iran (defined as slow,
weak readers) but that there has not been much effort to diagnose
it as a disorder.  -liz bates