X-Message-Number: 11456
Date: Wed, 24 Mar 1999 18:40:04 -0500
From: Jan Coetzee <>
Subject: Right brain also reads

The case of a 73-year-old stroke patient suggests that, contrary to
conventional theory, the nondominant side of the brain might play an
important role in reading, according to a report in the March issue of
the
Journal of Neurology, Neurosurgery, and Psychiatry.

Neurologists have long believed that processes involved in reading occur

solely within the left hemisphere of the brain, which is dominant in
right-handed individuals.

However, in right-handed individuals, the right brain may help process
"different spatial patterns used while reading," conclude Drs. R.R.
Leker
and I. Biran of the Hebrew University-Hadassah Medical School in
Jerusalem,
Israel.

The Israeli team report the case of an elderly right-handed professor,
fluent in both Hebrew and English, who was admitted to the hospital
after
suffering a hemorrhage in the right side of his brain.

Upon recovery, the man "complained of being unable to read simple words
or
paragraphs from a daily newspaper in Hebrew," the authors explain,
"whereas
he noted no such difficulty while reading in English."

Hebrew and English are each read horizontally, but in opposite
directions
(Hebrew right-to-left, English left-to-right). According to Leker and
Biran,
the man complained of "a fluttering motion" in his field of vision,
affecting "the rightmost letters of every word... when trying to read in

Hebrew."

Linguists believe that the first few letters of any word hold the 'key'
to
its meaning. The authors speculate that "the fluttering in the right
(field
of vision) may have been responsible for (the patient's) inability to
read
the all-important first letters string and to comprehend Hebrew words."
Such
a visual deficit would have little impact on left-to-right English
comprehension, however.

The man's reading ability eventually improved to near-normal, although
the
researchers note that "18 months after the (episode) he still had minor
deficits when reading Hebrew."

The researchers theorize that the right hemisphere may help us visually
place words and sentences in a right-to-left spatial frame. Damage to
these
spatial centers in the right brain might therefore trigger reading
deficits
in specific languages, they explain.

The case of the bilingual professor suggests "that the right hemisphere
does
play a part in reading ability and that this part may have special
relevance
to different spatial patterns used while reading," the Israeli team
writes.

"Different neuronal networks responsible for the direction of reading
may
come into play. We suggest... that lesions of these systems can cause
directional dyslexia," they conclude.

SOURCE: Journal of Neurology, Neurosurgery, and Psychiatry
1999;66:517-519.
_______________________________________________________________

J.C.

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