cbcl mit g. geiger*, m-l. lorusso+, s. pesenti+, a. facoetti+# c. cattaneo+ and j. lettvin** *cbcl,...
TRANSCRIPT
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G. Geiger*, M-L. Lorusso+, S. Pesenti+, A. Facoetti+# C. Cattaneo+ and J. Lettvin**
*CBCL, Brain Cognitive Sciences, MIT, Cambridge, MA 02139 ** RLE, MIT, Cambridge, MA 02139+IRCCS “E. Medea”, La Nostra Famiglia, Bosisio-Parini, Italy#Department of General Psychology, Padova University, Italy
CROSS-MODAL PERCEPTUAL LEARNING AS DEMONSTRATED IN DYSLEXICS
Presented by Gadi Geiger
Poster shown in Vision ScienceS conference, Sarasota, FL, May 2001
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Complex task performance characteristically involves multiple-modal sensory perception.Would the learning of a new task by visual and visuo-motor practice also results in improved performance in the auditory-phnemic modality? Dyslexics (one group of 14 adults and another of 17 children) who were impaired in reading and phonemic abilities, were characterized by a wide region of visual attention. They practiced a regimen comprised of novel hand-eye coordination tasks (art work and the like) and reading single words with a mask (a small window in a blank sheet), together for 50 minutes to 2 hours per day over 4 to 8 months. As a result of the practice the dyslexics learned a new perceptual strategy, which was expressed by narrowing the region of visual attention and concurrently improved reading significantly. Tests of auditory-phonemic skills and reading of nonsense words (considered as a measure for phonemic awareness) also showed a significant improvement although auditory-phonemic practice was not included in the regimen. This improvement of the psycho-auditory skill as a consequence of a regimen, which includes only hand-eye coordination practice together with visual recognition of single words, indicates close cross-modal interactions. That suggests two possibilities. Either a strategy is sensory-modality specific, and once it is learned by that modality there can be a “spill-over” to other modalities by association. Or, there is a general perceptual strategy which governs perception, i.e. once a strategy is learned in one sensory modality it is learned for other modalities.
Abstract
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The first study was with 14 adult dyslexics (from a community college in Boston)
Average age: 23.2 (range: 18 - 38) years
The second study was with 29 Italian dyslexic children(from an outpatient setting in a hospital)
Average age: 10.5 (range 8 - 14) yearsaverage grade: 5th (range 3rd - 10th).
The Italian dyslexic children were divided into two groups:
1. The G-L practice group which had 17 dyslexic childrenand
2. the “Logopedia” group which had 12 dyslexic children These groups were comparable in age and grade composition.
The subjects
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For the adults: -Average or above average intelligence. -On the Woodcock-Johnson Revised (1989) sub tests
at least 2 grade levels bellow the expected level on reading.
The average initial scores are shown in the chart below. For the children: -Average or above average intelligence. -An overall reading and writing deficit of 2 SD (standard
deviations).-The tests included also visual, auditory and auditory- phonemic performances
The average initial scores are shown in the charts below.
Diagnostic criteria
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Our regimen of practice (G-L practice) is comprised of: - novel hand-eye coordination tasks (art-work and other fine work).- reading words in isolation with a mask (“the window”) as shown below. The adults practiced that regimen for an average duration of 6.5 months.
They practiced on average:55 min./day of art-work, and 30 min./day of reading with the mask.
All the children practiced for 4 months. The G-L practice group practiced our regimen.
An average of27 min./day art-work and15 min/day of reading with the mask.
The Logopedia group practiced language-therapy and
phoneme-awareness for an average of 40 min/day.
The regimens practiced by the dyslexics
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The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
Reading with a window-mask
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Reading with a window-mask
The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
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Reading with a window-mask
The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
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0-2-4-6-8-10
word ident.
comprehension
word attack
before
after
before and after practice
grades
Reading levels of 14 adult dyslexics
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grades
improvements
("0" is the expected level for each individual)
*
*
*
( * - denotes significance better than 0.05)
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20
40
60
80
100
The form-resolving field (FRF) of the adult dyslexics
angular distance from center of gaze [degrees]
corr
ect
reco
gniti
on
[%]
before
after
OR
before and after practice
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0-1-2-3-4
G-L practice
Logopedia
before
after
Accuracy of reading
SD
210
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SD
improvements
*
Reading of passages and word-lists by dyslexic children
(reading levels are indicated by standard deviation (SD) units from the expected norm)
0-1-2-3
G-L practice
Logopedia
before
after
Speed of reading
SD
210
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SD
improvements
*
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0-1-2-3
G-L practice
Logopedia
before
after
Accuracy of reading non-words
SD210
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SD
improvements
*
0-1-2-3-4
G-L practice
Logopedia
before
after
Speed of reading non-words
SD
210
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SD
improvements
*
Reading non-words
improvements
improvements
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86420
G-L practice
Logopedia
before
after
Fusing syllables to words
errors
420
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improvements
*
Measuring auditory-phonemic skills
6420
G-L practice
Logopedia
before
after
Omitting syllables from words
errors
420
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improvements
*
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1. a.The dyslexics who practiced our regimen (G-L practice) have improved reading skills significantly. b. The dyslexic children who practiced logopedia improved
less and the improvement was not significant. 2. The FRF of the dyslexics who practiced our regimen had
narrowed to resemble that of ordinary readers. 3. a. The dyslexics who practiced our regimen have improved significantly in their auditory-phonemic and the
phonemic-awareness skills (non-word reading). Although that regimen includes only hand-eye coordination tasks and recognizing words in
isolation. b. The children practicing logopedia did improve but not
significantly on these tasks.
Summary of the results
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- The dyslexics who practiced our regimen have learned a new perceptual strategy which in turn improved reading. -Learning this new strategy resulted in equal improvements in
reading and phonemic skills (auditory and reading related). Suggesting one of two possibilities: -There is a general perceptual strategy which governs perception. Once it is learned in one sensory modality, it is learned also for other modalities. -Perceptual strategies are sensory-modality specific. Once it is
learned by that modality it might spill-over to other modalities.
Conclusions
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The next slides, taken from Perception as Practiced, explainthe basic notion of the form-resolving field (FRF).
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The form-resolving field (FRF) of English-native adults
angular distance from center of gaze [degrees]
corr
ect
reco
gniti
on
[%]
ordinary readers (OR)
dyslexics
dyslexics
OR
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The form-resolving field (FRF) of English-native adults
angular distance from center of gaze [degrees]
corr
ect
reco
gniti
on
[%]
ordinary readers (OR)
dyslexics
the differences in recognition
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20
40
60
80
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The form-resolving field (FRF) of English-native adults
angular distance from center of gaze [degrees]
corr
ect
reco
gniti
on
[%]
ordinary readers (OR)
dyslexicsthe extent of recognition
difference
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The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
When ordinary readers look at text
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The way we see is not determined by what we want to see but how we have learned to practice seeing. There are several strategies that we pick between depending on what we have learned to see, and we switch between them as the task changes. So for example, a hunter uses a wide field of vision to locate prey,a scribe uses a narrow field to write and a painter or architectuses a variable field to arrange an ensemble into a whole. Eachdiscipline of seeing take practice. But suppose, like a dyslexic,you have a strategy inappropriate to reading.
When dyslexics look at text
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Demonstrating lateral masking
N x TENET
Keep you gaze on the x without moving your eyes