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CROSS-MODAL PERCEPTUAL LEARNING AS DEMONSTRATED IN DYSLEXICS. 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
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CROSS-MODAL PERCEPTUAL LEARNING AS DEMONSTRATED IN DYSLEXICS 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 Presented by Gadi Geiger Gadi@ai.mit.edu Poster shown in Vision ScienceS conference, Sarasota, FL, May 2001
Abstract 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.
The subjects 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) years average grade: 5th (range 3rd - 10th). The Italian dyslexic children were divided into two groups: 1. The G-L practice group which had 17 dyslexic children and 2. the “Logopedia” group which had 12 dyslexic children These groups were comparable in age and grade composition.
Diagnostic criteria 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.
The regimens practiced by the dyslexics 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 of 27 min./day art-work and 15 min/day of reading with the mask. The Logopedia group practiced language-therapy and phoneme-awareness for an average of 40 min/day.
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 architect uses a variable field to arrange an ensemble into a whole. Each discipline 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading. 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading. Reading with a window-mask
. . word attack . . comprehension . . . after before word ident. . . -10 -8 -6 -4 -2 0 0 2 4 6 8 Reading levels of 14 adult dyslexics improvements before and after practice * * * grades grades ("0" is the expected level for each individual) ( * - denotes significance better than 0.05)
The form-resolving field (FRF) of the adult dyslexics 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] before and after practice before after OR
. . Logopedia . after before . . G-L practice . 0 1 2 -4 -3 -2 -1 0 . Logopedia . . after before . G-L practice . . -3 -2 -1 0 0 1 2 Reading of passages and word-lists by dyslexic children (reading levels are indicated by standard deviation (SD) units from the expected norm) Accuracy of reading improvements * SD SD Speed of reading improvements * SD SD
Reading non-words improvements improvements
. Logopedia . . after . before G-L practice . . 0 2 4 6 8 0 2 4 . Logopedia . . after before . G-L practice . . 0 2 4 6 0 2 4 Measuring auditory-phonemic skills Fusing syllables to words improvements * errors Omitting syllables from words improvements * errors
Summary of the results 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.
Conclusions - 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.
The next slides, taken from Perception as Practiced, explain the basic notion of the form-resolving field (FRF).
The form-resolving field (FRF) of English-native adults ordinary readers (OR) dyslexics 100 80 60 correct recognition [%] 40 dyslexics 20 OR 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees]
The form-resolving field (FRF) of English-native adults ordinary readers (OR) correct recognition [%] angular distance from center of gaze [degrees] dyslexics the differences in recognition
The form-resolving field (FRF) of English-native adults ordinary readers (OR) 100 80 60 correct recognition [%] 40 20 0 -15 -10 -5 0 5 10 15 angular distance from center of gaze [degrees] dyslexics the extent of recognition difference
When ordinary readers look at text 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.
When dyslexics look at text 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 architect uses a variable field to arrange an ensemble into a whole. Each discipline of seeing take practice. But suppose, like a dyslexic, you have a strategy inappropriate to reading.
Demonstrating lateral masking N x TENET Keep you gaze on the x without moving your eyes