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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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slide1

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

slide2

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.

slide3

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.

slide4

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.

slide5

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.

slide6

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.

slide7

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

slide8

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

slide9

.

.

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)

slide10

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

slide11

.

.

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

slide12

Reading non-words

improvements

improvements

slide13

.

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

slide14

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.

slide15

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.

slide16

The next slides, taken from Perception as Practiced, explain

the basic notion of the form-resolving field (FRF).

slide17

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]

slide18

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

slide19

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

slide20

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.

slide21

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.

slide22

Demonstrating lateral masking

N x TENET

Keep you gaze on the x without moving your eyes