Thursday, 14 March 2013

A group of 3 adults. Dyslexic or not? Change in reading performance .

A group of 3 adults. Dyslexic or not? Change in reading performance .

Yesterday I wrote that I would be working with adults at an FE college, who had difficulties with reading.  I have been interested for a long time in the difference between a person who is identified as Dyslexic and a person who may be dyslexic  but has struggled with text just as much as a person identified as dyslexic but been identified and then in the UK with a different level of support/intervention.

In Further education colleges, in the UK, there are now many people undertaking courses to try and improve their employment opportunities. Many of these are people who have had ‘doing the courses’ as a condition of their continuing to receive welfare benefits.

No one has ever actually recorded the literacy levels of this group of people, but improving literacy and numeracy this is a fundamental component of many of the courses.

The people I am working with attend a very forward thinking college in the UK. As a component of the course I am advising on analysing the participants in terms of trying to identify if there are any  limiting factors/barriers  to their reading performance which can be lowered or removed easily. This could lead to a step change in their reading performance.
My contribution  is to identify if there are any correctible visual processing barriers  which can be identified.  This connects with other posts concerning whether visual processing is limiting /controlling phonological processing for any of them and whether the limiting effect can be reduced.
Identification of dyslexia and  teaching strategies associated with that is left to my colleagues at the college.  In an  FE college, in the UK, the provision of funding support from an Additional Learning Support (ALS) fund is not dependent on a psychological  analysis/labelling process but on the professional assessment of each individual’s need.

What did I learn?
The three of them were quite different.  But before we start I should state that I could not get the binocular eyetracker to work which substantially restricted my analysis.  I think a connecting cable  needs replacing!

Student 1  (B)
Default Oral reading fluency….  81 wpm
Optimal font size reading fluency…104 wpm
% improvement/benefit……..  28%.
No response to changing background settings
Stamina /fatigue problems during the meeting probably associated with oculo-motor/ muscular management problems.

B had had problems at school, a slow reader and writer he could not keep up when the teacher was writing on the board.  Or if he had to copy it down, it was always wiped off before he could complete it.

 B was often told off for copying from the person sitting next to him. When trying to read by himself he always got easily distracted and needed to keep his finger on the page so that he knew where he was when he had been distracted.

 He has no problems concentrating on a computer game or with diagrams.  The concentration problems only happen when he is reading.

In school, when sharing a book, he regularly had to pretend that he had got to the bottom of the page when the person sharing with  him asked. 

‘ Have you finished yet? ‘
‘Can I turn the page over?’
He simply could not keep up.

When copying words off the board he could never keep up. The teacher would rub off/wipe the board before he could copy it down.

His writing was slow and very hard for him to read let alone his teachers
Reading would give him headaches at the front of his head particularly above his right eye.

His distractibility and slow speed eventually give rise to behaviour of school avoidance, marginalisation and eventually to persistent truancy.

He had come back into FE college to do a functional  Maths and English course.
So the questions to ask are

Is B dyslexic?
How do we help B?

His Tutor at the FE college he attends now had tried all basic interventions and did not believe he would be diagnosed as dyslexic, I was told later that he may be identified as Dyspraxic..  My job was to find out if anything had been missed.

So what was the evidence?

B  had been told by his optician that his vision is perfect. 20/20. He was tested at distance.

With close work there appears to be a convergence problem.  He needs to keep moving the book/computer away from his eyes to maintain ‘focus’.

  This does not appear to be true when he is gaming with his X-box.
Reading is quite a rigid, iterative process compared with graphical activity, it appears to put more stress on the muscles of visual system. Possibly because for a slow reader the sideways moving muscles are only contracting very short distances at a time, while the other four muscles on each eye have to keep the eye ‘on the line’ for long time periods. A slow reader will have to keep these at the same muscle tone for quite long periods. It must be similar to the effect on your leg muscles of having to walk slowly with tiny steps on an icy/slippery path. The muscle tone builds up, the joints and the muscles ache.
Fast. Fluent readers have much greater perceptual spans, so each saccade is over a comparatively longer distance and  changes of line , using the other muscles are more frequent.

Reading randomly sequenced short words aloud at a default font size of 12 on a ‘white’ background his RAN score was 81 wpm.( In work in schools, 80 wpm appears to be a cut off below which the children in the UK are normally given special needs support.)

Now this test has been used as a measure of phonological processing speed independent of total reading experience and virtually free of automaticity issues because of the short simple nature of the words, and no syntax component.  If this was just a measure of phonological output independent of visual parameters, it should give the same score as rapid digit naming which statistically appears to be true with adults we have tested before.

Reading meaningful text with short words and of course syntax which gives a clue of what the next word should be before you see it  B’s reading speed increased to 128 wpm.  The difference  here can  be argued as associated with the time /milliseconds, it takes for the visual system to identify a word being dependent on the probability of a particular word fitting into the logic/syntax of the preceding word string/ sentence and the mental constructs/ideas inherent in the body of text/associated graphics being accessed  ‘Close’.

Reading complex meaningful text, the same as we use with dyslexic undergraduates, with many more much longer unfamiliar words and more complex prosodic components his reading speed was 59wpm.  BUT importantly he was able to decode and blend all the words, it just took longer.
Reading this more complex text the words were longer approximately 5 characters per word on average compared with 4 characters per word in the simpler text.

So what the consequence of our meeting?

There was a clear response to changing the font size.  B read a block of randomly sequenced small words, repeatedly until  he had reached a maximum speed ( this is leaning/familiarisation with the task.)  When he had reached a maximum speed the font sizes were changed.  The data showed an increased in reading speed until a font size of 25 was reached after which there was a reduction in speed.

There was no clear relationship between screen background settings and reading performance.

What did happen though was a consistent gradual reduction in reading performance over time which masked any other factor.

It seems likely that there is an unresolved problem with vision at near, a convergence insufficiency which needs dealing with. He is to go to an optician and be tested at near.

We do not know how the optimal glasses will  affect his response to font size but the present need for a large font may be associated with crowding effects arising from the problems with binocularity.

I could have checked this by testing him monocularly but we ran out of time.
This would have also been a way of checking if the fatigue problems were linked with a convergence problem. Retrospective analysis is useful when a ‘rematch can be organised. I will have to do that.

Student 2  (D)

 D has never been to an optician
There appears to be an severe Astigmatism in her right eye and both eyes appear to be myopic with presbyopia affecting distance vision.
She has a problem of bilingualism and phoneme production. Until 9 years ago she had not read or spoken English.

RDN.. default….  148
RDN font 31…….   193
Benefit of larger font size……  30%
Ran  aloud default..117
Ran default silent( sub vocalising) …..  152
Ran font 31 ( sub vocalising) ……  193
ORF  default..  59 aloud   zero silent
ORF opt aloud    82   subvocalising  178.
Benefit……..aloud     ….39%
Benefit ..reading/any method……  202%
Optimal background white optimal font size 31

Lessons learnt

Her native language was Urdu. She started to read English in 2004.  Reading aloud is emabarassing for her.
At school she always needed to subvocalise and was told off for reading aloud/mumbling.
The limiting factor appears to be optometric AND font size. We do not know how much of the font size is a consequence of uncorrected optometric component.

She is able to decode and blend at her large font but at small fonts it is not blended as easily. This may be crowding affected by font size and associated spacing. We will not know that until she has the correct glasses.
Her left eye has a myopic fixed focus which will make reading at distance very difficult. Except with her astigmatic right eye.  The large optimal font may be associated with compensation for the uncorrected astigmatism.

If RDN is a measure of phonological processing then changing the font size has enabled faster phonological processing.  There was decoding of the numbers but no phonics in the sense of decoding and blending. So in the phonological processing increased by 30%.

If the oral reading fluency is considered , taking away the psychological worry about correct pronunciation ( sub vocalising)  At the default font she could not read by subvocalising. Aloud this went from 59 wpm to 82 wpm    a 39% increase. But since she could now read subvocally at 178 wpm this meant an effective increase in reading performance from 59 wpm to 178 wpm. An increase of  over 200%  . This may sound extreme but that was the outcome.

D will now go to an optician and get appropriate glasses. We can then check what her optimal font size is making use of optometric correction.

Student 3  (F)


 Default ( font 16) 

ORF…. 67 wpm
RDN…. 113  ( no crowding effects)

ORF …. 100
Benefit…….  49%

RDN…. 128.
Benefit…..  13 %

Optimum Settings

If we consider that the RDN involved no crowding effects compared with the ORF  then perhaps 13 % of the gain in Orf was associated with crowding.  The rest of the gain in ORF may have been associated with increased processing speed not linked to crowding.

F was able to read all of the texts offered but slowly. The normal sample text used with dyslexic undergraduates was used.

Student F responded to font size, as can be seen in the graph below. 

He also responded to changes in the background setting. But he only needed a very subtle change from white. To him the difference was immense. We needed to reduce the brightness of the red pixels but only by about 10%. All of the filters available commercially would have removed too much red or green  and blue as well. As such when offered them in a forced choice, or casual process, all of them would have been worse than white.  The outcome of course would have been a false negative.

F has now been diagnosed as dyslexic, it will be interesting to watch what happens to his reading performance as the support clicks in.

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