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Basketball Players Make Bad Jockeys: When a Strength Is a Weakness: An Approach to Understanding the Double Deficit Hypothesis

By Emerson Dickman, JD

“When you cannot measure it when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science.” -William Thomson, Lord Kelvin (1894)

INTRODUCTION:

The core deficit with which an individual with dyslexia must contend is phonological processing. Perhaps this concept may be better expressed by saying that: The independent variable with the greatest influence on the development of reading skills is phonological processing. The reason for rephrasing this concept is that not all the independent variables negatively influencing the development of skill in reading may properly be identified as “deficits.” “Too much of a good thing” is often ascribed as the cause of something bad. An overabundance is as negative as an insufficiency when the outcome sought is balance or harmony.

What got me thinking about the discussion that follows was a personal inability to rationalize the existence of certain phenomena with what I know about reading and dyslexia. Correlations were made for these phenomena and reading failure, but no cause to effect link or common variable was identified; at least to my satisfaction. Recently, my attempt to understand the problems many dyslexics have with rapid automatized naming and Maryann Wolf’s work on the “Double Deficit Theory” has helped me to conceptualize a theory that has, in turn, helped me to resolve my confusions regarding those other insufficiently, at least to me, explained phenomena. Therefore, even though the Double Deficit Theory was where I ended up, I will start my discussion with that issue (LIFO).

DOUBLE DEFICIT:

I suggest that the explanation of the correlation between poor performance on the RAN and reading difficulties is not a double deficit, but a deficit coupled with the strength of sufficient synergistic salience to result in compounding the impact of a deficit in phonological processing, through neglect.

The naming speed deficit (not due to scanning, IQ, or articulation deficits) may be due to visual ambiguities.

  1. Dyslexics often have superior visual-spatial skills (better than average). (In fact, Wolf’s research has shown that those with naming speed deficits have better than average – “absolutely superior” visual-spatial skills.) “[E]qually important might be an unusually strong right hemisphere with highly developed spatial skills.”(Masland, 1975).

  2. Persons with good visual-spatial skills are adept at seeing different visual perspectives and thus may see an ambiguity in the recognition symbols or objects, that others with lesser visual-spatial skills may not, e.g., Anything “Esher,” bd-p-q, 2-5, 9-6, 3-E, M-W, S-Z.

A. Visually ambiguous symbols (Have different meaning depending on spatial orientation.)

  • Lowercase letters: b d g l m n p q s u w z

  • Uppercase letters: E l M N P S U W Z

  • Numbers: 2 3 5 6 9

B. Less ambiguous symbols (Have meaning in only one spatial orientation.)

  • Lowercase letters: a c e f h j k r t y

  • Uppercase letters: B C D F G J K L Q R

  • Numbers: 4 7

C. Unambiguous symbols (Have same meaning in more than one spatial orientation.)

  • Lowercase letters: i o v x

  • Uppercase letters: A H O T V X Y

  • Numbers: 1 8 0

  1. The more you can see, hear, or feel (i.e., the more stimulation you perceive), the harder it is to distinguish between stimuli, i.e., it’s easier to find the salt if there is nothing else on the table. Therefore, if your mind can perceive a particular symbol (e.g., b) as being meaningful in more than one spatial orientation (e.g., b d p q), the mind must eliminate those orientations that are unintended in order to distinguish that which is intended. (In other words, there are 4 vessels on the table, one contains salt and 3 contain pepper. The only way to tell them apart is to look more closely than would be necessary if the salt was alone on the table.)

  2. Therefore, the “temporal gap” between “scanning” and “articulation” (interstimulus interval) is greater for those with the skill to perceive symbol ambiguity.

[Note: An interesting result might be achieved by using a “less ambiguous” or an “unambiguous” RAN and comparing it to an “ambiguous” RAN. Also I would predict right hemisphere activation if the RAN was administered during a fMRI š no need for subject to articulate a response (possible cause of artifact) since it is known in advance that a naming speed deficit exists.]

BRIDGE:

For years respected scientists, notably Geschwind and Masland, have espoused the proposition that difficulty reading may be the result of a combination of independent variables.

Gordon Sherman is fond of quoting Dr. Norman Geschwind as stating “high talents are overrepresented in dyslexia.” Geschwind often referred to what he termed the “pathology of superiority.

Dr. Masland quoted a biographer of Einstein as suggesting that:

“A noted deficiency should alert us to look for a proficiency of a different kind in the exceptional person.”

(Masland, 1975, p15)

“These findings suggest that the characteristics which predispose to reading disability would be first a weak left hemisphere with which there might be poor language structure and limited sequencing skills. Or equally important might be an unusually strong right hemisphere with highly developed spatial skillsá”

(Masland, 1975, p14)

Geschwind has stated that the disadvantages of dyslexia “may be fundamentally linked to the advantages.”

“many dyslexics have superior talents in certain areas of nonverbal skill. The immediate naive presumption is that success in these fields is simply the result of compensatory achievement in nonverbal fields on the part of those who do not succeed in readily acquiring reading. I believe that this explanation must convey at best a very small fraction of the truth.”

(Geschwind quoted in West, 1991, at 20)

It is Geschwind’s “pathology of superiority” that is attempted to be identified and explained in this discussion.

HYPOTHESIS:

The relative superiority of visual-spatial ability impedes the development of reading skills.

All other independent variables being constant, the better the individual’s visual-spatial skills the worse will be the individual’s reading ability. Put another way, reading ability and visual-spatial skill are inversely proportional. Why?

  1. 1. The individual with superior visual-spatial ability has difficulty interpreting ambiguous orthographic symbols (al la Rapid Automatized Naming).

  2. The individual with superior visual-spatial ability tends to over rely on nonverbal cues in oral discourse at the relative expense of developing word to meaning associations.

  3. The individual with superior visual-spatial ability tends to over rely on the ability to assume perspective (e.g., psychological, philosophical, ethical) of others involved in oral discourse to the relative expense of developing word to meaning associations. [Note: Researchers interested in the mechanics of psycho-social development have noted that the ability to understand another person’s point of view and the ability to recognize different visual perspectives generate from a common basis.]

  4. Such an individual would have the relative ability to ascertain meaning in oral discourse with a relatively lesser need to make word to meaning associations would also have a relatively lesser need to rely on grammatical form and make syntactical associations in order to arrive at meaning.

Therefore, everything else being equal, the better an individual's visual-spatial skills, the worse his reading ability is likely to be.

This hypothesis is based, in part, on the assumption that a strength in one context may be a weakness in another context (a good basketball player makes a bad jockey) and that a specific strength can often compound the impact of a specific weakness (the strength gets exercised and develops while the weakness is neglected and atrophies, e.g., amblyopia). [A weightlifter sacrifices flexibility for strength š muscle-bound.]

Oral discourse involves spoken words and nonverbal cues to impart meaning and comprehension. A dyslexic who has a phonological processing deficit and a visual-spatial strength relies on nonverbal cues to discern meaning from oral discourse. They are very good at it. Their attention to the subtle needs of the person with whom they are communicating is often described as empathy, sensitivity, and caring. But, at what cost?

Spoken words together with nonverbal cues are the code for the meaning intended to be conveyed in oral discourse. The person who relies more heavily on nonverbal cues is at a disadvantage in obtaining meaning from the written word. The written word is, after all, a code for the spoken word absent nonverbal cues. The dyslexic with visual-spatial strengths is likely to appear resistant to treatment because even if you teach him how to decode orthographic patterns into spoken language, he still lacks the ability to efficiently decode spoken language into meaning. Similarly, a person with apparently adequate phonological processing skills may exhibit an unexpected difficulty reading due to a relative strength in visual-spatial ability.

PARADOXES AND THE PATHOLOGY OF PARADIGM:

An old wallpapering trick is to connect two parallel runs of paper together with a wavy line if you can’t match the pattern. Why? Because our eye is so used to seeing a straight line that it overlooks the wavy line and since it doesn’t perceive the connection of the two pieces, it doesn’t recognize that the pattern doesn’t match at the point where the two pieces meet. (Try it, it works.) The point, I think, is that truth can be right in front of us and we will not see it if such truth is foreign to our experience and expectations.

“The dyslexics had significantly higher scores than normally achieving readers on the orthographic awareness task.”

Siegel et als, 1995 p. 250

After testing 257 dyslexic and 342 normal readers Segal et als theorized that dyslexics use “a reading strategy that relies more on the visual than the phonological features of words” (Siegal et als, 1995, p. 250). This conclusion appears to be the result of natural predilection to assume that we use strengths to compensate for weaknesses. In this study it is more likely that the strength is part of the weakness profile by slowing processing speed, due to the recognition of visual ambiguities in addition to causing the individual to neglect the development of a spoken word to meaning repertoire.

A variety of apparent paradoxes have puzzled researchers for decades. These paradoxes have been addressed in an unfulfilling and less than convincing manner by scientists attempting to fit all factors correlated to unexpectedly poor reading skills into a developing paradigm based on a deficit perspective. In other words, if you can’t do something that other skills and abilities would predict you should be able to do, it’s because something is wrong, not because something is right.

  1. Brain Symmetry:
    The average human brain is not symmetrical. The Planum Temporale in the left hemisphere is normally slightly larger than in the right hemisphere. It appears that the dyslexic brain is anomalous because the Planum Temporale in both hemispheres is the same size. Common sense would normally tell us that the Planum in the left hemisphere, where the language centers are located, would be smaller, thus accounting for the symmetry. In fact it appears that the Planum in the right hemisphere of the dyslexic’s brain is larger than expected. Visual-spatial skills and abilities are located in the right hemisphere.

  2. Cognitive Profile:
    The cognitive profile most often seen in the dyslexic is a WISC-III profile where the Performance IQ is greater than the Verbal IQ. On the surface, this doesn’t appear paradoxical until one recognizes that the Performance subtests are not only the better measure of visual-spatial skills but also most sensitive to reading problems, i.e., Picture Arrangement (use of reading to learn), Object Assembly (phonetic analysis), coding (code concept). Assuming that an individual has not suffered diminished scores on the Verbal subtests due to lack of benefit from the educational opportunities presented (a Matthew Effect), the WISC profile common to the dyslexic would be more indicative of good visual-spatial skills than reflective of poor language or phonological processing skills.

  3. Rapid Naming:
    The performance of dyslexics on rapid naming tasks has posed a dilemma for years giving experts fits. Dyslexics do poorly, but not because of a phonological processing deficit. Therefore, based on the paradigm that deficits result in poor performance, the scientific community has assumed that a second deficit exists, i.e., the Double Deficit Theory. As discussed previously, if ambiguity slows processing and visual-spatial ability promotes ambiguity, it is a skill not a deficit that results in poor rapid naming.

  4. Mirror Writing:
    Mirror writing, reversals, backward reading (“was” instead of “saw”), and the like have long been associated with the popular concept of dyslexia. Research has not supported a direct relationship, however, a correlation does appear to exist at some level. Are such apparent problems the result of the inability to perceive the left to right orientation of written English or is it the skill to perceive meaning in either direction? Delos Smith, for instance, writes backwards, I maintain that this is because he chooses to do so, not because he can’t write from left to right.Dr. Orton described a person with “strephosymbolia” among other traits as having “an unusual skill in mirror writing” (emphasis added, Orton, 1929, p 121). One can interpret that comment as meaning that such a person had the choice and, therefore, some confusion “between dextrad and sinistrad orientation of letters…” Id.Mirror writing is an example of the choices available to an individual who can perceive meaning from symbols presented in unorthodox spatial orientations. Such a person would have to possess well-developed visual-spatial skills.

  5. Nonverbal Learning Disabilities (NLD):
    It is repeatedly reported that the phenotype commonly referred to as a nonverbal learning disability (NLD) often includes good, even excellent, reading skills. It is also interesting to note that, in spite of almost precocious reading skills, many of these children are identified as being at risk for reading failure in pre-kindergarten screen tests.”The principal neuropsychological asset of children who exhibit the NLD syndrome is their capacity to deal with information delivered through the auditory modality.” (Rourke, 1995 p. 8).The observation that NLD children often experience “a discernible delay in the acquisition of speech” (Rourke, 1995, p.8) would, on the surface, appear inconsistent with the hypothesis being presented herein. However, as Foss (1991) stated most parsimoniously “Our first, most basic communications are nonverbal.” Once the early developmental reliance on nonverbal communications is replaced by a more verbal environment such “children progress through the various stages of speech and language development at what seems to be an above – normal rate of speed” (Rourke, 1995, p 8).The NLD child is not necessarily a good reader as a result of better than average skill in phonological processing, but rather is a good reader as the result of having relatively poor visual-spatial skills that cause such a child to rely on and develop a large repertoire of spoken word to meaning associations. Ostensibly, the NLD child’s ability to read is enhanced due to a relative weakness in visual-spatial skills as compared to phonological processing skills and a dyslexic child’s ability to read is diminished due to a relative strength in visual-spatial skills as compared to phonological processing skills. Individuals logically tend to practice and hone the modality that moves them most efficiently from stimulus to meaning.

     

    Interestingly, both the NLD and the dyslexic child appear to experience delays in the acquisition of speech. Could it be, as previously speculated, that the NLD child experiences delay in very early speech development due to its very close association to the earlier nonverbal communications? The opposite may be true for the dyslexic child that is so adept at nonverbal communications that early speech is almost unnecessary. The NLD child appearing cold, aloof, self-absorbed; while the dyslexic child is cuddly and empathetic (you can read in his eyes when he is hungry, wants to be changed or picked up). One has difficulty making the transition from nonverbal to verbal because of a lack of nonverbal knowledge; the other has difficulty with the same transition because of an over-reliance on nonverbal communications. It doesn’t matter which side is heavier, it is the lack of balance that causes the delay.

    The Brain Symmetry, Cognitive Profile, Rapid Naming, and Mirror Writing addressed above all appear to support the existence of a relative superiority of visual-spatial skills as compared to phonological skills as a result of intrinsic neurobiological factors. With the discussion of the NLD child one would speculate that environmental influences as well as neurobiological factors could play a role. For instance, the NLD child may be neurobiologically deficient with regard to visual-spatial skills, but it is such a child’s exposure to verbal language without distracting nonverbal cues that most probably enhances the rate at which reading skill is acquired. In other words, the NLD child does not necessarily have neurobiologically superior phonological processing skills. A more clearly, nonneurobiological, environmentally mediated distribution of relative strengths and weaknesses may be the so-called “race effect.”

  6. Race & Socioeconomic Status:
    Any condition that would result in relative over-reliance on nonverbal cues in oral discourse would likely result in an impoverished store of the spoken word to meaning associations. For instance, wouldn’t a socio-cultural milieu that relies to a greater extent on nonverbal cues and idiosyncratic syntax in spoken discourse be at a disadvantage in learning to read as compared to a socio-cultural milieu that relies less heavily on nonverbal cues and uses a more standard syntax?The finding that low socioeconomic status is not a predictor of poor reading skills, in and of itself, might support this approach. For instance:

     

    1. The fact that an individual is of low socioeconomic status is not a valid predictor of reading failure.

    2. The fact that an individual and the school are in a community with a low socioeconomic status is a robust predictor of reading failure.

    3. Conclusion – it is something within the community dynamics that account for the correlation of socioeconomic status and reading.

    4. The “street language,” dialect or oral discourse in many communities of low socioeconomic status is limited in spoken word vocabulary, has an idiosyncratic syntax, and is rich in nonverbal cues. The corollary would also be true. A child of a family of low socioeconomic status brought up in a community of higher socioeconomic status is exposed to oral discourse richer in vocabulary, less idiosyncratic syntax, and less reliance on nonverbal cues.

    In referring to the Wood et als. (1991) attempt to “understand the race effect” Reid Lyon indicated that a number of factors were assessed “including parental marital status, parental education, parental status as a welfare recipient, socioeconomic status, the number of books in the home and occupational status.” “The presence of any or all of these demographic variables in the prediction equation ëdid not remove the race effect from its potency as an independent predictor of third-grade reading’ (Wood et als., 1991, p. 9).” Wood’s findings also indicated that race was not an “influential variable” at the first-grade level. Wood’s study found that the race effect becomes more severe with age and speculated that “the nature of the dialect of the African American children may interact negatively with any reading approach that does not explicitly emphasize specific sound-symbol relationships.” (All from Reids Chapter in LD/Lifelong Issues at p. 10, 11.) I might simplify this speculation by suggesting that any dialect that relies on idiosyncratic syntax and nonverbal discourse to the detriment of developing a spoken vocabulary interacts negatively with any reading approach. The impact of such a variable is consistent with the finding that it becomes more salient with age.

    What am I saying? Well for one thing, it is not the relationship of socioeconomic status and IQ that determines reading success. Secondly, it is not a problem in phonological processing that accounts for reading failure related to socioeconomic status. Thirdly, it is the combination of idiosyncratic syntax, a learned over-reliance on context and nonverbal cues, and a concomitantly impoverished repertoire of spoken word to meaning associations that accounts for reading failure related to socioeconomic status or the so-called “race effect.”

    If we teach individuals to decode from a written language to spoken language without the ability to decode such spoken language to meaning, they will be seen as being unable to comprehend written text. The problem is not the written text but the spoken text sans the syntax and vocabulary standard to the written text. Such a person is “a stranger in his own language” (cite?). In her comments on “Contextual Facilitation and Comprehension” (Adams, 1990, p140), Marilyn Adams describes text comprehension as a “hierarchically layered process” requiring the retrieval of the meaning of each word encountered, the recognition of syntactic boundaries, and, as difficulty increases, the recognition of “more subtle junctures.” It would be logical to assume that a dialect common to a community with a vocabulary and syntax that does not correlate to standard written English will result in (a paraphrase of Adams, 1990, p 141) “readers try[ing] to recode at a syntactically inappropriate point in the sentence [where] they find themselves in the position of trying to interpret a syntactically anomalous set of words. In this case, too, comprehension must suffer.”

    If we don’t speak the language, we are going to have difficulty reading the written language that is intended to map to the spoken language. If our oral discourse utilizes idiosyncratic grammar, vocabulary, and syntax or if it merely over relies on nonverbal cues, we will still have trouble mapping written language to a meaningful spoken language.

STATISTICAL DISTRIBUTION:

An individual with phonological processing skills that would normally place him above the demarcation line to be classified a deficient reader may be pushed below the line as a result of the synergistic effect of having relatively superior visual-spatial skills. The result would be that persons identified as deficient readers would, statistically, have below average phonological processing skills and above average visual-spatial skills. In other words, if all individuals in the general population with a relative differential between visual-spatial skills and phonological processing skills, with visual-spatial skills being a relative strength, had more difficulty reading than that which would be predicted by phonological processing skills alone, there would be a shift into the deficient reading range of those whose phonological processing skills alone would not predict them to be deficient readers. A counter shift would also be likely, i.e., those with phonological processing skills with relatively weaker visual-spatial skills would shift in the direction of better reading ability than would otherwise be predicted by phonological processing skills alone.

MATTHEW EFFECT:

Keith Stanovich’s proposition that “the rich get richer and the poor get poorer” generally infers that the rich and the poor proceed relatively independent of each other. The spin that I propose is that the poor get increasingly poor because the rich get increasingly rich in an environment where there are finite resources. For instance, if the attention and vigilance that is available to an individual is dedicated to interpreting communications in terms of nonverbal cues, such dedication works to the detriment of developing skill in interpreting the literal meaning of spoken words. The better the individual is at interpreting nonverbal stimulus, the more the individual practices and develops that skill while neglecting the development of those skills that are necessary to interpret the meaning of the spoken word that is not enmeshed in a context full of clues to meaning. Verbal discourse involves words in context. In a sense then, the rich (nonverbal skills) get richer, and the poor, (the phonological processing of spoken words), gets poorer. As a result, such an individual would have an unexpectedly anemic repertoire of meaningful speech sounds in long-term memory.

EXPRESSIVE WRITTEN LANGUAGE:

Problems with expressive written language are faced by both Dyslexics and those with nonverbal deficits (otherwise exhibiting excellent decoding skills). Why? How does this knowledge fit with the construct I am trying to develop? Perhaps this phenomenon may be explained in this way: Dyslexics don’t have the words to use and nonverbal individuals don’t know how to use the words they have.

Given facility with words, the Dyslexic would have the relative ability to employ the “context processor” to put such words together to parsimoniously convey meaning and understanding through their harmonious arrangement. The Nonverbal individual has a facility with words but a relative inability to order them in such a way as to provide a depth of understanding using syntax to develop context.

[Note: Is there a way to test syntactical ability without using words? Also, if understanding is derived from context, syntax, and nonverbal cues, how does this affect our interpretation of psychological projections that rely on language (written and oral) to stimulate a response? Should defendants in court be given a language evaluation before taking the stand? Might they require an interpreter if they do take the stand?]

DISCUSSION:

For the sake of this discussion, I am viewing the road from reading to comprehension as series of correspondences and associations. In other words, we correspond symbols to sound – then correspond sounds to spoken words – then use our “context processor” (Adams, 1991) to help associate spoken words with meaning. The individual who has developed a facility with nonverbal communications at the expense of becoming fluent in the literal interpretation of spoken words can therefore be taught the symbol to sound correspondence necessary to translate the written word into the spoken word, however, this individual would continue to have an unexpected and surprising difficulty in comprehension as a result of his lack of fluency in associating the spoken word to meaning. Such individual’s oral discourse relies heavily on the nonverbal cues that are not embedded in the symbol to sound to meaning correspondences required for the comprehension of written language.

Therefore, it can be postulated that the dyslexic with good visual-spatial skills may be expected to be more resistant to treatment than his IQ and phonological skills alone might predict. Even if such a person is taught to decode with relative fluency, he may continue to experience significant problems with comprehension. Also, persons with apparently adequate phonological processing skills may be poor readers due to a relative visual-spatial strength.

I don’t believe that there is anything in this paper that is unique, novel, or hasn’t been addressed many times before. However, I do believe that current research into treatment methods may overlook the salience of relatively strong visual spatial skills or a mode of oral discourse that over relies on nonverbal cues and idiosyncratic syntax and grammar. In order to be good in all of the aspects of written language, ones mode of oral discourse must be in harmony with the written language. One cannot efficiently map a written language to a spoken language if they do not share similar topography.