Linguistic, Literacy, Prosodic & Pragmatic Characteristics of children with Dyslexia

Linguistic, Literacy, Prosodic & Pragmatic Characteristics of children with Dyslexia.

Co morbidity:  The conditions that most commonly linked to Dyslexia are:

*          Dysphasia: A speech and language delay/deficient

*          Dyspraxia: A physical coordination disorder that comes from an immaturity in the way the brain processes information, resulting in messages not being properly transmitted. Flory, 2003

*          Attention deficit disorder with or without Hyperactivity: The co occurrence is reported to be 15 to 40%. Rucklidge & Tannock, 2002

*          Dyscalculia: Specific learning disability in mathematics is a feature of Dyslexia. Milton, 2001.

Cited in Scott, R.M & Snowling, M (2004). Dyslexia and Counselling. Whurr publications.

Neurobiological evidences:

☻   In post mortem studies of cases of developmental Dyslexia 5 cases showed evidence of small areas of cortical dysgenesis (Microdysgenesis) including ectopias (small nests of abnormally placed neurons) and

Dysplasia (focally distorted cortical lamination). Livingstone, 1993 & Galaburda, 1999.

☻   Another set of examination on thalamic structures, specifically MGN & LGN of auditory pathway revealed magnocellular layers of LGN more disorganised in Dyslexics. Livingstone et al, 1991.These differences were related to the auditory temporal processing abnormalities in language impaired children.

☻ According to Jenner et al, 1999 neuronal symmetry in primary visual cortex is associated with abnormality in circuits involved in reading.

☻ Galaburda et al, 1994 hypothesized that Dyslexia is an outcome of anamolous neural development, which might derive from brain injury during the prenatal stage & the chemical environment and the maturation rate of brain areas are assumed to interact.

☻  In a study of children with dyslexia and non impaired, they demonstrated significantly greater activation than do dyslexics in predominantly left hemisphere sites (including the inferior frontal, superior temporal, parieto temporal and middle temporal- occipital gyri).Shaywitz,2005.

☻  A number of interrelated neural networks are used in reading, at least 2 in posterior brain region and as well distinct & related network in anterior region.

☻  The anterior network in inferior frontal gyrus (Broca’s area) has long been associated with articulation and also serves an important function in silent reading and naming. (Fiez & Frackowiak et al.,2004)

☻  The 2 posterior regions appear to parallel the 2 systems proposed by Logan (1988, 1997) as critical in development of skilled, automatic reading.

☻  Research has converged to indicate that the second posterior network , localized to a region termed the visual word-form area influences skilled fluent-reading.(Cohen, Sigman, Nakamura et al.,2005)

☻ They have suggested a systematic sensitivity to coding within the left occipito temporal region, with most posterior regions coding for letters and letter fragments and more anterior regions coding for bigrams and words.

☻  Reduced activation in the occipito-temporal region may underlie the reading and naming deficits observed in developmental dyslexia (McCrory, Firth, Price, 2005)

☻ Although they exhibit a dysfunction in posterior reading systems, they appear to develop compensatory systems involving areas around the inferior frontal gyrus in both hemispheres as well as the right hemisphere homologue of the left occipitotemporal word form area. B.Shaywitz et al.,2005

☻ These findings support to the idea that systems involved in all levels of the reading process, from processing sensory input to higher-level analysis of phonological information, may be affected in Dyslexia.

Cited in Breznitz, Z (2008).Brain Research & Language. NewYork; Buisness media

Language characteristics:

The best studied characteristic of dyslexics is deficits in phonological processing and in the processes underlying naming speed (Wolf et al., 1999, 2002).

Studies suggest that children with Reading disability exhibit a range of subtle deficits in their spoken language, including reduced grammatical complexity and a variety of problems with phonology. (Snowling, Gallagher, 2003)

Word finding deficits:

        Majority of children with RD have word finding deficits defined as a problem in generating the specific word evoked by any given situation also called “ subtle Dysnomia”.(Wolf & Obregon, 1992).

As a result of this many children manifest a variety of secondary behaviors like hesitations, reformulations, stereotypic starters, repetitions, circumlocutions and production of fillers, use of nonspecific words & substitutions in spontaneous conversations and narratives.(Simon & German,1991, Dockrell et al, 1998 )

Findings suggest that word finding difficulties in dyslexia may involve deficient mapping of or an access to phonological representations & that a selective phonological deficit is associated with and perhaps the cause of naming difficulties in children with Dyslexia.(Mc Gregory, 1994: Swan & Goswami,1997)

Cited in Faust, M & Dimitrovsky, L (2003). Naming Deficits in children with Dyslexia. Journal of learning disabilities. Vol.36, pg.no:202-215.

Visual processing Deficits:

Difficulties in:

•      Discrimination of size and form of letters, numbers.

•      Visual analysis of letter forms and extraction of invariant features.

•       Visual discrimination between similar forms in written system leads to Reversals in lower case alphabets e.g. b/d, p/q, h, u/n, f/t, c/e, m/w letter order e.g. saw/was which have a high degree of visual similarity.

•      Visual spatial scanning ability to track print from left to right & top to bottom  i.e. Directional confusion in whatever is appropriate for writing system.

•       Recognizing letter characteristics

•       Serial visual memory for patterns of individual letters, of letter strings (e.g. ‘ph’, ‘ght’ or ‘th’, ‘ing’) that make up orthographic (spelling) patterns of language and of whole words both to recognize them for reading and to recall or “ revisualize” them for writing.

•      Visual linguistic integration to associate letters and words in with sounds and word meaning.

                                                                                                             Willows, M.D (1991)

*     There is evidence of an abnormality called “visible persistence” in the early stages of processing of transient visual stimuli in individuals with Dyslexia.

*           This perceptual deficit could result in impaired visual memory, especially for items in sequences, and could interfere with reading by generating overlapping or superimposing images of letters.(Farmer & Eden et al,1995)

Visual perceptual Deficits:

Because of difficulty in visual perception, disabled readers seem to confuse similar looking letters and words in their reading and writing. Techniques used to examine are:

*  Temporal Integration: It is an index of visual persistence of a stimulus after its termination. Examiner assesses whether the stimuli presented in very close temporal sequence have been perceived as two separate stimuli or as a single one.

*  Backward masking effect: When the onset of one stimulus target is followed immediately by onset of another visual stimulus (masking stimuli), the second stimulus interferes with the processing of first. It provides a measure of rate of information pick up in the initial stages of information processing.

Results from the studies above indicate that disabled readers do not process visual as quickly as normal readers of similar age.

Some of the major components of visual perception in which dyslexics find difficulty are summarized:

Form perception

Figure ground discrimination

Spatial relationships

Visual motor integration

Visual Memory Processes:

Tasks used are:

*        Visual recognition memory: used to recognize unfamiliar visual stimuli that resemble word contours or word shapes. Findings showed that reading disabled children were less accurate and slower in their visual recognition performance.

*        Reproduction from visual memory: In learning to read and write, child must attend to and remember visual in the symbols to recognize them for reading and reproduce them for writing. Disabled and normal readers may differ in drawing unfamiliar visual patterns from memory task.

*        Visual Paired associate learning: no differences in disabled and normal readers.

*        Serial learning of visual designs: No differences.

Thus visual perceptual and visual memory deficits may be implicated in reading disabilities.

Language deficits affecting literacy

Primary Deficits in

a)         Decoding the print automatically due to deficits in phonological processing and phonological awareness. (Torgesen, Wagner & Rashotte, 1994). The several possible levels or components to this code breaking they are: -

  -  Unable to match graphemes and phonemes.

  -  Difficulty in visual memory skills to remember orthographic configurations.

- Unable to retrieve the sound symbol & orthographic representations quickly and automatically.

             Deficits in any of above areas will result in slow, halt reading, and so much of working memory devoted decoding/ retrieval, few resources are left for comprehension.

b)        The low level of comprehension exhibited by many poor readers is consistent with their other verbal skills(part of verbal/semantic deficit) (Stothard & Hulme,1996)

c)         At micro structure level (involving semantics, syntax, and cohesion): They fail to comprehend words and concepts; they have difficulty tracking cohesive elements.

d)        Deficits in knowledge of word meaning (semantics): They may have difficulty with multiple meaning words, verbs, adjectives, adverbs and prepositions. Poor interpretation of alternative meanings of sentences with dual meaning words. E.g. “chickens ready to eat” ambiguous sentences.

e)         Deficits in knowledge of word formation rules (morphology):They may ignore hard to hear parts of words, such as word endings, unstressed words, phrases and parts of clauses, when listening to and interpreting spoken language. They focus more on stress or high information content.

f)         The word endings used for inflection and derivation may cause special problems because of their short duration and low intensity in running speech. The major difficulties experienced in acquiring the phonological conditioning rules for the –ez and –ed variations of inflectional word endings (noun plural ending in /∂z/, and past tense of regular verb endings in /∂d/.

g)        Deficits in sentence formation rules (Syntax): These children will have trouble learning sentence transformations like the passive in which the usual order of presentation of object is altered, interrupted or reversed. These delays are reflected in both interpreting spoken language and formulating sentences.

h)    These syntactic deficits persist into adolescence and adulthood if they remain untreated. (Wiig & Semel, 1980). They have difficulty in understanding, remembering and using structurally complex sentences e.g. Producing wh- question sentences with demonstrative pronouns( this, that these, those) passive sentences , sentences with indirect object transformation and sentences with embedded clauses e.g. the burgler that the police found escaped easily.

i)      There greatest difficulties occur when sentences are syntactically well formed but violate word selection rules, as in “colorless green ideas sleep furiously” or when they contained a random word string, “ not in a tree to the lake with”. On a sentence formulation task, which required them to use a given word in a sentence, they produced:

-          Agrammatical and incomplete sentences.

-          Simple, active, affirmative and declarative sentences.

-          Agent action object sequence which is typical for younger 7-8yrs old children.

They did not use sentence transformations used by academic achievers of their age.

j)          Interpreting and integrating the syntactic and semantic information from different parts of the text and using complex syntactic structures involving dependent clauses and modifiers, such as adjectives, adverbs and prepositional and participial phrases.

k)        They fail to recognize that different types of text and fail to integrate information across one or more texts to develop overall gist of text. (Westby, Clauser, 1999). Making relevant inferences to what is “read between the lines”.

l)          Using Metacognitive skills to notice inconsistencies in texts, recognize when they do not comprehend, and remedy the comprehension failure i.e., they fail to monitor their comprehension.

m)      Poor comprehenders exhibit poorer use of linguistic devices that foster cohesion, such as anaphora and causal relationships.

n)        When asked to retell stories that had limited use of temporal and causal connectives 25% of the less skilled comprehenders added any connectives but none of these were causal.

o)        They used ambiguous pronouns and they were more likely to tell stories from pictures in present rather than past.

(Yuill & Oakhill, 1991)

Cited in Butler, K.G & Silliman, E.R (2002). Speaking, reading and writing in children with language learning disability, London, Lawrence associate publi

Language and Literacy characteristics:

·         These children may be slower in reaching the developmental milestones for using words and sentences i.e. language delay.

·         Vocabularies may be more limited than age, intelligence and background experiences indicate.

·         Early phonological difficulties include not attending to sounds of words (trouble learning nursery rhymes & difficulty in generating rhymes and matching initial sounds.

·         Confusing words that sound alike, mispronouncing words. Confusing small words such as at for to, said for and, does for goes. Longer than more I graders they will continue to reverse or rotate letters and numbers when they write.

·          More difficulty decoding nonsense words than content words. Sometimes mix up the order of syllables within words and produce spoonerisms.

·         Number difficulty in Dyslexics are of 2 forms:

-          True Dyscalculia where children have profound difficulty with number concepts.

-          Common type in which child may understand the mathematics and be able to solve the question but may use the wrong operator or record digits inaccurately. Clayton, 2001.

·         Dyslexic children may laboriously learn how to read words accurately but do not become fast or automatic readers. Difficulties become apparent when they are asked to read aloud in class where mispronunciations, omissions of words or conversely inserting words that are not on page, reading with lack of prosody, frequent pauses, hesitations or loss of place are noted.   

·         When they are learning to do cursive writing they find it hard to remember the motor patterns of letters, messy handwriting, and poor spelling result in difficulty in note-taking in class. (Firth & Snowling, 2000, Shaywitz, 2003)

·         Self-esteem is frequently affected, particularly if the disorder has gone undetected for a long period of time. (S.Shaywitz, 2003)

·         Directional confusion and sequencing difficulties are a central part of dyslexic problem and intimately linked with their magnocellular deficit. Continue to confuse right and left directions and the orientation of body in the space.

·         Davis (1997) a dyslexic writing on dyslexia, argues that confusion is an essential part of dyslexic way of relating to the outside world which is called as “process of positive disorientation”. This distorted perception is used to shift their views of events.

·         Have trouble relating sound to written symbols and blending these sounds into known words. Written expression will be simple even though they may have complex ideas to express.

Cited in Silver, A.A., & Hagin, R.A (2002). Disorders of Learning in Childhood. II edn   New York. John willey. 301. Sally Shaywitz, Jeffrey R. Gruen. Hand book of Child language disorders.

Cognitive-Linguistic Deficits:

ó     In short term memory when retrieving verbal items. Gathercole and Pickering, 2001. Very poor working memory capacities of dyslexics largely affect their ability to process and sort different, incoming categories of information simultaneously.

ó     Dyslexics have problems in remembering dates, numbers strings and information where they left keys, they rely more on long term memory, which is based more on association, context and understanding.

ó     Yuill & Oakhill, 1991 investigated child’s ability to give empirical and deductive explanations. Good comprehenders and poor comprehenders performed similarly in giving empirical explanations.

ó     But poor comprehenders were significantly poor on deductive explanations because they tended to interpret deductive as empirical.  Consequently when asked to complete a sentence such as “we can tell that Mary has cold because….. They are likely to respond with because she got soaked, instead of because she is sneezing”.

ó     Such a misinterpretation would result in inadequate mental models for texts that code deductive relationships and suggest that poor comprehenders would be more likely to give pragmatic inferences when logical inferences are required.

ó     They exhibit greater difficulty in pronominal references, particularly when the pronoun and its referent are not adjacent to each other.

ó     Causal relationships are also central component for mental models for both narratives and expository text. Poor comprehenders are less likely to draw causal inferences when the causal relationships are not marked linguistically.

e.g., Mukesh wanted a new bike. He worked as a waiter at pizza hut and he often had to work late at the night. So he had trouble staying awake in the class.

ó     Poor comprehenders will have difficulty in understanding if the passage is written as “Mukesh wanted a new bike so he took a job as a waiter pizza hut to earn money. Mukesh had trouble staying awake in the class because he often had work late at pizza hut”.

ó     Grant (2001) believes that multiple cognitive deficits of Dyslexics enable them to arrive at creative solutions to problems. Weak working memory and slow speed of visual processing associated with high levels of abstract verbal and visual reasoning ability.

ó     This in turn is linked to the capacity for problem solving. Weak working memory affects problem solving because ideas slip in and out of conscious thought in random manner. As a consequence, ideas can enter almost randomly and as they do so other ideas disappear from consciousness almost.

ó     This results in a transient and chaotic experience almost like an ongoing “brain storming session”. This results in unusual juxtapositions with consequence that the solutions are more likely.

ó     Dyslexic’s difficulty with semantic memory deficit may stem the use of analogies and encourage novel strategies and solutions.

Behavioural characteristics of children with Dyslexia:

Ø  Academic underachievement and problem behaviors frequently co-occur.(Trout et al, 2003,Reid et al,2004). The link between behavioural problems and reading difficulties is well established. (Greenbaum et al, 1996) found that the percentage of children with emotional and behavioural disorders (EBD) reading below grade Level increased from 54% to 85% across the studies 7yrs span.

Ø  Nelson et al, 2004 reported that 83% of their study sample of children with EBD scored below the norm group on standardized measure of reading skill.

•         One of four causal models explains this co-occurrence.(Spira & Fischel, 2005)

     - First, it may be the common cause variables e.g. poor attention leads to problem in both reading and behaviour.

     - Second may be reading problems may trigger frustration, agitation, avoidance and withdrawal from learning tasks like behavioural problems. (Fleming et al, 2004)

     - Third may be that behavioural problems lead to reading problems. Off-task and disruptive behaviours might decrease attending to instruction and activities, there by worsening a child’s school performance. Reid et al, 1999

     - Fourth it may be that reading and behavioural problems cause each other. Both factors might be reciprocally causative over time, leading to a negative feedback cycle of increasing problem behaviours, school disengagement and academic failure. (McGee et al, 1986)

Problem behaviours include poor:

a)         Task engagement: attentiveness & task persistence, eagerness to learn, learning independence, flexibility (easily adapts to change in environment) and organisation.

b)        Self control - child’s ability to control his or her behaviour:  respecting the property rights of others, controlling temper, accepting a peer’s idea for group activities, responding appropriately to peer pressure.

c)         Interpersonal skills - child’s ability to initiate and maintain friendships:  get along with people who are different, comfort or help peers, express his or her feeling, ideas and opinions appropriately and show sensitivity to the feelings of others.

d)        Externalizing problem behaviours - acting out behaviours: arguing, fighting, and showing anger, acting impulsively, disturbing the classroom’s ongoing activity.

e)         Internalizing problem behaviours - Whether child appears anxious lonely or sad or has low self esteem.

Cited in Paul L.Morgan, George Farkas & Paula A. Tufis (2008). Are reading problems and behavioural Problems Risk Factors for each other? Journal of Learning disabilities, vol.41, pg.no:417-431

Prosodic characteristics in Dyslexic’s:

°   The potential role of prosody (suprasegmental phonology) in reading development has only recently been explored. One aspect of phonology that has recently received more attention is prosody: the phonological subsystem that encompasses the tempo, rhythm and stress of language.

°   It can be described as the melodic and rhythmic dimensions of speech and includes variations in pitch/fundamental frequency, loudness, duration, pauses, intonation, rate, stress and rhythm.

°   These dimensions are used to convey a number of different things, for example, lexical stress, focus, some aspects of meaning and emotion. Prosody therefore fulfils a variety of linguistic, pragmatic and affective/emotional functions, and so is essential for many different aspects of communication.

°   Wood and Terrell (1998) found that young poor readers are relatively insensitive to the suprasegmental (prosodic) cues of rhythm and stress at the phrasal level.

°   Goswami et al., 2002; Richardson, Thomson, Scott, & Goswami, 2004) found that poor readers are less sensitive to detecting amplitude envelope cues, representative of speech rhythm. They propose that this deficit may underlie the poor phonological representations and phonological awareness impairments characteristic of reading difficulties.

°   Prosody is a universal linguistic subsystem that performs many functions in all languages. Prosody interacts with, and adds value to, other language subsystems, such as syntax and semantics, facilitating understanding and providing scaffolding to children when acquiring language. For example, prosodic cues help segment the speech stream into phrases, words and syllables, inform syntactic structure, and emphasise salient information to facilitate understanding.

°   In English, the prosodic stress pattern of alternating strong and weak syllables provides a reliable and useful tool to separate words in speech, because strong syllables generally are assumed to mark the beginning of lexical words (such as nouns and verbs).

°   The retrieval of spoken words from the mental lexicon is facilitated by the word’s prosodic structure, providing a template or means for accessing lexical representations (Lindfield, Wingfield, & Goodglass, 1999)

°   The second universal property of prosody is the highlighting of prominent information (Bolinger, 1978). Prosody provides access to different meanings by focusing the listener’s attention on new or contrastive information and deaccentuating older or less relevant information (Warren, 1996)

°   Chunking by prosodic means also allows listeners to reduce their memory load by aiding the retention of an utterance until more abstract and complex syntactic and semantic processes occur (Speer, Crowder, & Thomas, 1993).

°   Furthermore, at the word level, prosodic cues are also necessary to differentiate between phonemically identical word strings in compound nouns (such as ‘blackbird’) and noun phrases or adjective and noun couplets (such as ‘black bird’) (Kitzen, 2001).

°   Prosody and syntax, therefore, interface in many constructions. For example, a sentence such as ‘she washed and dressed the baby’ has two syntactic structures, and therefore two meanings, which are disambiguated by prosody: [she washed] [and dressed the baby](that is, she washed herself, and dressed the baby) and [she washed and dressed the baby] (it was the baby that she both washed and dressed).

°   Moreover, given the bootstrapping role that prosody plays in early language acquisition (Morgan and Demuth, 1996, Christophe et al. 1997), impairment in prosody might conceivably create some difficulties in language acquisition. (Ramus et al. 1999).

Cited in R. Marshall, S. Harcourt-Brown, F. Ramus and H. K. J. van der Lely (2008). The link between prosody and language skills in children with specific language impairment (SLI) and/or dyslexia. International Journal of Language & Communication Disorders.

Pragmatic/ Social characteristics:

à   In appropriate social behaviour with authoritative persons/peers

à   Problems controlling impulses, reasoning, defining problems and evaluating consequence.

à   Difficulty in interpreting non verbal elements of social interaction.

à   Problems establishing relationship with staff and peers.

Dissertations done at Aiish:

i.            Logographic reading skills in children. Mythra Jagadish (1991)

ii.            A Tool for screening children with writing difficulties. Jayasree Shanbal (2003)

iii.            Reading Readiness Test in Kannada – its development and standardization. Devaki Devi (1978)

iv.            Test for writing of children in Hindi. Kiran.J (1994)

v.            Descriptive analysis of the sequential progression of English reading skills among Indian Children. Monika Loomba (1995)

vi.            Variables affecting rapid reading: an experimental study. Priya Kurian (1996)

vii.            Orthographic effects on naming speed and accuracy of reading. Roopa Rao (1994)

viii.            Reading acquisition in malyalam: A profile of the secondary grades. Seetha.L(2002)

ix.            Checklist for screening language based reading disabilities in children. Swaroopa (2001)

Thesis done at Aiish:

i.            A framework for testing Kannada reading on the Automaticity, rules of orthography and sequencing processing. G.Purusotham(1986)

ii.            Reading Acquisition profile in Kannada. K.S.Prema(1997)

iii.            Fine-Grained auditory discrimination on normal children and LD- Swapna.N(2004)

References:

•         Silver, A.A., & Hagin, R.A (2002). Disorders of Learning in Childhood. II edn, New York. John willey.

•         Sally Shaywitz, Jeffrey R. Gruen. Hand book of Child language disorders.

•         Scott, R., & Snowling, M (2004). Dyslexia & Counselling. London; Whurr publishers

•         Breznitz, Z (2008).Brain Research & Language. NewYork; Buisness media

•         Butler, K.G & Silliman, E.R (2002). Speaking, reading and writing in children with language learning disability, London, Lawrence associate publi

•         Shwartz, R.G (2009). Handbook of Child Language Disorders. NewYork; Psychology press.

•         Reutzel, D.R & Coole, R.B (1999). Balance reading strategies and practices.USA.

•      R. Marshall, S. Harcourt-Brown, F. Ramus and H. K. J. van der Lely (2008). The link between prosody and language skills in children with specific language impairment (SLI) and/or dyslexia. International Journal of Language & Communication Disorders.

•       Faust, M & Dimitrovsky, L (2003). Naming Deficits in children with Dyslexia. Journal of learning disabilities. Vol.36, pg.no:202-215.

•         Paul L.Morgan, George Farkas & Paula A. Tufis (2008). Are reading problems and behavioural Problems Risk Factors for each other? Journal of Learning disabilities, vol.41, pg.no:417-431

•         Karen Whalley and Julie Hansen (2002). The Role of Prosodic Sensitivity in Children’s Reading Development.  , Journal of Research in Reading.