الفهرس 
Introduction and RationaleOnly 14 pages are availabe for public view
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Abstract
Learning disabilities (LD) refer to a group of heterogeneous disorders which may affect the acquisition, organization, retention, understanding or use of verbal or nonverbal information (Sahoo et al., 2015). In Egypt 16.6% of primary school students are at risk for LD with male to female ratio 2:1 (Ismail et al., 2019).
Dyslexia is the most common LD, accounting for at least 80% of all LDs (Kohli et al., 2018). It is characterized by problems with accurate or fluent word recognition, poor decoding, and poor spelling abilities, despite adequate intelligence, motivation, and educational opportunities.
Central auditory processing (CAPD) is characterized by poor perception of speech and non-speech sounds. Individuals with APD may present by listening difficulties, difficulty in hearing& understanding speech in noise, difficulties with sound localization, poor attention and/or memory. They may have impaired speech, language, literacy and academic performance (BSA, 2018).
Primitive reflexes are complex, automatic movement patterns that commence as early as the twenty-fifth week of gestation, are fully present at birth in term infants. At the age of three years the primitive reflexes should be fully inhibited and no longer interfere with movements. Replacement reflexes, called postural reflexes, emerge (Fong et al., 2012). Postural reflexes are more mature patterns of response that control balance, coordination and sensory motor development.
Retained primitive reflexes coined to developmental delay. The degree of maturity of the CNS can be determined by assessment of presence or absence of primitive reflexes (Marovic et al., 2015).
As CAPD and dyslexia are considered as a neurodevelopmental disorders, accordingly investigate other aspects linked to neuromotor maturation will be of clinical value. The purpose of this study was to assess balance functions and primitive reflexes in learning disabled children.
The present study was conducted on 70 children divided into two groups:
Control group consists of 20 normal children their age ranged from 6 6/12 to 9 years old which is further subdivided into younger subgroup age ranged 6.5 to 8 years mean age was (7.41±0.6) and older subgroup aged from 8 to 9 years mean age was (8.9±0.2).
Study group consists of 50 children with learning disability divided into two subgroups:
• Combined group: 40 dyslexic patients with comorbid central auditory processing disorder. Age ranged from 6 6/12 to 9 years. Divided into younger subgroup age ranged 6.5 to 8 years mean age was (7.1±0.6) and older subgroup aged from 8 to 9 years mean age was (8.8±0.2).
• Isolated CAPD group: 10 patients with central auditory processing disorder with normal reading abilities. Age ranged from 8 to 9 years; mean age was (8.9±0.2). The study groups and control group are age and gender matched.
All cases underwent the following:
1. Full history taking.
2. Balance functions tests evaluation includes:
• Office test including Romberg, unilateral stance, Fukuda stepping test & modified Clinical Test for Sensory Interaction and Balance (mCTSIB).
• Oclumotor test using video goggles (random saccade& smooth pursuit test).
• Computerized Dynamic posturography (sensory organization test) (SOT).
3. Cerebellar function test include:
Tandem gait, pronation/supination test, finger to nose test.
4. Psychophysical central test battery.
• Speech in noise test
• Dichotic digits test
• Pitch pattern sequence test
• Auditory fusion test
• Memory test (recognition memory, memory for content& memory for sequence).
• Auditory continuous performance test.
5. Examination for presence of Primitive reflexes (Goddard, 1996):
• Asymmetrical tonic neck reflex.
• Symmetrical tonic neck reflex.
• Grasp reflex.
• Tonic Labyrinthine reflex
• Landau reflex.
6. Examination for absence of righting reflexes (Goddard, 1996):
• Head righting reflex (oclumotor & labyrinthine).
The study showed that all children with developmental dyslexia have comorbid auditory processing deficits. Poor memory for content and sequence was the most affected ability in both study groups.
Dyslexics were less stable than control group during balancing on one leg eye opened &closed conditions and in condition 4,5,6, composite score and visual& vestibular ratio in SOT. Suggesting that motor performance of dyslexic individuals would be affected by their difficulty to transform multiple sensory cues available into relevant information to perform purposeful task in an automatic manner. This is probably due to delay maturation of integrated balance neural networks. That’s in line with the delayed neural commitment theory of dyslexia (Nicolson and Fawcett, 2019).
Impaired balance functions in learning disabled children have several implications in their daily life activities. Those children may have difficulties to keep their balance in situations in which visual and / or somatosensory is altered or deficient so balance functions of those children should be taken in consideration during the management plane.
Isolated CAPD group showed significant impairment of balance control compared to control group in unilateral leg stance eye closed condition only. This is probably due to delayed maturation of their nervous system (vestibule spinal reflex).
There was no significant difference between both study groups and control groups as regards cerebellar function tests and oclumotor testing. Performing more challenging tasks may elicit abnormalities in those children.
Children with CAPD and/or dyslexia have a high percentage of retained primitive reflexes. According to the data 67.5% of the combined group& 70% of the CAPD group have at least one retained primitive reflex and /or underdeveloped HRR.
The STNR& Grasp reflexes were the most prevalent retained reflexes in the study groups. Twenty percent of combined group and half of the CAPD group had underdeveloped HRR.
Correlation studies showed that retained primitive reflexes were significantly negatively correlated with decoding & memory tests scores. ATNR was correlated with increase non -sense passage reading duration. TLR retention significantly correlated with tandem gait test abnormality also underdeveloped HHR was correlated with postural instability in unilateral leg stance.
To conclude, the results of the current study emphasized that learning disabilities particularly dyslexia is considered as a neurodevelopmental disorders that goes beyond reading difficulties. It includes a delay in neuromotor maturation. This neuromotor maturation delay in turn led to impaired balance functions and CAP disorders in those children
We can speculate that delayed maturation is one of the reasons of compromised cognitive, linguistic and motor abilities of dyslexic children.