Development and Standardization of Low-Verbal Material for Assessment of Central Auditory Processing in Arabic Language

Abstract The early years of life represent a critical period with rapid growth of interrelated functioning of cognitive, sensory and socio-emotional abilities. Cognitive abilities and central auditory processing work together especially as everyday listening conditions become increasingly strenuous. Current available tests that assess cognitive and auditory processing abilities in Arabic language utilize verbal load that is non-convenient to most young, cochlear-implanted children and children with delayed language development. Consequently, assessment of these children relies in many instances on the use of non-verbal material. In the current work, we developed a child-friendly computer-based program of low-verbal quality to assess auditory working memory, selective auditory attention, temporal processing and interhemispheric transfer of auditory information. The scores of 90 typically developing Egyptian children (2.3 to 5 yrs old) were obtained. Here we present the results of auditory working memory. Our results demonstrate clear maturation effect in auditory working memory and hold premises to assess and track these abilities in cochlear-implanted and linguisticallyimpaired children with language age as young as 2 yrs. Aims This study aimed to construct and standardize a low verbal test to track the development of auditory working memory in Egyptian preschoolers (2-5 years) using child friendly computer-based program. Material and Methods Mono-syllabic and bi-syllabic nouns of early receptive vocabulary of children aged two to five years (in the Colloquial Egyptian Arabic dialect) were used. All test items (target and distracter items) were reviewed by an expert phoniatrician. Material recording was performed at specialized studio in Cairo by female speaker. Recorded material was digitally averaged then calibrated using Brüel & KjærTM sound level meter. Test items were arranged into trials with increasing number of test items with level progression, using 1 sec. inter-stimulus interval (ISI). A software (game) was developed on a tablet. The game plays the audio of test trials, after 1 second, picture cards are displayed. The pictures of test items and distractor items were arranged into multiple choice format.The software gives positive reinforcement and alerting sound following correct and incorrect responses respectively. Following oral consent by parent/caregiver, 90 normal developing Egyptian preschoolers were assessed. They were recruited from relatives of workers of audiology unit at Ain Shams University and kids attending national nurseries with the following inclusion criteria: No history of hearing complaints, delayed language development, motor disability, neurological disorders, pervasive developmental disorders, behavioral problems nor delayed language development. Normal hearing sensitivity and normal middle ear functions, Arabic as mother tongue, no formal musical training, normal speech and language development evidenced by history and mPLS-4 language test, and average or above average intellectual ability (IQ) by Hiskey Nebraska of Learning Aptitude test or Vineland Social Maturity Scale. Testing was conducted in quiet furnished medium-sized rooms. Child was comfortably seated in kid’s chair and tablet was placed on table in front of him/her. Protective measures against covid-19 were taken. Final score of content for each child was obtained. Results and discussion The Shapiro Wilk test was used to assess parametric versus non-parametric distribution of children scores and showed high value of test coefficient (p < 0.05) indicating that children scores have non-parametric distribution (as commonly observed with ordinal data) (Table 1). Accordingly, data were presented as median and inter-quartile range (IQR).Median= 3, IQR = (3 – 4). Also, percentage of children in each level revealed that most children reached level 3 with no floor nor ceiling effects (Table 2 & Figure 1). Spearman Correlation between newly developed test, age, language, and IQ revealed a positive (strong) linear correlation with age only (p < 0.001) and no correlation to language nor IQ (Table 3 & Figure 2). Test-retest reliability using Mann -Whitney test (2 weeks interval) showed good test-retest reliability (t=-1.000 and 0.000, p = 0.331 and 1.000) for Memory (Mono-syllabic) and Memory (bisyllabic) respectively. To the authors’ best knowledge, no similar methodology was performed in the literature, thus we resort to studies with different methodologies to compare our results. Using a non-word repetition (NWR) task, Radeborg et al. (2006) observed the improvement of children performance with age from the age of 4 till 6 (mean= 4.4, 4.8, 5.1 correct word repetition for each age strata with 2 syllable nonwords arranged in sequences of six Swedish nonwords). Similarly, Lázaro et al. (2017) also used a non-word repetition task but they required children to repeat the nonwords after listening to the stimuli twice. They reported a significant increase in percentage of correctly repeated non-words from ages 4-6. Roman et al.(2014) used The Missing Scan Task (MST) in children from 3-6 yrs of age and reported increasing number of correct responses (means=4 for 3-4 yrs old that increased by roughly 1 for each 1 year age strata). Results of the present research go in agreement with the above studies. This improvement in verbal working memory could be attributed to the increased grey matter thickness in frontal, temporal lobes and hippocampal regions that takes place throughout childhood till adolescence. However, the linkages between changes in brain morphology and memory abilities are still not well understood (Schneider & Ornstei, 2018). Conclusions A tablet game was successfully developed to track the maturation of auditory working memory in Egyptian preschoolers. The low verbal load, closed-set, attractive properties of the test hold premises for future assessment of children with language expressive deficits including those with hearing impairment and delayed language development in addition to children with ADHD.