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Psycholinguistic abilities in cochlear implant and hearing impaired children
Egyptian Journal of Ear, Nose, Throat and Allied Sciences (2014) 15, 29–35
Egyptian Society of Ear, Nose, Throat and Allied Sciences
Egyptian Journal of Ear, Nose, Throat and Allied Sciences www.ejentas.com
ORIGINAL ARTICLE
Psycholinguistic abilities in cochlear implant and hearing impaired children Hatem Ezzeldin Hassan a,b,*, Sally Taher Kheir Eldin c, Rasha Mohamed Al Kasaby d,e a
Otorhinolaryngology Department, Sohag University, Egypt King Fahd Hospital, Jeddah, Saudi Arabia c Otorhinolaryngology Department, Ain Shams University, Egypt d Otorhinolaryngology Department, Mansoura University, Egypt e Military Hospital, Riyadh, Saudi Arabia b
Received 20 September 2013; accepted 14 December 2013 Available online 17 January 2014
KEYWORDS Psycholinguistic; Cochlear implant; Language disorders; Hearing
Abstract Background: Many congenitally sensorineural hearing loss (SNHL) children and cochlear implant (CI) recipients develop near-normal language skills. However, there is a wide variation in individual outcomes following cochlear implantation, or using hearing aids. Some CI recipients or Hearing aids users never develop useable speech and oral language skills. The causes of this enormous variation in outcomes are only partly understood at the present time. So, the aim of this study was to assess the psycholinguistic skills in Arabic speaking children with either SNHL or CI in comparison to normal controls in order to estimate the nature and extent of any specific deficit in these children that could explain the different prognostic results of language intervention. Subjects and methods: Three groups were selected, according to Language test, Pure tone audiometry (PTA) & Auditory brain stem response (ABR). Group I included fourteen children with severe and/or severe to profound SNHL aided with proper hearing aids. Group II consisted of fourteen children with CI (MED-EL and Nucleus) and group III included fourteen children with normal hearing. Receptive, Expressive and total language quotients were calculated using the Arabic Language test. Assessment of psycholinguistic abilities was done using the Arabic version of the Illinois Test of Psycholinguistic abilities.
* Corresponding author at: King Fahd Hospital, Jeddah, Saudi Arabia. Mobile: +966 594183458. E-mail address: [email protected] (Hatem Ezzeldin Hassan). Peer review under responsibility of Egyptian Society of Ear, Nose, Throat and Allied Sciences.
Production and hosting by Elsevier 2090-0740 ª 2014 Production and hosting by Elsevier B.V. on behalf of Egyptian Society of Ear, Nose, Throat and Allied Sciences. http://dx.doi.org/10.1016/j.ejenta.2013.12.006
30
H.E. Hassan et al. Conclusion: HI individuals have poor auditory short-term memory (A-STM) in comparison to normal hearing individuals. Also, HI individuals have visual short-term memory (V-STM) better than normal hearing individuals. So, multisensory training is needed both in therapy sessions and classrooms with more focus on visual stimuli. ª 2014 Production and hosting by Elsevier B.V. on behalf of Egyptian Society of Ear, Nose, Throat and Allied Sciences.
1. Introduction Many congenitally sensorineural hearing loss (SNHL) children and cochlear implant (CI) recipients develop near-normal language skills. However, there is wide variation in individual outcomes following cochlear implantation, or using hearing aids.1 Some CI recipients or Hearing aids users never develop useable speech and oral language skills. The causes of this enormous variation in outcomes are only partly understood at the present time.2 Unfortunately, deaf students often have been found to have lower vocabulary skills than hearing age-matched peers. The size of their vocabulary tends to be smaller, the rate in which they acquire new vocabulary is slower, and they less easily develop new word meaning acquisition processes (Pisoni et al., 2000). Several researchers have pointed out that early identification of hearing loss (HL) has a positive effect on vocabulary development. The result of early intervention services provides support for both language and cognitive development. Aside from studies of early vocabulary development as part of language acquisition, studies of vocabulary in deaf learners have focused on the relation between vocabulary and reading.3 Psycholinguistic abilities, both auditory short-term memories (Auditory sequential memory, Sound blending, Auditory closure, Auditory association and Verbal expression) and Visual short term memories (Visual sequential memory, Visual reception, Visual closure and Manual expression) are important predictors for language development in normal children and children with disabilities. Surowieck et al.4 claimed that many children using cochlear implants are able to hear fine differences between speech sounds but are not progressing as wel1 as expected in receptive language ability. There is strong evidence from teachers that some children using cochlear implants have poor short-term auditory memory ability, which may be impeding their language development. Temporal ordering and short-term memory storage capacity involve higher order processing. Severe auditory deprivation prior to implantation may have caused auditory processing deficits at a cortical level. When cochlear implant implantation will be carried out especially at the very critical period of language development (before age of four), this will help the child, in his/her future life, not only with his/her hearing skills and communication but for his/her attention skills and behavior.5 The causes of these apparent differences in the success of treatment among HI & CI children are poorly understood. Therefore, early identification, understanding the nature of the disorders and proper intervention is warranted. However, to our knowledge, there have been no studies done to assess short term memory of Arabic speaking children with HI and CI. In this study we tried to have answers for the former questions, why there is a wide var-
iation in outcomes of rehabilitation of HI & CI regarding ASTM & V-STM. 1.1. Aim of the work The aim of this study was to assess the Psycholinguistic skills in Arabic speaking children with either SNHL or CI in comparison to controls in order to estimate the nature and extent of any specific deficit in these children that could explain the different prognostic results of language intervention. 1.2. Subjects and methods This study was conducted on children presented with delayed language development to Phoniatrics clinic, King Fahd Hospital Jeddah, during the period from October 2011 to July 2012. Three groups were selected, according to Language test, Pure tone audiometry (PTA) & Auditory brain stem response (ABR). Group I included fourteen children with severe and/or severe to profound SNHL aided with proper hearing aids. Group II consisted of fourteen children with CI (MED-EL & Nuleus) and group III included fourteen children with normal hearing. All children included in this study were subjected to a comprehensive language assessment protocol.6 - Patient’s interview. - Audiological evaluation including Auditory Brain Stem Response (ABR), Otoacoustic Emissions (OAEs) and Cochlear Microphonic (CM). - Psychometric evaluation by using Wechsler intelligence scale.8 - Objective language assessment was done using Standard Arabic language test to calculate Receptive, Expressive and total language quotients.6 - Assessment of psycholinguistic abilities was done using the Arabic version of the Illinois Test of Psycholinguistic Abilities.7 - Inclusion criteria: Individuals with severe and/or severe to profound SNHL, aided with proper hearing aids more than 5 years. Individuals using CI more than 5 years duration. - Exclusion criteria: Subjects with mental retardation (MR), below average mentality or any subject with behavioral problems, pervasive developmental disorders or with auditory neuropathy were excluded from the study. Children with Hearing Impairment (HI) were 8 boys and 6 girls. Their mean age was 8.3 ± 1.3 and age ranged from 6 to 12 years. The mean duration of H.As fitting was 5 ± 2 years. Children with Cochlear Implant (CI) were 7 boys and 7 girls. The mean age was 7.9 ± 0.9 years and age ranged from 6 to 12.6 years. The mean duration of CI was 5 ± 1 year. Both
Psycholinguistic abilities in cochlear implant and hearing impaired children groups of children (HI & CI) were attending regular individual language therapy sessions (two sessions per week, each session for 30 minutes for 2 years). Family counseling was given to the parents every three months to enhance the language abilities of the children. Control group (normal hearing children) were 7 boys and 7 girls. The mean age was 8.5 ± 1.2 and age ranged from 6 to 11.9 years. These children were selected randomly from members not suffering from any language and speech disorders. They were selected from outpatient clinic; King Fahd Hospital Jeddah, during the same period after taking their parents’ consent and they were used as a reference for their language development. They were attending because of other communication disorders as voice disorders. 2. Procedures and clinical tools 2.1. Assessment of short term memory Assessment of auditory and visual short term memory tasks was done for all children, using the Arabic version of the Illinois Test of Psycholinguistic Abilities.7 2.1.1. Auditory short-term memory 1- Auditory sequential memory (ASM): Sequences of digits (1–9) were presented verbally to the child and the child had to recall each digit sequence verbally. The task was presented using both auditory and visual cues; the child is allowed to see the face of the examiner. 2- Sound blending (SB): Combinations of 2–6 CV syllables were used. The child had to repeat each syllable combination in the right order 3- Auditory closure: List of 30 words. The examiner pronounced each word with one or more deleted sound. The child had to pronounce each word correctly. 4- Auditory association: Incomplete phrases analogues. The child had to complete the missed parts of this analogue verbally. 5- Verbal expression: 5 different objects were used and the child had to give full description of each object alone.
2.1.2. Assessment of Visual short-term memory 1- Visual sequential memory (VSM): Sequences of 2–8 abstract symbols presented to the child for 5 seconds.
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4- Manual expression: The child looks at 15 pictures of tools each presented lonely, and then he asked to imitate the function of the tool manually. The raw scores for each subtest were used to drive scaled scores for each task. The raw scores for each subtest were used to obtain the psycholinguistic age norms. The scaled scores are linear transformation of raw scores for each subtest according to the age levels. Statistical methods: Statistical package for social Sciences version 11 (SPSS, INC, Chicago, IL) under windows was used for data entry and data analysis. Descriptive statistics were done for continuous variables by mean, standard deviation (± SD) and range; and for qualitative data by number and percent. Student ‘t’ test and ANOVA test were used to compare continuous variables in various groups. Pearson’s correlation used to assess the association between the different parametric data. For all tests a probability (P) value less than 0.05 was considered significant. 3. Results Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding the different demographic data revealed insignificant statistically differences (>0.05) between the three groups regarding the age, gender distribution and IQ scores as shown in Table 1. Results of the Arabic language test indicated that CI children showed significant differences (<0.05) in all language parameters (Receptive, Expressive and total language age) in comparison to HI children. Control group showed highly significant differences (<0.01) in comparison to both CI and HI groups in all language parameters (Receptive, Expressive and total language age) as shown in Table 2. Results of auditory short-term memory subtests revealed significant differences (<0.05) in CI group in comparison to HI Group regarding all parameters of auditory short term memory (sound blending, auditory association, auditory closure and verbal expression). Also there were highly significant differences (<0.01) between control group and CI and HI groups in all auditory short term memory, as shown in Table 3. Results of visual short-term memory subtests revealed insignificant differences (>0.05) between HI group and CI group in all parameters of visual short memory (Visual sequential, visual reception, visual closure and manual expression). However, there were significant differences (<0.05) in all subtests of visual short memory (Visual sequential, visual reception, visual closure and manual expression) between HI and CI groups in comparison to control group as shown in Table 4. 4. Discussion
The child had to place the plates in the right order. 2- Visual reception: The child sees one picture for 3 seconds and he had to choose the one related to the former one. 3- Visual closure: Sheets of pictures. The examiner named a picture of an object, while the child was looking at it, then the child had to look at the full sheet of pictures and point to the biggest number of pictures similar to the former one.
The world we live in is overwhelmingly rich and complex. As human agents living in such a world we are constantly bombarded with large amounts of sensory information through multiple channels such as audition and vision. The outcome of language acquisition and learning is much different in hearing impaired children and normal hearing individuals, some hearing impaired and cochlear implant children showed considerable achievement regarding language development and
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H.E. Hassan et al.
Table 1 Comparison between the hearing impairment groups (HI), cochlear implant group (CI) and control group regarding the different demographic data. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA P value
Chronological age (years)
8.3 ± 1.3
7.8 ± 0.9
8.5 ± 1.2
>0.05
Gender Boys Girls IQ
8 (57.2%) 6 (42.8%) 100.5 ± 6
7 (50%) 7 (50%) 102.2 ± 5
7 (50%) 7 (50%) 101.9 ± 4
>0.05 >0.05
There were no statistically differences (>0.05) between the three groups regarding the age, gender distribution and IQ scores.
Table 2 Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding Language assessment. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA P value
t-Test P value
Receptive language quotient
55.5 ± 6
75.3 ± 4
98.2 ± 6
<0.001**
<0.05 * (a) <0.001** (b) <0.001** (c)
Expressive language quotient
53.4 ± 4
71.7 ± 5
97.8 ± 4
<0.001**
<0.05 * (a) <0.001** (b) <0.001* (c)
Total language quotient
54.7 ± 4
73.2 ± 3
97.3 ± 5
<0.001**
<0.05 * (a) <0.001** (b) <0.001** (c)
(a) HI vs. CI, (b) HI vs. control, (c) CI vs. control. * Significant. ** Highly significant.
Table 3 Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding auditory short-term memory subtests. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA P (sign.)
t-Test P (sign.)
Auditory sequential memory
33 ± 2
34 ± 6
40.4 ± 5
<0.001**
Sound blending
34 ± 6
35 ± 2
43 ± 4
<0.001**
Auditory closure
27 ± 2
29 ± 6
37 ± 3
<0.001**
Auditory association
26 ± 4
30 ± 3
42 ± 5
<0.001**
Verbal expression
24 ± 3
27 ± 2
49 ± 2
<0.001**
<0.05 * (a) <0.001** (b) <0.001** (c) <0.05 * (a) <0.001** (b) <0.001** (c) <0.05 (a) <0.001** (b) <0.001** (c) <0.05 * (a) <0.001** (b) <0.001** (c) <0.05 * (a) <0.001** (b) <0.001** (c)
(a) HI vs. CI, (b) HI vs. control, (c) CI vs. control. * Significant. ** Highly significant.
Psycholinguistic abilities in cochlear implant and hearing impaired children
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Table 4 Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding visual short-term memory subtests. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA test P value
t-Test P value
Visual sequential memory
47 ± 3
46 ± 4
36 ± 4
<0.05*
>0.05 (a) <0.05* (b) <0.05* (c)
Visual reception
45 ± 2
44 ± 4
34 ± 6
<0.05*
>0.05 (a) <0.05* (b) <0.05* (c)
Visual closure
64 ± 4
47 ± 2
37 ± 1
<0.05*
>0.05 (a) <0.05** (b) <0.05** (c)
Manual expression
46 ± 3
46 ± 5
38 ± 3
<0.05*
>0.05 (a) <0.05* (b) <0.05* (c)
(a) HI vs. CI, (b) HI vs. control, (c) CI vs. control. * Significant. ** Highly significant.
academic achievement, others fail to reach satisfactory results (Rose et al., 2008). Because of the wide variation between the results, authors tried to investigate other parameters as auditory short term memory and visual short term memory and their effects on language development and academic achievement. Rose et al. (2008) have examined the memory skills of cochlear implant users. Children with cochlear implants have been found to have shorter auditory digit spans compared to their normal-hearing. Moreover, they mentioned that Children using cochlear implants have also been found to perform worse than their normal-hearing on immediate memory tasks even when the stimuli are not presented auditory and recall does not require a verbal response. In this study attention was directed toward auditory and visual short-term memories, which seems to be related to cognitive processing tasks & language development. Thus, all children of the three groups were selected to be free from any neurological, behavioral deficits and within average mentality. In This study children with cochlear implantation were significantly better in all language skills in comparison with HI children. However all language parameters were significantly lower in HI and CI groups in comparison to normal control group. This finding could be explained by the increased ability of the children with CI to comprehend speech and improve their speech intelligibility in addition to faster acquisition of speech production and language development. Aline et al.9 highlighted the advantages of CI over hearing aids. They stated that cochlear implants were demonstrated to be the best current alternative for bilateral severe or profound hearing loss, achieving better results in speech perception and development in prelingual children when compared to conventional hearing aids. Prezbindowski and Lederberg10 and most (2012) revealed that normal language development depends on intact sensory channels and early hearing impairment has its impact on language acquisition & competence. Also, they have pointed out that early identification of hearing loss & early intervention services have a positive effect for both language and cognitive
development. Spencer and Marschark11 reported that Children with HI were found to have small size of their vocabulary, less semantic skills, slower rate of acquiring new vocabulary and less easily develop new word meaning acquisition processes.
5. Findings of Auditory short term memory In the current study, auditory short term memory tasks (sound blending, auditory association, auditory closure and verbal expression) were better in normal hearing children in comparison to CI & HI groups. These results coincide with that obtained by Bavelier12 who reported poor memory for sequential information among HI in relation to hearing individuals. These findings may point to the fact that early language development may enhance different auditory memory skills in HI individuals due to brain plasticity. Furthermore, introduction of verbal and non verbal materials to the child environment during infancy and early childhood has its effect on the development of A-STM. Laurie et al.13 stated that, from a theoretical standpoint, emergence of auditory perceptual milestones in young children would be expected to follow a trajectory of general perceptual development. This model describes the following three stages of development: sensory primitives (Level I), which characterizes basic sensory perceion; perceptual representations (Level II), which represents complex coding at higher neural levels; and higher order representations (Level III), which denotes cognitive/linguistic processing. However, Wilson et al.14 compared memory span performance of HI children with that of hearing children. Their results revealed that both groups were found to have comparable forward and backward digit span tasks suggesting that encoding of serial information does not entail directional dominance. Also they found that the HI children showed better auditory memory than hearing children. They suggest that memory in HI individuals who are fluent in sign language may have different characteristics than that of hearing individuals and perhaps HI individuals who rely on spoken language.
34 These diverse results may be explained by the difference in the nature of the task and to-be-remembered materials during application of different subtests. Those differences can lead to HI individuals having equal or worse auditory memory as compared with hearing individuals. In the current study, the mean scores of auditory association, auditory closure and verbal expression were better in CI groups in comparison to HI group. Fallon et al.15 mentioned that the evoked recorded potentials of early cochlear implant children suggest near-normal maturation of cortical layers of the brain and near normal development of auditory system; moreover they have better speech perception scores than HI children who are using hearing aids. Aline et al.9 mentioned that, based on several studies, cochlear implants were demonstrated to be the best current alternative for bilateral severe or profound hearing loss, achieving better results in speech perception and development in prelingual children when compared to conventional hearing aids. 6. Findings of Visual short term memory On testing the visual short term memory, all children who are normal hearing and hearing impaired were assessed with tasks that did not demand speech, to avoid absence of answers due to language impairments. The results were comparable for HI & CI groups regarding all subtests of V-STM. However, all subtests of V-STM (Visual Sequential memory, Visual reception, Visual closure & Manual expression) were better in HI and CI groups in comparison to normal control group. Also visiomotor skills as tested by manual expression subtest are better in HI & CI individuals than hearing individuals. These results coincide with that obtained by Bavelier16 and Sladen et al.17 Pelz and Canosa18 showed no differences between the HI groups & Hearing individuals regarding visual skills. Studies by Todman and Cowdy19 and Todman and Seedhouse20 found that HI children surpassed hearing peers in their memories for complex visual figures, but that the advantage disappeared when the figures were presented in parts and had to be recalled visually and/or verbally in sequential manner. Recently, Boutla et al.21 confirmed earlier findings suggesting that HI and normal hearing individuals have comparable working memory capacities, even if HI individuals tend to have shorter memory spans. Hay-McCutcheon et al.22 demonstrated that HI individuals have a variety of visuospatial advantages over hearing individuals, although some of those differences are a function of sign language fluency rather than auditory deprivation per se. Engel-Yeger et al.23 assumed that, whereas in hearing individuals’ attention is at its peak in the center of the visual field, HI individuals show greater attention at peripheral locations. They found enhanced peripheral processing in HI people and enhanced central processing in hearing people. 7. Conclusions
HI and CI individuals have V-STM better than normal hearing individuals. Visuomotor skills are more better in HI and CI individuals than hearing individuals.
H.E. Hassan et al. HI and CI individuals have decreased auditory verbal-STM which may be due to associated language impairment.
8. Recommendations
For HI and CI individuals, multisensory training is needed both in therapy sessions and classrooms with more focusing on visual stimuli. Auditory training program should include tasks to enhance and improve auditory short term memory span.
Conflict of interest None declared. References 1. Courtin C. The impact of sign language on the cognitive development of deaf children: the case of theories of mind. J Deaf Stud Deaf Educ. 2000;-5:266–276. 2. Marschark M, Convertino CM, Macias G, Monikowski CM, Sapere PM, Seewagen R. Understanding communication among deaf students who sign and speak: a trivial pursuit? Am Ann Deaf. 2007;152:415–424. 3. Ryugo DK, Limb CJ, Redd EE. Brain plasticity: the impact of the environment on the brain as it relates to hearing and Deafness. In: Niparko JK, editor. Cochlear implants: principles and practices, Philadelphia: Lippincott Williams & Wilkins; 2000. p. 33–57. ISBN 0-7817-17-82-5. 4. Surowiecki VN, Sarant J, Maruff P, Blamey PJ, Busby PA, Clark GM. Cognitive processing in children using cochlear implants: the relationship between visual memory, attention, and executive functions and developing language skills. Ann Otol Rhinol Laryngol Suppl. 2002;189:119–126. 5. Yucel E, Derim D. The effect of implantation age on visual attention skills. Source Hacettepe University, Department of Otorhinolaryngology. Int J Pediatr Otorhinolaryngol. 2008;72(6): 869–877. 6. Kotby MN, Khairy A, Barakah M, Rifaie N, EL-Shobary A. Language testing of Arabic speaking children. Proceeding of the XVIII world congress of the international association of logopedics and phoniatrics, (WCIALP’95), Cairo, Egypt: 1995. P. 263–266. 7. Azzam AA. Standardization and modification of Illinois test of psycholinguistic abilities in Egyptian children (MD Thesis) submitted to phoniatric clinic. Cairo, 2007, Ain Shams University. 8. Wechsler D. Wechsler intelligence scale for children. 3rd ed. San Antonio: The Psychological Corporation; 1991. 9. Aline Gomes Bittencourt, Ana Adelina Giantomassi Della Torre, Ricardo Ferreira Bento, Robinson Koji Tsuji, Rubens de Brito. Prelingual deafness: Benefits from cochlear implants versus conventional hearing aids. Int Arch Otorhinolaryngol 2012;16(3):387– 390. 10. Prezbindowski AK, Lederberg AR. Vocabulary assessment of deaf and hard-of-hearing children from infancy through the preschool years. J Deaf Stud Deaf Educ. 2003;8:383–400. 11. Spencer PE, Marschark M, eds. Advances in the spoken language development of deaf and hard-of-hearing children. New York: Oxford University Press; 2006. 12. Bavelier D. Similar working memory capacity but different serial short-term memory span in signers and speakers: theoretical and practical implications. Presentation at cognitive underpinnings of
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learning by deaf and hard-of-hearing students conference. Rochester, NY, 2007. Laurie S Eisenberg, Amy S Martinez, Arthur Boothroyd. Assessing auditory capabilities in young children. J Pediatr Otorhinolaryngol. 2007;71(9):1339–1350. Wilson M, Bettger JG, Niculae I, Klima ES. Modality of language shapes working memory: evidence from digit span and spatial span in ASL signers. J Deaf Stud Deaf Educ. 1997;2:152–162. Fallon JB, Irvine DR, Shepherd RK. Cochlear implants and brain plasticity. Hear Res. 2008;238(1–2):110–117 [Epub 2007 Sep 1. Format]. Quittner AL, Leibach P, Marciel K. The impact of cochlear implants on young deaf children: new methods to assess cognitive and behavioral development. Arch Otolaryngol Head Neck Surg. 2004;130(5):547–554. Sladen DP, Tharpe AM, Ashmead DH, Wesley Grantham D, Chun MM. Visual attention in deaf and normal hearing adults: effects of stimulus compatibility. J Speech Lang Hear Res. 2005;48(6):1529–1537.
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18. Pelz JB, Canosa R. Oculomotor behavior and perceptual strategies in complex tasks. Vision Res. 2001;41:3587–3596. 19. Todman J, Cowdy N. Processing of visual-action codes by deaf and hearing children: coding orientation or capacity? Intelligence. 1993;17:237–250. 20. Todman J, Seedhouse E. Visual-action code processing by deaf and hearing children. Lang Cogn Processes. 1994;9:129–141. 21. Boutla M, Supalla T, Newport EL, Bavelier D. Short-term memory span: Insights from sign language. Nat Neurosci. 2004;7:997–1002. 22. Hay-McCutcheon MJ, Pisoni DB, Hunt KK. Audiovisual asynchrony detection and speech perception in hearing impaired listeners with cochlear implants: a preliminary analysis. Int J Audiol. 2009;48(6):321–333. 23. Engel-Yeger B, Durr DH, Josman N. Comparison of memory and meta-memory abilities of children with cochlear implant and normal hearing peers. Disabil Rehabil. 2011;33(9):770–777.
Egyptian Society of Ear, Nose, Throat and Allied Sciences
Egyptian Journal of Ear, Nose, Throat and Allied Sciences www.ejentas.com
ORIGINAL ARTICLE
Psycholinguistic abilities in cochlear implant and hearing impaired children Hatem Ezzeldin Hassan a,b,*, Sally Taher Kheir Eldin c, Rasha Mohamed Al Kasaby d,e a
Otorhinolaryngology Department, Sohag University, Egypt King Fahd Hospital, Jeddah, Saudi Arabia c Otorhinolaryngology Department, Ain Shams University, Egypt d Otorhinolaryngology Department, Mansoura University, Egypt e Military Hospital, Riyadh, Saudi Arabia b
Received 20 September 2013; accepted 14 December 2013 Available online 17 January 2014
KEYWORDS Psycholinguistic; Cochlear implant; Language disorders; Hearing
Abstract Background: Many congenitally sensorineural hearing loss (SNHL) children and cochlear implant (CI) recipients develop near-normal language skills. However, there is a wide variation in individual outcomes following cochlear implantation, or using hearing aids. Some CI recipients or Hearing aids users never develop useable speech and oral language skills. The causes of this enormous variation in outcomes are only partly understood at the present time. So, the aim of this study was to assess the psycholinguistic skills in Arabic speaking children with either SNHL or CI in comparison to normal controls in order to estimate the nature and extent of any specific deficit in these children that could explain the different prognostic results of language intervention. Subjects and methods: Three groups were selected, according to Language test, Pure tone audiometry (PTA) & Auditory brain stem response (ABR). Group I included fourteen children with severe and/or severe to profound SNHL aided with proper hearing aids. Group II consisted of fourteen children with CI (MED-EL and Nucleus) and group III included fourteen children with normal hearing. Receptive, Expressive and total language quotients were calculated using the Arabic Language test. Assessment of psycholinguistic abilities was done using the Arabic version of the Illinois Test of Psycholinguistic abilities.
* Corresponding author at: King Fahd Hospital, Jeddah, Saudi Arabia. Mobile: +966 594183458. E-mail address: [email protected] (Hatem Ezzeldin Hassan). Peer review under responsibility of Egyptian Society of Ear, Nose, Throat and Allied Sciences.
Production and hosting by Elsevier 2090-0740 ª 2014 Production and hosting by Elsevier B.V. on behalf of Egyptian Society of Ear, Nose, Throat and Allied Sciences. http://dx.doi.org/10.1016/j.ejenta.2013.12.006
30
H.E. Hassan et al. Conclusion: HI individuals have poor auditory short-term memory (A-STM) in comparison to normal hearing individuals. Also, HI individuals have visual short-term memory (V-STM) better than normal hearing individuals. So, multisensory training is needed both in therapy sessions and classrooms with more focus on visual stimuli. ª 2014 Production and hosting by Elsevier B.V. on behalf of Egyptian Society of Ear, Nose, Throat and Allied Sciences.
1. Introduction Many congenitally sensorineural hearing loss (SNHL) children and cochlear implant (CI) recipients develop near-normal language skills. However, there is wide variation in individual outcomes following cochlear implantation, or using hearing aids.1 Some CI recipients or Hearing aids users never develop useable speech and oral language skills. The causes of this enormous variation in outcomes are only partly understood at the present time.2 Unfortunately, deaf students often have been found to have lower vocabulary skills than hearing age-matched peers. The size of their vocabulary tends to be smaller, the rate in which they acquire new vocabulary is slower, and they less easily develop new word meaning acquisition processes (Pisoni et al., 2000). Several researchers have pointed out that early identification of hearing loss (HL) has a positive effect on vocabulary development. The result of early intervention services provides support for both language and cognitive development. Aside from studies of early vocabulary development as part of language acquisition, studies of vocabulary in deaf learners have focused on the relation between vocabulary and reading.3 Psycholinguistic abilities, both auditory short-term memories (Auditory sequential memory, Sound blending, Auditory closure, Auditory association and Verbal expression) and Visual short term memories (Visual sequential memory, Visual reception, Visual closure and Manual expression) are important predictors for language development in normal children and children with disabilities. Surowieck et al.4 claimed that many children using cochlear implants are able to hear fine differences between speech sounds but are not progressing as wel1 as expected in receptive language ability. There is strong evidence from teachers that some children using cochlear implants have poor short-term auditory memory ability, which may be impeding their language development. Temporal ordering and short-term memory storage capacity involve higher order processing. Severe auditory deprivation prior to implantation may have caused auditory processing deficits at a cortical level. When cochlear implant implantation will be carried out especially at the very critical period of language development (before age of four), this will help the child, in his/her future life, not only with his/her hearing skills and communication but for his/her attention skills and behavior.5 The causes of these apparent differences in the success of treatment among HI & CI children are poorly understood. Therefore, early identification, understanding the nature of the disorders and proper intervention is warranted. However, to our knowledge, there have been no studies done to assess short term memory of Arabic speaking children with HI and CI. In this study we tried to have answers for the former questions, why there is a wide var-
iation in outcomes of rehabilitation of HI & CI regarding ASTM & V-STM. 1.1. Aim of the work The aim of this study was to assess the Psycholinguistic skills in Arabic speaking children with either SNHL or CI in comparison to controls in order to estimate the nature and extent of any specific deficit in these children that could explain the different prognostic results of language intervention. 1.2. Subjects and methods This study was conducted on children presented with delayed language development to Phoniatrics clinic, King Fahd Hospital Jeddah, during the period from October 2011 to July 2012. Three groups were selected, according to Language test, Pure tone audiometry (PTA) & Auditory brain stem response (ABR). Group I included fourteen children with severe and/or severe to profound SNHL aided with proper hearing aids. Group II consisted of fourteen children with CI (MED-EL & Nuleus) and group III included fourteen children with normal hearing. All children included in this study were subjected to a comprehensive language assessment protocol.6 - Patient’s interview. - Audiological evaluation including Auditory Brain Stem Response (ABR), Otoacoustic Emissions (OAEs) and Cochlear Microphonic (CM). - Psychometric evaluation by using Wechsler intelligence scale.8 - Objective language assessment was done using Standard Arabic language test to calculate Receptive, Expressive and total language quotients.6 - Assessment of psycholinguistic abilities was done using the Arabic version of the Illinois Test of Psycholinguistic Abilities.7 - Inclusion criteria: Individuals with severe and/or severe to profound SNHL, aided with proper hearing aids more than 5 years. Individuals using CI more than 5 years duration. - Exclusion criteria: Subjects with mental retardation (MR), below average mentality or any subject with behavioral problems, pervasive developmental disorders or with auditory neuropathy were excluded from the study. Children with Hearing Impairment (HI) were 8 boys and 6 girls. Their mean age was 8.3 ± 1.3 and age ranged from 6 to 12 years. The mean duration of H.As fitting was 5 ± 2 years. Children with Cochlear Implant (CI) were 7 boys and 7 girls. The mean age was 7.9 ± 0.9 years and age ranged from 6 to 12.6 years. The mean duration of CI was 5 ± 1 year. Both
Psycholinguistic abilities in cochlear implant and hearing impaired children groups of children (HI & CI) were attending regular individual language therapy sessions (two sessions per week, each session for 30 minutes for 2 years). Family counseling was given to the parents every three months to enhance the language abilities of the children. Control group (normal hearing children) were 7 boys and 7 girls. The mean age was 8.5 ± 1.2 and age ranged from 6 to 11.9 years. These children were selected randomly from members not suffering from any language and speech disorders. They were selected from outpatient clinic; King Fahd Hospital Jeddah, during the same period after taking their parents’ consent and they were used as a reference for their language development. They were attending because of other communication disorders as voice disorders. 2. Procedures and clinical tools 2.1. Assessment of short term memory Assessment of auditory and visual short term memory tasks was done for all children, using the Arabic version of the Illinois Test of Psycholinguistic Abilities.7 2.1.1. Auditory short-term memory 1- Auditory sequential memory (ASM): Sequences of digits (1–9) were presented verbally to the child and the child had to recall each digit sequence verbally. The task was presented using both auditory and visual cues; the child is allowed to see the face of the examiner. 2- Sound blending (SB): Combinations of 2–6 CV syllables were used. The child had to repeat each syllable combination in the right order 3- Auditory closure: List of 30 words. The examiner pronounced each word with one or more deleted sound. The child had to pronounce each word correctly. 4- Auditory association: Incomplete phrases analogues. The child had to complete the missed parts of this analogue verbally. 5- Verbal expression: 5 different objects were used and the child had to give full description of each object alone.
2.1.2. Assessment of Visual short-term memory 1- Visual sequential memory (VSM): Sequences of 2–8 abstract symbols presented to the child for 5 seconds.
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4- Manual expression: The child looks at 15 pictures of tools each presented lonely, and then he asked to imitate the function of the tool manually. The raw scores for each subtest were used to drive scaled scores for each task. The raw scores for each subtest were used to obtain the psycholinguistic age norms. The scaled scores are linear transformation of raw scores for each subtest according to the age levels. Statistical methods: Statistical package for social Sciences version 11 (SPSS, INC, Chicago, IL) under windows was used for data entry and data analysis. Descriptive statistics were done for continuous variables by mean, standard deviation (± SD) and range; and for qualitative data by number and percent. Student ‘t’ test and ANOVA test were used to compare continuous variables in various groups. Pearson’s correlation used to assess the association between the different parametric data. For all tests a probability (P) value less than 0.05 was considered significant. 3. Results Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding the different demographic data revealed insignificant statistically differences (>0.05) between the three groups regarding the age, gender distribution and IQ scores as shown in Table 1. Results of the Arabic language test indicated that CI children showed significant differences (<0.05) in all language parameters (Receptive, Expressive and total language age) in comparison to HI children. Control group showed highly significant differences (<0.01) in comparison to both CI and HI groups in all language parameters (Receptive, Expressive and total language age) as shown in Table 2. Results of auditory short-term memory subtests revealed significant differences (<0.05) in CI group in comparison to HI Group regarding all parameters of auditory short term memory (sound blending, auditory association, auditory closure and verbal expression). Also there were highly significant differences (<0.01) between control group and CI and HI groups in all auditory short term memory, as shown in Table 3. Results of visual short-term memory subtests revealed insignificant differences (>0.05) between HI group and CI group in all parameters of visual short memory (Visual sequential, visual reception, visual closure and manual expression). However, there were significant differences (<0.05) in all subtests of visual short memory (Visual sequential, visual reception, visual closure and manual expression) between HI and CI groups in comparison to control group as shown in Table 4. 4. Discussion
The child had to place the plates in the right order. 2- Visual reception: The child sees one picture for 3 seconds and he had to choose the one related to the former one. 3- Visual closure: Sheets of pictures. The examiner named a picture of an object, while the child was looking at it, then the child had to look at the full sheet of pictures and point to the biggest number of pictures similar to the former one.
The world we live in is overwhelmingly rich and complex. As human agents living in such a world we are constantly bombarded with large amounts of sensory information through multiple channels such as audition and vision. The outcome of language acquisition and learning is much different in hearing impaired children and normal hearing individuals, some hearing impaired and cochlear implant children showed considerable achievement regarding language development and
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H.E. Hassan et al.
Table 1 Comparison between the hearing impairment groups (HI), cochlear implant group (CI) and control group regarding the different demographic data. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA P value
Chronological age (years)
8.3 ± 1.3
7.8 ± 0.9
8.5 ± 1.2
>0.05
Gender Boys Girls IQ
8 (57.2%) 6 (42.8%) 100.5 ± 6
7 (50%) 7 (50%) 102.2 ± 5
7 (50%) 7 (50%) 101.9 ± 4
>0.05 >0.05
There were no statistically differences (>0.05) between the three groups regarding the age, gender distribution and IQ scores.
Table 2 Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding Language assessment. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA P value
t-Test P value
Receptive language quotient
55.5 ± 6
75.3 ± 4
98.2 ± 6
<0.001**
<0.05 * (a) <0.001** (b) <0.001** (c)
Expressive language quotient
53.4 ± 4
71.7 ± 5
97.8 ± 4
<0.001**
<0.05 * (a) <0.001** (b) <0.001* (c)
Total language quotient
54.7 ± 4
73.2 ± 3
97.3 ± 5
<0.001**
<0.05 * (a) <0.001** (b) <0.001** (c)
(a) HI vs. CI, (b) HI vs. control, (c) CI vs. control. * Significant. ** Highly significant.
Table 3 Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding auditory short-term memory subtests. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA P (sign.)
t-Test P (sign.)
Auditory sequential memory
33 ± 2
34 ± 6
40.4 ± 5
<0.001**
Sound blending
34 ± 6
35 ± 2
43 ± 4
<0.001**
Auditory closure
27 ± 2
29 ± 6
37 ± 3
<0.001**
Auditory association
26 ± 4
30 ± 3
42 ± 5
<0.001**
Verbal expression
24 ± 3
27 ± 2
49 ± 2
<0.001**
<0.05 * (a) <0.001** (b) <0.001** (c) <0.05 * (a) <0.001** (b) <0.001** (c) <0.05 (a) <0.001** (b) <0.001** (c) <0.05 * (a) <0.001** (b) <0.001** (c) <0.05 * (a) <0.001** (b) <0.001** (c)
(a) HI vs. CI, (b) HI vs. control, (c) CI vs. control. * Significant. ** Highly significant.
Psycholinguistic abilities in cochlear implant and hearing impaired children
33
Table 4 Comparison between the hearing impairment group (HI), cochlear implant group (CI) and control group regarding visual short-term memory subtests. Variables
HI Mean ± SD
CI Mean ± SD
Control Mean ± SD
ANOVA test P value
t-Test P value
Visual sequential memory
47 ± 3
46 ± 4
36 ± 4
<0.05*
>0.05 (a) <0.05* (b) <0.05* (c)
Visual reception
45 ± 2
44 ± 4
34 ± 6
<0.05*
>0.05 (a) <0.05* (b) <0.05* (c)
Visual closure
64 ± 4
47 ± 2
37 ± 1
<0.05*
>0.05 (a) <0.05** (b) <0.05** (c)
Manual expression
46 ± 3
46 ± 5
38 ± 3
<0.05*
>0.05 (a) <0.05* (b) <0.05* (c)
(a) HI vs. CI, (b) HI vs. control, (c) CI vs. control. * Significant. ** Highly significant.
academic achievement, others fail to reach satisfactory results (Rose et al., 2008). Because of the wide variation between the results, authors tried to investigate other parameters as auditory short term memory and visual short term memory and their effects on language development and academic achievement. Rose et al. (2008) have examined the memory skills of cochlear implant users. Children with cochlear implants have been found to have shorter auditory digit spans compared to their normal-hearing. Moreover, they mentioned that Children using cochlear implants have also been found to perform worse than their normal-hearing on immediate memory tasks even when the stimuli are not presented auditory and recall does not require a verbal response. In this study attention was directed toward auditory and visual short-term memories, which seems to be related to cognitive processing tasks & language development. Thus, all children of the three groups were selected to be free from any neurological, behavioral deficits and within average mentality. In This study children with cochlear implantation were significantly better in all language skills in comparison with HI children. However all language parameters were significantly lower in HI and CI groups in comparison to normal control group. This finding could be explained by the increased ability of the children with CI to comprehend speech and improve their speech intelligibility in addition to faster acquisition of speech production and language development. Aline et al.9 highlighted the advantages of CI over hearing aids. They stated that cochlear implants were demonstrated to be the best current alternative for bilateral severe or profound hearing loss, achieving better results in speech perception and development in prelingual children when compared to conventional hearing aids. Prezbindowski and Lederberg10 and most (2012) revealed that normal language development depends on intact sensory channels and early hearing impairment has its impact on language acquisition & competence. Also, they have pointed out that early identification of hearing loss & early intervention services have a positive effect for both language and cognitive
development. Spencer and Marschark11 reported that Children with HI were found to have small size of their vocabulary, less semantic skills, slower rate of acquiring new vocabulary and less easily develop new word meaning acquisition processes.
5. Findings of Auditory short term memory In the current study, auditory short term memory tasks (sound blending, auditory association, auditory closure and verbal expression) were better in normal hearing children in comparison to CI & HI groups. These results coincide with that obtained by Bavelier12 who reported poor memory for sequential information among HI in relation to hearing individuals. These findings may point to the fact that early language development may enhance different auditory memory skills in HI individuals due to brain plasticity. Furthermore, introduction of verbal and non verbal materials to the child environment during infancy and early childhood has its effect on the development of A-STM. Laurie et al.13 stated that, from a theoretical standpoint, emergence of auditory perceptual milestones in young children would be expected to follow a trajectory of general perceptual development. This model describes the following three stages of development: sensory primitives (Level I), which characterizes basic sensory perceion; perceptual representations (Level II), which represents complex coding at higher neural levels; and higher order representations (Level III), which denotes cognitive/linguistic processing. However, Wilson et al.14 compared memory span performance of HI children with that of hearing children. Their results revealed that both groups were found to have comparable forward and backward digit span tasks suggesting that encoding of serial information does not entail directional dominance. Also they found that the HI children showed better auditory memory than hearing children. They suggest that memory in HI individuals who are fluent in sign language may have different characteristics than that of hearing individuals and perhaps HI individuals who rely on spoken language.
34 These diverse results may be explained by the difference in the nature of the task and to-be-remembered materials during application of different subtests. Those differences can lead to HI individuals having equal or worse auditory memory as compared with hearing individuals. In the current study, the mean scores of auditory association, auditory closure and verbal expression were better in CI groups in comparison to HI group. Fallon et al.15 mentioned that the evoked recorded potentials of early cochlear implant children suggest near-normal maturation of cortical layers of the brain and near normal development of auditory system; moreover they have better speech perception scores than HI children who are using hearing aids. Aline et al.9 mentioned that, based on several studies, cochlear implants were demonstrated to be the best current alternative for bilateral severe or profound hearing loss, achieving better results in speech perception and development in prelingual children when compared to conventional hearing aids. 6. Findings of Visual short term memory On testing the visual short term memory, all children who are normal hearing and hearing impaired were assessed with tasks that did not demand speech, to avoid absence of answers due to language impairments. The results were comparable for HI & CI groups regarding all subtests of V-STM. However, all subtests of V-STM (Visual Sequential memory, Visual reception, Visual closure & Manual expression) were better in HI and CI groups in comparison to normal control group. Also visiomotor skills as tested by manual expression subtest are better in HI & CI individuals than hearing individuals. These results coincide with that obtained by Bavelier16 and Sladen et al.17 Pelz and Canosa18 showed no differences between the HI groups & Hearing individuals regarding visual skills. Studies by Todman and Cowdy19 and Todman and Seedhouse20 found that HI children surpassed hearing peers in their memories for complex visual figures, but that the advantage disappeared when the figures were presented in parts and had to be recalled visually and/or verbally in sequential manner. Recently, Boutla et al.21 confirmed earlier findings suggesting that HI and normal hearing individuals have comparable working memory capacities, even if HI individuals tend to have shorter memory spans. Hay-McCutcheon et al.22 demonstrated that HI individuals have a variety of visuospatial advantages over hearing individuals, although some of those differences are a function of sign language fluency rather than auditory deprivation per se. Engel-Yeger et al.23 assumed that, whereas in hearing individuals’ attention is at its peak in the center of the visual field, HI individuals show greater attention at peripheral locations. They found enhanced peripheral processing in HI people and enhanced central processing in hearing people. 7. Conclusions
HI and CI individuals have V-STM better than normal hearing individuals. Visuomotor skills are more better in HI and CI individuals than hearing individuals.
H.E. Hassan et al. HI and CI individuals have decreased auditory verbal-STM which may be due to associated language impairment.
8. Recommendations
For HI and CI individuals, multisensory training is needed both in therapy sessions and classrooms with more focusing on visual stimuli. Auditory training program should include tasks to enhance and improve auditory short term memory span.
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