How to read when speech sounds different? A longitudinal study of the development of reading strategies in children with cochlear implants
Previous research demonstrate that deaf children with cochlear implants (CI) have problems with basic decoding skills, i. e. reading letter by letter. This is likely due to poor phonological skills caused by less detail in the auditory stimulation from the CI. Phonological skills are strongly associated with reading development in other populations of children. The aim of the planned research is to increase our knowledge about reading development in children with CI. The main focus is to study the children's development of reading strategies from the early stage of decoding letter by letter to later stages of quick and efficient word recognition. A second aim is to investigate what cognitive factors affect the development of reading strategies and how these may change over time. We will study the children's development of cognitive skills and reading ability longitudinally for 3 years (age 8-10) when children typically go from basic decoding to instant word recognition. All children are tested at a regular follow up at the CI program, Karolinska University Hospital and we will have access to information about their hearing levels etc.This project is expected to provide unique theoretical knowledge about the mechanisms of reading development in individuals with poor phonological skills, which also applies to other populations of children.
Final report
Purpose
The main purpose of this project has been to study the development of reading ability, in particular decoding, i.e. the ability to read words, in children with cochlear implants (CI) during a period of three years. A second purpose has been to explore the cognitive and linguistic skills that affect the children’s reading development. More specific research questions have been investigated in the separate studies of this project.
Procedure
The children’s reading ability has been assessed at three points in time, once per year, in connection to a clinical follow up at their CI-clinic. In addition, they have been assessed on various aspects of language, cognition, and speech perception both on the same occasions as the reading assessments and on separate occasions. The children’s wellbeing and psychosocial factors have been investigated in questionnaires.
Forty-five children with CI participated at the start of the project. Five children have, during the course of the project, been diagnosed with additional disorders that affect their performance on the tasks that we measure. Those children have either chosen quit their participation or their results have been excluded from the analyses. Some additional children have not been able to participate in all tasks at all test sessions. Therefore, the number of participants vary between the published studies.
Important results and conclusions
1. In a first study (Wass, Löfkvist et al., 2019), we investigated the associations between orthographic learning, i.e. the children’s ability to learn the spelling of words they had not seen in print before, and cognitive and linguistic skills. Orthographic learning is important because it allows us recognize written words instantly and thereby it is the key to quick and fluent reading. The results showed that orthographic learning was strongly associated with the ability to read words letter by letter in the process referred to as phonological decoding. The children with CI thus appear to learn the spelling of words through phonological decoding.
We also found strong relationships between orthographic learning and oral vocabulary, that is the comprehension of words and the ability to recall words from long term memory. Also, phonological skills (the ability to manipulate speech sounds, e.g. to say ’sun’ without an ’s’ ) was found to be strongly related to orthographic learning.
Important conclusions of this research are that all three skills that are strongly associated with orthographic learning (phonological decoding, vocabulary, and phonological skills) are possible for children to train and improve. Thereby also reading ability and orthographic learning should be expected to improve.
Another important conclusion is that children with CI, despite their compromised hearing seem to memorize the spelling of words in a similar fashion a typically hearing children. This should be taken into consideration when designing training and intervention for children with CI.
2. In a second study (Wass, Anmyr et al., 2019) we investigated reading comprehension and the factors associated with reading comprehension when the children are 11 years of age. Both cognitive/linguistic predictors and demographic predictors, such as hearing levels, age at implantation and parental education, were investigated. The results showed that almost 90% of the children performed within the normal range of children with normal hearing on the reading comprehension measure. The strongest predictor of performance on the task of reading comprehension was receptive vocabulary. Based on these results, we conclude that children with CI at age 11 generally have enough word reading skills and therefore differences in performance are better explained by their receptive vocabulary. Neither speech perception nor age at implantation were significantly related to reading comprehension in our sample.
3. We have also analyzed the children’s development of word reading longitudinally from the start to the end of the project. This analysis has shown that vocabulary and the ability to quickly retrieve words from memory are the strongest predictors of word reading development over time.
Discussion
Our results suggest that oral vocabulary and the ability to quickly retrieve words from memory are important predictors of the reading development of children with CI, both cross-sectionally and longitudinally. Phonological skills and phonological decoding are further important for orthographic learning and thereby the development of fluent reading.
These results are important because we know from previous research that children with CI have problems with all of these three skills that are in turn important for reading development. Thus, the next step in both research and teaching would be to support children with CI in extending their oral vocabularies, improving their phonological skills and practice phonological decoding. This type of intervention would likely be efficient for the reading development of this population.
New research questions
Based on the findings that receptive vocabulary is very important for the development of reading ability and the knowledge that children with CI often have a less extensive vocabulary that typically hearing peers, we wanted to analyze the semantic structure of the children’s vocabularies.
In a new study (Socher et al., in progress) we have used computational modeling technique to model the children’s vocabularies, based on their performance in semantic fluency tests where they are asked to come up with as many words of a certain semantic category as possible within 60 seconds. The differences in semantic network structure disappear after controlling for length of hearing deprivation and thus these results suggest that differences in structure between children with CI and typically hearing peers are due to the later start of language development in children with CI.
Collaboration and spreading of results
Lectures
Information for parents of children with CI, organized by Hörselvården in Region Norrbotten, May 2019.
Teaching at the Special Education Program at LTU, 2017-2020
Teaching at the Master’s program in ”Audiopedagogikk”, University of Oslo 2016-2019.
Special Education Program Stockholm university, 2017
Svenska pedagogiska audiologiska föreningens (SPAF) national conference in Uppsala, May 3-5, 2017.
Information day about Cochlear Implants (CI) at Karolinska University Hospital Huddinge, 28 november 2019. The lecture was broadcasted to hearing clinics in the majority of the Swedish regions.
Press
Results from the project have been published in local press and media in Norrbotten: NSD1 and Norrbottenskuriren2, MedTech Magazine3, HRF’s journal Auris and an interview in the local radio channel, P4 Norrbotten4.
The main purpose of this project has been to study the development of reading ability, in particular decoding, i.e. the ability to read words, in children with cochlear implants (CI) during a period of three years. A second purpose has been to explore the cognitive and linguistic skills that affect the children’s reading development. More specific research questions have been investigated in the separate studies of this project.
Procedure
The children’s reading ability has been assessed at three points in time, once per year, in connection to a clinical follow up at their CI-clinic. In addition, they have been assessed on various aspects of language, cognition, and speech perception both on the same occasions as the reading assessments and on separate occasions. The children’s wellbeing and psychosocial factors have been investigated in questionnaires.
Forty-five children with CI participated at the start of the project. Five children have, during the course of the project, been diagnosed with additional disorders that affect their performance on the tasks that we measure. Those children have either chosen quit their participation or their results have been excluded from the analyses. Some additional children have not been able to participate in all tasks at all test sessions. Therefore, the number of participants vary between the published studies.
Important results and conclusions
1. In a first study (Wass, Löfkvist et al., 2019), we investigated the associations between orthographic learning, i.e. the children’s ability to learn the spelling of words they had not seen in print before, and cognitive and linguistic skills. Orthographic learning is important because it allows us recognize written words instantly and thereby it is the key to quick and fluent reading. The results showed that orthographic learning was strongly associated with the ability to read words letter by letter in the process referred to as phonological decoding. The children with CI thus appear to learn the spelling of words through phonological decoding.
We also found strong relationships between orthographic learning and oral vocabulary, that is the comprehension of words and the ability to recall words from long term memory. Also, phonological skills (the ability to manipulate speech sounds, e.g. to say ’sun’ without an ’s’ ) was found to be strongly related to orthographic learning.
Important conclusions of this research are that all three skills that are strongly associated with orthographic learning (phonological decoding, vocabulary, and phonological skills) are possible for children to train and improve. Thereby also reading ability and orthographic learning should be expected to improve.
Another important conclusion is that children with CI, despite their compromised hearing seem to memorize the spelling of words in a similar fashion a typically hearing children. This should be taken into consideration when designing training and intervention for children with CI.
2. In a second study (Wass, Anmyr et al., 2019) we investigated reading comprehension and the factors associated with reading comprehension when the children are 11 years of age. Both cognitive/linguistic predictors and demographic predictors, such as hearing levels, age at implantation and parental education, were investigated. The results showed that almost 90% of the children performed within the normal range of children with normal hearing on the reading comprehension measure. The strongest predictor of performance on the task of reading comprehension was receptive vocabulary. Based on these results, we conclude that children with CI at age 11 generally have enough word reading skills and therefore differences in performance are better explained by their receptive vocabulary. Neither speech perception nor age at implantation were significantly related to reading comprehension in our sample.
3. We have also analyzed the children’s development of word reading longitudinally from the start to the end of the project. This analysis has shown that vocabulary and the ability to quickly retrieve words from memory are the strongest predictors of word reading development over time.
Discussion
Our results suggest that oral vocabulary and the ability to quickly retrieve words from memory are important predictors of the reading development of children with CI, both cross-sectionally and longitudinally. Phonological skills and phonological decoding are further important for orthographic learning and thereby the development of fluent reading.
These results are important because we know from previous research that children with CI have problems with all of these three skills that are in turn important for reading development. Thus, the next step in both research and teaching would be to support children with CI in extending their oral vocabularies, improving their phonological skills and practice phonological decoding. This type of intervention would likely be efficient for the reading development of this population.
New research questions
Based on the findings that receptive vocabulary is very important for the development of reading ability and the knowledge that children with CI often have a less extensive vocabulary that typically hearing peers, we wanted to analyze the semantic structure of the children’s vocabularies.
In a new study (Socher et al., in progress) we have used computational modeling technique to model the children’s vocabularies, based on their performance in semantic fluency tests where they are asked to come up with as many words of a certain semantic category as possible within 60 seconds. The differences in semantic network structure disappear after controlling for length of hearing deprivation and thus these results suggest that differences in structure between children with CI and typically hearing peers are due to the later start of language development in children with CI.
Collaboration and spreading of results
Lectures
Information for parents of children with CI, organized by Hörselvården in Region Norrbotten, May 2019.
Teaching at the Special Education Program at LTU, 2017-2020
Teaching at the Master’s program in ”Audiopedagogikk”, University of Oslo 2016-2019.
Special Education Program Stockholm university, 2017
Svenska pedagogiska audiologiska föreningens (SPAF) national conference in Uppsala, May 3-5, 2017.
Information day about Cochlear Implants (CI) at Karolinska University Hospital Huddinge, 28 november 2019. The lecture was broadcasted to hearing clinics in the majority of the Swedish regions.
Press
Results from the project have been published in local press and media in Norrbotten: NSD1 and Norrbottenskuriren2, MedTech Magazine3, HRF’s journal Auris and an interview in the local radio channel, P4 Norrbotten4.