Children with Down syndrome (DS) struggle with verbal short-term memory, which can have negative effects on overall language comprehension (Lecas, Mazaud, & Reibel, 2011). Working memory is a huge contributor to cognitive and linguistic skills, including comprehension of texts and stories (Lecas, Mazaud, & Reibel, 2011). However, recent studies find that an active visual memory can account for deficits in the verbal short-term memory (Lecas, Mazaud, & Reibel, 2011). By allowing DS children to interact with verbal information in a visual manner, it is hoped that they will be more successful in recalling and comprehending information in a story (Lecas, Mazaud, & Reibel, 2011). Research has shown that DS children can have strong skills in word reading and accuracy, but considerably weaker skills in comprehension (van Bysterveldt & Gillon, 2014). Individuals with DS have deficits in language abilities, which result in impaired reading comprehension.

One of the main characteristics in individuals with Down syndrome is impaired language abilities (Witecy & Penke, 2017). These language abilities have a late onset, and are developed at a slower pace compared to typically developing individuals (Witecy & Penke, 2017). Witecy and Penke indicated that as chronological age increases, so does mental age (2017). However, nonverbal cognitive skills appear to plateau after adolescence. This idea means that comprehension increases in children with Down syndrome, but there is no change adults (Witecy & Penke, 2017). They found that overall comprehension skills stop developing during the transition from adolescence to adulthood (Witecy & Penke, 2017). While it is frustrating that they cannot better their language abilities through a certain age, these skills do not decline into adulthood (Witecy & Penke, 2017). There were similar results in terms of nonverbal cognition and receptive language skills, showing an improvement in skill in children, but no improvement in adults.

Research shows that individuals with Down syndrome continue growing their language skills through adolescence, but plateau afterward (van Bysteryeldt & Gillon, 2014). In general, regularly placed students score higher in academic, speech, and language skills compared to their peers with special needs. van Bysteryeldt and Gillon studied the differences in academic development in DS children placed in regular schools compared to special education (2014). Participants answered over 800 questions in a questionnaire, and researchers found that language skills continued to advance up until the age of 12 (van Bysteryeldt & Gillon, 2014). Results also showed that girls earned higher scores in self-help and language skills, while boys earned higher scores in computer skills. Language skills were measured by length of utterances and active vocabulary (van Bysteryeldt & Gillon, 2014).

Laws and collegues researched the difference in reading comprehension skills in DS compared to TD children. Generally speaking, comprehension is dependent on listening and reading abilities. These abilities come from complex cognitive and linguistic processes (Laws, Brown, & Main, 2016). Many DS children become proficient in reading words, but this progress is not directly connected to reading comprehension (Laws, Brown, & Main, 2016). To investigate reading comprehension, they measured listening comprehension, vocabulary knowledge, reading accuracy, and phonological awareness (Laws, Brown, & Main, 2016). They found that DS children performed significantly worse on passage reading comprehension compared to TD children. DS children did not understand as many written sentences as their TD counterparts, and also experienced deficits in vocabulary and phonology awareness. With impairments in these regions, individuals with DS may rely more on visual stimuli to connect a verbal or written word to their meaning (Laws, Brown, & Main, 2016).

Researchers wanted to discover if there are any ways to improve language abilities. In order to do so, they followed Paul, a 17-year-old adolescent, was an individual with Down syndrome. Paul’s family includes his parents, who work in the medical field, and his younger brother. He began attending nursery school part-time at age three, and moved onto primary school part-time at age 6. At age 14, Paul attended a Special Needs School where he was part of the Introductory and Initial Vocational Training Section. As part of this program, he participated in pre-vocational workshops as well as both educational and expressive activities. Paul also worked with a psychotherapist. Paul was pleasant, but also anxious. He enjoyed reading, listening to music, and writing stories. He was a motivated individual who worked very hard during his sessions. All of these characteristics made him a good candidate for this study. (Lecas, Mazaud, & Reibel, 2011).

In order to learn from Paul, researchers needed to complete an assessment of his cognitive processes in seven different areas. In terms of general intellectual skills, he had a verbal IQ of 46 and a performance IQ of 46, with a total IQ score of 41. These results were obtained using the Wechsler Intelligence Scale for Children (WISC III). For language abilities, they found that Paul was at a mental age of 7 years and 9 months. He was successful in reading aloud and practicing good pronunciation. (Lecas, Mazaud, & Reibel, 2011)

Paul’s memory span was measured by counting and reading span tests. For the reading span test, Paul had to read one sentence at a time aloud and remember the last word. After reading 2-4 sentences, he had to recall the last words. He was successful when it involved two sentences, but could not recall when the content exceeded two sentences, indicated difficulty in verbal short term memory. Tests also showed that Paul had efficient abilities in visual working memory. Another part of the assessment was text comprehension. Paul read stories and was asked to recall the content of the story immediately and after a 25 minute delay. He recalled only five of 57 stories with immediate recall, and had similar results for delayed recall (Lecas, Mazaud, & Reibel, 2011).

After getting a baseline assessment of Paul’s language abilities, they could begin the study. The goal was for Paul to learn to translate verbal information into something visual because his visual working memory was much stronger compared to his verbal working memory. Researchers hypothesized that Paul’s visual abilities would overcome the shortcomings of his verbal short-term memory (Lecas, Mazaud, & Reibel, 2011).

For this study, there were 25 excerpts created consisting of 5-6 paragraphs each. 15 of the texts included Disney characters, and the other ten included neutral characters (mother, a cat, etc.) The 15 Disney stories were broken up into three sections: five stories to test rehearsal strategies, five stories for remediation which used a visual recoding strategy and special drawing software, and the remaining five stories were used to test visual recording but without the drawing software. For the neutral stories, five stories determined the baseline performance, and the remaining five were used as a final generalization of Paul’s abilities (Lecas, Mazaud, & Reibel, 2011).

The 25 texts were divided into story units and thematic units. Story units are the words used in the text, and recall of story units indicates the ability to memorize information in the text. Thematic units deal with the themes presented in the story, which indicates skills to connect multiple ideas. Thematic units are a better measurement for comprehension. (Lecas, Mazaud, & Reibel, 2011).

Paul was familiar with the software being used, Disney Interactive 2003. It provides the user with pictures of Disney characters, backgrounds, and accessories; all of the sizes and orientations of these images could be adjusted. A total of 5 tests were administered including two pre-tests, remediation, and a two post-tests. For the first test, Paul listened to ten neutral stories and had to recall them immediately, and after a 15-minute delay. The second pre-test assessed rehearsal and how it affects memorization and comprehension. Paul listened to stories about Disney characters, and was asked to recall the stories immediately and again after a 15-mintue delay. In the remediation test, the experimenter read five new Disney texts to Paul sentence-by-sentence. He would draw each sentence using the computer software, and then the printed drawings were kept out of sight. Paul was asked to recall each drawing immediately and then after a 15-minute delay. The first post-test consisted of five new Disney texts read sentence-by-sentence. Paul was asked to “imagine in his head” the content of the sentences. He then needed to recall the images immediately and after a 15-minute delay. In the second post-test, Paul was presented with five new neutral texts. Paul completed the same procedure as he did in the previous test, as well as the same recall procedures. To score Paul’s performance, the researchers divided each text into story units and thematic units and gave one point for each unit that Paul correctly identified. (Lecas, Mazaud, & Reibel, 2011).

In terms of both story and thematic units, Paul performed significantly better on the immediate recall tests than the delayed recall tests. The pretests gave researchers a baseline for the other tests, as his performance in Pre-test 2 did not improve from Pre-test 1. There was a statistically significant improvement during the remediation and two post-tests. By using the visual recoding methods, Paul retained more information in the form of both story units and thematic units. Additionally, the results for Post-test 1 with Disney characters were similar to Post-test 2 results with neutral characters. Overall, there was a significant improvement in recall from the pre-tests to the post-tests (Lecas, Mazaud, & Reibel, 2011).

Paul was the perfect example to corroborate previous research that there is a dissociation between visual and verbal memory in individuals with Down syndrome (Lecas, Mazaud, & Reibel, 2011). By using drawing tools to engage his visual memory, he was able to close the gap of his verbal memory. Using these tools, Paul retained more information about the texts presented to him, which also increased his comprehension of the material. One possible reason for the improvement is that Paul spent more time creating the drawings, which allowed him to spend more time thinking about each sentence (Lecas, Mazaud, & Reibel, 2011).

There are many benefits and downfalls to this case study. Paul’s results helped researchers to see deep into the mind of one specific person with DS, allowing them to better understand how other DS individuals might be able to improve their reading comprehension skills. However, results from one single case cannot be used to represent an entire population (Lecas, Mazaud, & Reibel, 2011).

Paul allowed researchers to gain knowledge about verbal short-term memory deficits in individuals with Down syndrome, and how it affects text comprehension. The results of the study also found a larger capacity for visual memory. By connecting these pieces of information, text comprehension could be improved using visual recoding strategies. Individuals with DS struggle with reading comprehension among other language abilities, but this can be improved by utilizing visual memory.

Resources

de Graaf, G., & de Graaf, Erik. (2016). Development of self-help, language, and academic skills in persons with down syndrome. Journal of Policy and Practice in Intellectual Disabilities, 13:2, 120-131.

Lecas, J.F., Mazaud, A.M., & Reibel Esther. (2011). Using visual strategies to support verbal comprehension in an adolescent with Down syndrome. Child Language Teaching and Therapy, 27:1, 84-96.

Laws, G., Brown, H., & Main, E. (2016). Reading comprehension in children with Down syndrome. Springer, 29, 21-45.

van Bysterveldt, A.,& Gillon, G. (2014). A descriptive study examining phonological awareness and literacy development in children with down syndrome. Folia Phoniatrica et Logopaedicam 66, 48-57.

Witecy, B., & Penke, M., (2017). Language comprehension in children, adolescents, and adults with Down syndrome. Research in Developmental Disabilities, 62, 184-196.