1 Introduction

Schooling in Brazil has been providing more opportunities for access and permanence, and the enrollment of people with disabilities grows every year, adding, in the 2016 Educational Census, 796,486 students with specific needs included in regular schools (^{Instituto Nacional de Estudos e Pesquisas Educacionais [INEP], 2017}). However, the quality of their education is still far below world standards. Data from the last evaluation of the Program for International Student Assessment (PISA), held in 2015, placed Brazil in the 63rd position, in a total of 70 countries involved. 23,141 students from 841 schools participated in this evaluation, representing 73% of the country's 15-year-old students. The results showed a high percentage of students below the level of proficiency established by the Organization for Economic Cooperation and Development (OECD), as necessary for the student to fully exercise his/her citizenship in the areas of Science (56.6%), Reading (50.99) and Mathematics (70.25%) (^{INEP, 2016}).

In order to corroborate this information, data from the Indicador de Alfabetismo Funcional (INAF) - Functional Literacy Indicator -, from 2016, show that a significant percentage of students who are in Brazilian schools, in the initial grades of Elementary School, are illiterate (30%) or in the stage of rudimentary literacy (37%), totaling 67% of functional illiterate students, and in the final grades of Elementary School, 10% of illiterates and 32% with rudimentary literacy, totaling 42% of people with insufficient knowledge to perform simple tasks involving reading and writing of words and phrases after more than 6 years of Elementary School education (^{Ação Educativa & Instituto Paulo Montenegro, 2016}).

It is clear that the schooling has been facing failure in the functional literacy process of its students, and the causes of this breakdown involve many variables. One of them is the lack of psycholinguistic and linguistic knowledge of teachers involved in literacy (^{Luz, 2009}).

Learning to read is a milestone in people's lives. It opens the doors to citizenship, allowing for new learning, and even better possibilities of employment. However, this is not a simple process, and it also implies numerous skills. For the acquisition of our alphabetic system, several skills are required, such as: fine motor coordination, phonological awareness, visuospatial perception, oral language (^{Fonseca, 1995}; ^{Pamplona, 1997}; ^{Capovilla & Capovilla, 2000}; ^{Mousinho, 2003}; ^{Santamaria, Leitão, & Assencio-Ferreira, 2004}; ^{Duinmeijer, De Jong, & Scheper, 2012}).

For subjects with Down syndrome, learning to read is no different, it brings a number of benefits, but it is also a great challenge. Children with Down syndrome present hypotonia in both body and phonoarticulatory organs, which can generate postural instability and inaccuracy in writing movements; difficulty in hearing perception, which leads on to a late development of phonological awareness; delay in the development of oral language, mainly due to problems with operational memory, which make it difficult to internalize new concepts; and the engram of the target sounds of the mother tongue. Therefore, it is assumed that these children present difficulties in acquiring and appropriating the alphabetic system (^{Pacheco & Oliveira, 2011}).

Previous studies have shown that, for all children, the development of phonological awareness and oral language skills, especially with regard to a broadly expressive, organized and semantic-lexical phonological system, provides successful literacy (^{McCartney, 2006}; ^{Dadalto & Goldfeld, 2009}). The results of research confirm that the same occurs in subjects with Down syndrome, and there is a significant positive association between the phonological awareness abilities, the writing hypotheses and the phonological work memory in a Brazilian population of children with Down syndrome (^{Lavra-Pinto & Lamprecht, 2010}). Corroborating these relations, ^{Lavra-Pinto, Segabinazi and Hübner (2014)} emphasized general cognitive ability, expressive and receptive language skills, and phonological awareness as predictors of reading abilities in Down syndrome. And even more specifically about phonological awareness, ^{Lamprecht (1999}, ²⁰⁰⁴⁾ considers that the development of phonological abilities occurs spontaneously between 4 and 6 years of age.

On the other hand, research showed that the training of phonological awareness on individuals with Down syndrome, at least in English language, was not as relevant as a process to favor the learning of written language, especially at a phonemic level (^{Mishra & Stainthorp, 2007}).

Redress proposals in the school - stimulation of the phoneme-grapheme transposition in an alphabetic system of reading and writing learning, with activities at the phonemic, syllabic and supraphonic levels (^{Capellini et al., 2010}) - in workshops, including language activities in general, and specifically phonological awareness, have proved to be efficient as a means of promoting reading in groups with different difficulties (^{Sás, Coser, Villa, Aguiar, & Almeida, 2012}).

Promoting the evolution of these skills through toys means creating a zone of proximal development, since the child will act according to social rules that go beyond his/her age and usual behavior (^{Vygotsky, 1991}). The imaginary situation present in the play develops abstract thinking, and this is possible because it is based on the child's life experience. Since language is the privileged function on the meaning and understanding of what children live in their daily lives, play becomes a fertile field for the experimentation of their daily learning and, in a pleasant way, makes integrating them into their knowledge possible.

Spaces of stimulation and learning of reading and writing go beyond the school, because, when the intervention occurs with children and adolescents with Down syndrome, it may be necessary to make adaptations that reduce the complexity of the task or that minimize the motor requirement, or to include resources that expand the therapeutic and pedagogical scope of the activity.

The main objective of this paper is to compare the evolution, before and after the interdisciplinary stimulation, of the phonological abilities and the understanding of the alphabetical system in children and adolescents with Down syndrome. The present proposal is justified by the few scientific evidences on the favoring of the cognitive-linguistic abilities of this group, especially in Brazil. The central question that moves this research is therefore whether the systematic stimulation of cognitive-linguistic abilities, especially the phonological ones, is able to favor the learning of reading and writing in subjects with Down syndrome.

2 Method

It is proposed a collective case study, that is, an instrumental study extended to several cases. The subjects present in this study the common characteristic of having Down syndrome and difficulties in the process of learning the written language. This option is based on a more in-depth analysis, which favors a better understanding of the phenomenon, and can be seen as a movement towards a generalization (^{Stake, 2000}; ^{Alves-Mazotti, 2006}). The project was approved by the Research Ethics Committee under the number CAAE: 47339615.5.0000.5264.

3 Results

The children participated in the stimulation workshops for one year and evolved skills in alphabet recognition, reading, writing and small text interpretation. Each one of them advanced according to his/her rhythm.

M.E. was able to perform fluent reading of words with simple syllabic structures (consonant-vowel) of up to 4 syllables, such as "PIRULITO" (lollipop), and to perform small interpretations of text with this structure of words. Throughout the workshops, she developed the skills of transposing and manipulating syllables and creating new words, from those presented previously. Her writing followed the same rhythm of reading learning. She improved a lot in behavior, becoming more and more motivated and participatory.

G.S. demonstrated an ability to identify the letters of the alphabet, confusing those who presented similar writing, such as "M/N". She began writing her own name, with visual support, and syllabic reading of simple structure words, with up to 2 syllables.

K.S. evidenced the possibility of identifying the letters of the alphabet, writing her name down, without any visual support, and reading the words with up to 3 syllables, confusing only the sound pairs, due to the difficulty of obtaining auditory feedback, due to the phonological alteration in oral language.

P.F. began writing his own name with visual support and started to recognize all the letters of the alphabet. He continued to present much difficulty in fine motor coordination, which made the writing intelligibility difficult. For better understanding of his writing ability, he used mobile alphabets, boards and loose alphabet letters. He showed great resistance to reading, presenting escape behaviors during many activities. However, when he was able to keep up with his activities, he managed to read loose syllables and dissyllable words with ease.

N.M. began to perform fluent reading of words with simple syllabic structures (consonant-vowel) and some complex (consonant-consonant-vowel), such as "BICICLETA" (bicycle). He performed cursive writing with ease, with small orthographic errors compatible with the level of language. He made small interpretations of text and became more extroverted.

The results of the comparison between the pre-test, before the stimulation workshops, and the post-test, after the children with Down syndrome participated in the intervention proposal, aiming at the development of oral language and, especially, access to comprehension of the alphabetical system, will be presented below.

The results regarding phonological awareness, two different measures for phonological work memory, rapid automated naming, and finally the results in reading a balanced word list, were analyzed.

Table 1 shows that phonological awareness had significant evolution in practically all stimuli, except for synthesis, syllabic segmentation and alliteration.

On the other hand, the comparative results of the phonological work memory between before and after the intervention, now evaluated by the repetition of digits, were also not significant (Table 2).

In the comparison between the pre-test and post-test, when the phonological work memory was measured by the repetition of non-words, the dissyllables revealed statistical significance between the two moments, as shown in Table 3.

Table 4 presents the results for the subtest of Auditive Sequential Memory, called Digit Span (ITPA).

Table 5 shows the means of isolated word readings, classified by type, in the moments before and after the intervention, in which the only significant data was related to the reading of high frequency trisyllables.

4 Discussion

The functional literacy of children in the initial grades of Elementary School has not been an easy task for Brazilian educators (^{INEP, 2016}; ^{Ação Educativa & Instituto Paulo Montenegro, 2016}). The complexity becomes greater when students are children with Down syndrome, who present more compromised linguistic aspects than children with typical development, especially in the field of phonology and morphosyntax, linguistic deficits that interfere in the literacy process (^{Bissoto, 2005}).

A growing number of studies suggest that explicit stimulation of phonological awareness can produce positive effects on both phonological awareness and reading ability in children with and without language difficulties, among them children with Down syndrome (^{Lamprecht, 1999}, ^{2004; Lavra-Pinto & Lamprecht, 2010}; ^{Lavra-Pinto et al., 2014}). And as seen in this study, the constant stimulation of these children, with the support of an interdisciplinary team composed of teachers, psychopedagogues, speech therapists and occupational therapists, will contribute to the literacy process of this group (^{Azevedo, Pinto, & Guerra, 2012}).

The data of the study showed that, in relation to the phonological awareness, there was improvement in all the stimuli, although in syllabic synthesis, syllabic segmentation and alliteration, the data were not significant, probably because of the sample being small. There is a reciprocal relationship between phonological awareness and reading learning, in which larger units usually precede literacy, while phonemic skills are enhanced by the reading experience (^{Zorzi, 2003}). However, it is worth mentioning that, at 4 years of age, the child begins to pay attention to the sounds of words, and gradually develops the phonological awareness. These results demonstrated the potential development (^{Vygotsky, 1991}) of the participants, and how prepared they were for the construction of this learning.

In this research, the simpler skills were less significant, while the rhyme tasks and the more complex ones of syllabic level showed statistical significance between the two moments evaluated. This fact probably favored the process of learning the written language by the children of the group. Likewise, the tasks of the phoneme level presented statistical significance in the comparison between pre-test and post-test, showing that the little experience with reading has already been able to positively impact this ability. These results indicate that, contrary to what ^{Mishra and Stainthorp (2007)} proposed, phonological awareness demonstrated important evolution, through stimulation, in a manner compatible with the gain presented in the learning of written language.

In relation to the evaluation of the phonological work memory, two instruments were used: digit repetition and non-word repetition. The difference between the two moments evaluated was subtle, which confirms a data commonly described in the literature: working memory, in general, is frequently and intensely impaired in intellectual deficits (^{Pereira, Araújo, Ciasca, & Rodrigues, 2015}). However, distinct from the evaluations used, where the stimulus was unique, sometimes with digits, sometimes with non-words, the stimulation of the letter had a broader scope, involving specific cortical analyzers: the name of the letter and its sound processed in the temporal cortex by auditory/semantic analyzers; letter writing involving tactile-kinesthetic stimuli in the parietal cortex and motor areas; and the visual of the letter processed in the occipital cortex. These stimuli are integrated into a posterior associative center, in border zones of superposition between the temporal, postcentral and occipital cortices (^{Luria, 1981}).

The greater the number of significant associations on the same concept, the more easily the creation of the engram is, that is, the storage in the working memory and from this to the long memory, more specifically to the semantic memory (^{Eysenck, 2011}). This explains, in part, why there was improvement in phonemic awareness, although the same did not occur with working memory, given the overlap of the significant stimuli along with the phoneme in question. In other words, the learning of a grapheme includes in its identity a name, a sound (significant) and a form (writing), and it is believed that the integration between these aspects facilitates the internalization of the grapheophonemic transposition. Thus, the presentation of the stimuli worked is highlighted, most of the time, developing phonological awareness with a visual support of the written word.

The item that significantly differentiated the pre and post-intervention moments was the repetition of non-words of two syllables, which favors the retention in memory of small words, most frequently used in literacy processes, and also in the selection of keywords used as the basis for the proposed intervention. Like all learners, early in the process of understanding the alphabetic system, children and young people in this research also began to master regular high frequency words with 2 and 3 syllables (though only the latter were statistically significant). A similar result was described in another study, in which reading of regular words was easier (^{Barby & Guimarães, 2016}).

The selection of words to expand the vocabulary of the book is another successful aspect of the workshops, since they were appropriate for the age group, contained the characteristics mentioned previously and were repeated in the activities, facilitating learning.

Although no data were found in the recent literature to prove the direct relationship between the verbal production of children and young people with Down syndrome and learning to read isolated words, receptive vocabulary markers proved to be good predictors for reading in the research by ^{Hulme et al. (2012)}. The importance of receptive language was also highlighted by ^{Byrne, Macdonald and Buckley (2002)}, who studied aspects of syntax and auditory processing in this population as being associated with reading. A justification for explaining how some people with Down syndrome may be better at reading than at verbal production may be related to their fairly good visual abilities (^{Fowler, Doherty, & Boynton, 1995}).

It is also emphasized that extrinsic factors, such as the supportive therapies to which children have been subjected, and the influence of the family and school environments may have functioned as significant elements towards literacy and advances in phonological awareness.

5 Final consideratons

The data showed that the systematic stimulation of cognitive-linguistic abilities, especially the phonological ones, carried out by an interdisciplinary team, through language stimulation workshops, in group, was able to favor the learning of the reading and writing of children and adolescents with Down syndrome. The diversity of children and young people with Down syndrome (^{Snowling, Nash, & Henderson, 2008}) as well as the reduced sample, can be considered as the limitations of this study.