Cognitive–Behavioral Intervention for Linguistic and Cognitive Skills in Children with Speech and Language Impairments: A Case Report

Abstract

Background: Speech and Language Impairment (SLI) significantly affects children’s communication skills, limiting their social and academic development. Case Information: This single-case study evaluates the effects of a personalized intervention in a 9-year-old child diagnosed with SLI, integrating linguistic and cognitive strategies to remediate core deficits typically observed in children with SLI. Two main objectives were established: (1) to assess the child’s psycholinguistic competencies and cognitive processes and (2) to analyze the impact of the intervention on skills such as phonology, semantics, syntax, executive functions, and emotional well-being. The longitudinal and personalized design included pre- and post-intervention assessments conducted over two and a half years using tools such as the ITPA and Peabody Vocabulary Test. The intervention sessions were structured into linguistic and cognitive activities, with a frequency of two weekly language sessions and one cognitive functions session. Statistical analysis included ANOVA to evaluate significant changes. Conclusions: The results showed significant improvements in linguistic areas such as auditory comprehension (from 3–5 to 10 years) and verbal expression (from 5–10 to 9–6), as well as in cognitive aspects such as visuomotor sequential memory and visual comprehension, which exceeded the expected values for the child’s age. However, skills such as grammatical integration and auditory association did not show significant progress. This demonstrates that personalized and multidisciplinary interventions can considerably improve linguistic and cognitive abilities in children with SLI, although some areas require more specific approaches. The findings highlight implications for designing tailored intervention strategies, emphasizing the need for further research with larger samples and control groups to generalize the results. This case reaffirms the importance of comprehensive approaches in the treatment of SLI to maximize the academic and social development of affected children.

1. Introduction

Speech and Language Impairment (SLI) represents one of the most significant and persistent conditions in childhood communication, affecting the acquisition and effective use of language in the absence of other neurological or sensory deficits. According to L. Leonard (2002), SLI is characterized by notable difficulties in language production and comprehension, which cannot be attributed to brain or sensory development disorders, nor to intellectual deficits. This definition aligns with the DSM-5-TR classification (APA, 2023), which includes SLI under communication disorders, emphasizing persistent problems in all modalities of language, whether written, oral, or sign language.

The impact of SLI on individual development is profound, as the linguistic abilities of those affected are significantly below what is expected for their normative group (Puglisi & Befi-Lopes, 2016). This is due to grammatical and phonological deficits, which are associated with impairments in grammatical processing and short-term phonological memory (L. B. Leonard, 2014), as well as speech perception difficulties—particularly in identifying consonants in noisy environments—indicating a central deficit in feature extraction rather than in basic auditory abilities (Ziegler & Goswami, 2005). On the other hand, SLI negatively affects short-term verbal memory, and performance declines as linguistic load increases. However, this differs from the effects of bilingualism, which mainly impacts vocabulary size (Meir, 2021). Children with SLI inherently exhibit lower levels of receptive vocabulary throughout their development and fail to reach the level of their peers over time, due to factors such as nonverbal IQ and educational background (Rice & Hoffman, 2015). Regarding writing skills, children with SLI score lower on writing tests than their typically developing peers, showing significant deficits in writing quality, grammar, vocabulary, and spelling (Graham et al., 2020), as well as in reading comprehension, which is also affected by deficits in working memory and higher-level language skills such as inference and comprehension monitoring (Cohen, 2004; Wong et al., 2017). All of this results in severe limitations to effective communication, which in turn negatively impacts the individual’s social participation and academic achievement (Marton et al., 2005; St Clair et al., 2011; Westby, 2017).

Given the estimated prevalence of SLI, which affects approximately 7% of preschool-aged children, early identification and targeted interventions are essential. Studies such as those by Botting and Conti-Ramsden (2003), Buiza et al. (2016), Conti-Ramsden et al. (2001), and Girbau and Schwartz (2007) have been fundamental in establishing specific psycholinguistic markers within each domain. These include verbal and phonological memory, phonological awareness and planning, knowledge of morphemes, the formation of linguistic representations, and syntactic comprehension. All of these are evident in the nonword repetition task, which is a strong indicator of SLI, as children with this disorder tend to perform significantly worse than their peers. This makes it an effective tool for identifying SLI due to its high sensitivity and specificity, particularly when children score below the 25th percentile (Conti-Ramsden, 2013). Similarly, the sentence repetition marker has shown high levels of sensitivity (90%) and specificity (85%) in identifying children with SLI, making it one of the most useful tasks for diagnosis (Conti-Ramsden et al., 2001; Redmond, 2011). Additionally, children with SLI often struggle with tasks related to past tense and plural forms, making past tense and plural markers useful for distinguishing them from typically developing children (Conti-Ramsden, 2013; Conti-Ramsden & Hesketh, 2003), as well as with morphosyntactic difficulties, including verb tense marking (Buiza et al., 2016). These markers not only facilitate the detection of potential DLD cases, but also guide intervention strategies to address the specific needs of each child, allowing intervention techniques to be tailored to the individual characteristics of each case (Girbau, 2017; Redmond, 2011).

Moreover, recent advances in research (Rodríguez et al., 2016; Wanicharoen & Boonrod, 2024) have led to a better understanding of how well-targeted interventions can significantly mitigate the challenges associated with SLI, improving the quality of life and the academic and social success opportunities of those affected. The most effective interventions for SLI involve a combination of language therapy (Kambanaros et al., 2017), cognitive and social skills training (O’Handley et al., 2016), and educational support tailored to individual needs (Hubert-Dibon et al., 2016). These interventions not only enhance linguistic and cognitive skills but also foster social participation and reduce stress for both children and their families. Therefore, among the most notable therapies for SLI intervention, syntactic–semantic and semantic therapies have shown significant improvements in the development of verbal argument structure in children with SLI, as both methods help relate arguments to syntax and enhance the use of optional arguments (Ebbels et al., 2017). Music therapy, especially when integrated with speech therapy, has proven effective in improving language components such as phonology, syntax, and morphology, as well as sentence comprehension and memory (Wanicharoen & Boonrod, 2024). Phonological awareness intervention significantly improves phonological awareness itself, reading development, and speech articulation. Metalinguistic and multimodal approaches aimed at improving complex syntax through metalinguistic strategies have been shown to be beneficial for older children with SLI, especially those with reading and writing difficulties (Zwitserlood et al., 2015). Reading process intervention has also been shown to be effective, as the combination of oral language activities with reading skills training improves reading outcomes by addressing lexical, syntactic, and semantic processes (Rodríguez et al., 2016). Finally, social skills interventions that incorporate behavioral strategies can improve pragmatic skills such as nonverbal communication, verbal abilities, and turn-taking in conversations (O’Handley et al., 2016).

This case study explores in detail the manifestation of SLI within an individual context, following the CARE guidelines (Riley et al., 2017), emphasizing the importance of personalized interventions based on rigorous psycholinguistic assessment and a deep understanding of the disorder’s dynamics.

2. Objective

The objectives established in this study were to assess the psycholinguistic competencies of a 9-year-old child diagnosed with SLI, as well as to conduct a cognitive evaluation of linguistic processes. To achieve this, several research hypotheses were proposed. One hypothesis suggested that language intervention would improve linguistic competencies such as phonology, semantics, syntax, and pragmatics. Additionally, another hypothesis proposed that cognitive-level intervention would enhance executive functions and academic, personal, and social performance by improving cognitive competence, motivation, cognitive conditions, academic self-concept, perceived self-efficacy, and psychological well-being.

3. Case Description

The patient, JGG, is a child aged 9 years and 3 months who resides in a town in southern Spain with access to educational, healthcare, and recreational services. He comes from a middle-class family, with both parents employed in stable jobs, ensuring economic and social stability. His nuclear family consists of his parents and an older sister, which fosters social interactions and emotional support within the household. The cultural and social context of the city where he lives, with its Mediterranean climate and strong sense of community, contributes positively to his overall development. He attends a private school near his residence, facilitating his integration into the community. Although he shows an interest in learning, he faces significant difficulties in academic areas related to language, such as reading, writing, and oral expression, which impact his overall performance. His ability to understand verbal instructions and participate in class discussions is limited, but he excels in tasks that do not require advanced linguistic skills, such as mathematics and artistic activities. The school provides support through specialized teachers and adapted pedagogical strategies, promoting his learning progress.

JGG has no relevant family history in areas related to language, learning, or neurological development. Both parents, who hold higher education degrees, report no history of linguistic difficulties, learning disabilities, or neuropsychological problems during childhood or adolescence. His sister and other close relatives have not exhibited delays in language development or conditions such as autism spectrum disorder, intellectual disabilities, or psychiatric disorders. Additionally, no genetic or neurological diseases have been identified in the family that could be associated with the diagnosis.

In October 2019, he was referred to our clinic, where he has been attending uninterrupted weekly language intervention sessions after being evaluated by his school’s psychoeducational team, which detected learning difficulties due to language delay. Currently, this diagnosis has been updated to Speech and Language Impairment (SLI), leading to an expanded intervention plan that now includes cognitive-level therapy once a week.

3.1. Initial Diagnostic Evaluation Process

Following the updated diagnosis of SLI by the psychoeducational team at his school during the 2020/2021 academic year, when JGG was in the second year of primary education, an evaluation of his difficulties was conducted before initiating cognitive intervention. The results obtained from the initial assessment, carried out using the Differential and General Aptitude Battery E1 (BADYG-EI; Yuste et al., 1980), the School Neuropsychological Maturity Questionnaire (CUMANES; Portellano et al., 2012), the Peabody Picture Vocabulary Test (Dunn & Arribas, 2010), and the Illinois Test of Psycholinguistic Abilities (ITPA; Ballesteros & Cordero, 2004), indicate that JGG has very low logical reasoning, with difficulties in analogical relationships, numerical problem-solving, logical matrices, numerical calculation, complex visual orders, rotated figures, immediate memory, and writing alterations.

Additionally, semantic fluency and reading comprehension were found to be at a very low level. Auditory-verbal and image comprehension, phonological fluency, executive function timing, and verbal memory were at a low level. Audio/diagnostic writing, visual memory, and rhythm were at a low-medium level, while visual perception was at a medium level. In terms of vocabulary, his is equivalent to that of a child aged 5 years and 3 months, showing a discrepancy of 21 months from his chronological age, with a verbal IQ of 82.

Regarding his psycholinguistic abilities, there is a significant gap between his chronological age and his auditory and visual comprehension, auditory and visual association, and grammatical and auditory integration. However, motor and verbal expression, visual integration, and auditory sequential memory are almost in line with his age, while visuomotor sequential memory is significantly above expectations. All these findings indicate that his psycholinguistic age is 6 years (72 months), with a 12-month discrepancy from his chronological age of 7 years (84 months).

Additionally, the quantitative data from the standardized test results can be accessed at the following link: [https://doi.org/10.6084/m9.figshare.28330403.v1].

3.2. Differential Diagnosis

SLI is distinguished from other diagnoses according to the DSM-5-TR (APA, 2023). Unlike Intellectual Disability, where language delay is associated with global cognitive limitations, JGG’s non-verbal cognitive abilities fall within the normal range. He also does not meet the criteria for autism spectrum disorder, as SLI presents with typical social development, without deficits in social communication or repetitive behaviors. In hearing disorders, language difficulties stem from primary auditory problems, whereas in SLI, hearing abilities are normal. Finally, SLI does not involve generalized neurological deficits and is exclusively limited to language.

3.3. Comorbidity Analysis

The comorbidity analysis in JGG’s case indicates that he has no relevant medical history or complications in his prenatal, neonatal, or physical development. Although his overall development is within expected limits, previous neuropediatric reports prior to this evaluation revealed cognitive development below his chronological age, with low scores in working memory (5th percentile), verbal comprehension (24th percentile), and perceptual reasoning (13th percentile), and a total IQ of 81, classified as low average (11th percentile).

Emotionally, JGG maintains a positive bond with his family and school environment, displaying sociability and adaptability without signs of emotional disturbances, disruptive behaviors, or emotional regulation problems. Functionally, he has an age-appropriate level of autonomy, performing self-care activities and household tasks with minimal supervision, without presenting motor skill delays that would affect his daily life.

4. Method

4.1. Instruments and Materials

Illinois Test of Psycholinguistic Abilities (ITPA; Ballesteros & Cordero, 2004): The ITPA is an assessment tool for psycholinguistic skills that allows the exploration of different aspects of linguistic processing, such as auditory processing, phonological decoding, and verbal organization. Its Cronbach’s alpha is 0.771.

Peabody Picture Vocabulary Test (Dunn & Arribas, 2010): The Peabody Picture Vocabulary Test is a receptive vocabulary test in which children must select images corresponding to orally presented words. This test is useful for assessing the extent of receptive vocabulary without requiring complex verbal responses, providing an objective measure of children’s lexicon. Its Cronbach’s alpha is 0.641.

4.2. Procedure

To conduct the study, informed consent was first obtained from the child’s parents through a clear and transparent process. Initially, they were invited to a meeting where the study’s purpose, objectives, procedures, and potential benefits and risks were explained. It was emphasized that participation was entirely voluntary and that they could withdraw at any time without consequences. Additionally, data confidentiality and the exclusive use of information for scientific purposes were ensured. Subsequently, a detailed informed consent document was provided, reviewed, and signed after addressing all their questions and ensuring their full understanding.

Following JGG’s initial assessment, a treatment plan was established, with a frequency of two 45 min sessions per week focused on language difficulties, conducted by a speech therapist. Once JGG made progress in oral language, the intervention was expanded to include reading and writing skills, where he also had difficulties. In September 2020, the treatment frequency was increased, introducing two weekly 90 min sessions for oral and written language intervention and one weekly 50 min session targeting cognitive skills, conducted by a psychologist.

From the start of intervention in October 2019 to March 2023, JGG has received a total of 80 sessions of 45 min focused on oral language difficulties, 240 sessions of 90 min addressing both oral and written language, and 120 sessions of 50 min targeting cognitive difficulties. To ensure measurement reliability and fidelity of intervention delivery, all assessments were administered by trained professionals following standardized protocols. Intervention fidelity was monitored through periodic supervision sessions, and scoring was double-checked by independent raters to minimize examiner bias.

4.3. Study Design and Data Analysis

This longitudinal study conducted a pre-post test analysis over 2.5 years and was based on the CARE protocol (Riley et al., 2017) for clinical cases and case studies.

Using SPSS version 29, linguistic and cognitive variables such as auditory and visual comprehension, visuomotor and auditory sequential memory, auditory and visual association, visual, grammatical, and auditory integration, verbal and motor expression, and vocabulary were analyzed. Descriptive analyses were employed to observe the means and standard deviations of the different variables, providing an initial insight into the data and their general behavior.

For comparisons between evaluations conducted at different time points, a repeated measures analysis of variance (ANOVA) was used as the statistical method. This approach allowed for identifying whether there were statistically significant differences between the groups or time points evaluated, determining the statistical significance of the observed changes. The use of ANOVA ensured a robust and appropriate analysis to establish whether variations in the assessments were due to chance or real effects. Although repeated measures ANOVA is typically used in group designs, previous single-case studies have adopted this method to describe within-subject changes across time points. In our case, ANOVA results are interpreted descriptively, emphasizing effect sizes (η²) and trends rather than population-level generalizations.

5. Clinical Intervention

5.1. Intervention in Linguistic Functions

From the linguistic perspective, the intervention focused on the following linguistic objectives (LO), as detailed in the following table (

Table 1. Linguistic Objectives (LO) and Intervention Strategies.

Objective	Intervention
LO 1. Increase vocabulary	Vocabulary expansion and oral expression were developed through interactive games, shared reading, and storytelling activities.
LO 2. Improve oral comprehension	Focused on attention and active listening through activities such as following instructions, answering questions about stories, and listening to audio recordings.
LO 3. Improve auditory association	Reinforced the connection between sounds and words using identification games and songs with gestures.
LO 4. Improve auditory integration	Combined active listening with functional responses through complex instructions and choreographed songs.
LO 5. Improve grammatical integration	Included exercises in sentence construction, sentence completion, and storytelling to enhance grammar skills.
LO 6. Improve auditory sequential memory	Strengthened auditory memory through sequences of sounds and words.
LO 7. Improve verbal expression	Encouraged spontaneous language use through activities such as descriptions, storytelling, and exercises to expand vocabulary and fluency.

):

Prototype activities are available at: [ https://doi.org/10.6084/m9.figshare.28330418.v1].

5.2. Intervention in Cognitive Functions

From the cognitive perspective, the intervention focused on the following cognitive objectives (CO), as detailed in the following table (

Table 2. Cognitive Objectives (CO) and Intervention Strategies.

Objective	Intervention
CO 1. Improve visual comprehension	Worked on attention and visual comprehension using image-word matching games, spot-the-difference activities, and sequencing image tasks.
CO 2. Improve visual association	Encouraged the association between images, words, and concepts through memory games, category classification, puzzles, and logical sequences.
CO 3. Improve visual integration	Integrated visual stimuli with practical tasks such as matching images with words, completing patterns, and classifying objects based on characteristics like shape or color.
CO 4. Improve visuomotor sequential memory	Combined visual sequencing with physical movement through activities such as arranging images in story order, copying patterns, memory-based visual and motor games, and guided writing.
CO 5. Improve motor expression	Addressed motor coordination by integrating body movements through activities such as following gesture sequences, dancing with songs, completing simple obstacle courses, and improving fine motor skills through drawing or modeling.

):

Prototype activities are available at [https://doi.org/10.6084/m9.figshare.28330448.v1].

6. Results

6.1. Expected Results

Following the cognitive and linguistic intervention, improvements with large effect sizes were expected in communication, learning, and social skills. In the linguistic domain, the goal was to increase both receptive and expressive vocabulary and improve sentence structuring skills, including the correct use of grammar, prepositions, and connectors, to foster more fluid and precise communication. In the cognitive domain, improvements were anticipated in working memory, sustained attention, and planning skills, allowing the child to process information more efficiently, follow instructions, and solve problems with greater effectiveness. Additionally, enhanced attention was expected to boost both academic and social performance.

In terms of linguistic development, the intervention aimed to help the child participate in conversations, take turns, adapt to different contexts, and understand nonverbal cues, enriching social interactions. An increase in self-confidence and autonomy was also expected, reducing frustrations and improving self-esteem. Lastly, the anticipated progress would have a positive impact on family and school dynamics, facilitating cooperation, conflict resolution, and a more inclusive environment that supports comprehensive development.

6.2. Obtained Results

Following the intervention targeting linguistic and cognitive skills, the results obtained are presented in

Table 3. Progress According to PEABODY Results (Dunn & Arribas, 2010).

PEABODY	2019 (5:11)	2020 (7:0)	2023 (9:3)	F (η2)
Raw Score	43	55	83	3.23 (0.83) *
IQ	75	82	78	1.88 (0.69) *
Percentile	5	12	13	1.19 (0.61) *
Stanine	2	3	3	0.92 (-)
Equivalent Age	4:5	5:3	7:3	4.37 (0.79) *

* p < 0.05.

and

Table 4. Progress According to ITPA Results (Ballesteros & Cordero, 2004).

ITPA	2019 (6:0)	2020 (7:0)	2023 (9:2)	F (η2)
Auditory Comprehension (AC)	3:5	6:0	10:0	4.32 (0.88) *
Visual Comprehension (VC)	4:5	9:3	10:0	5.01 (0.45) *
Visuomotor Sequential Memory (VSM)	8:11	8:11	10:0	2.89 (0.31) *
Auditory Association (AA)	4:8	5:0	5:4	1.25 (0.12) *
Auditory Sequential Memory (ASM)	4:5	6:9	8:5	4.78 (0.43) *
Visual Association (VA)	5:8	5:8	9:11	3.92 (0.38) *
Visual Integration (VI)	6:6	6:10	7:10	2.43 (0.28) *
Verbal Expression (VE)	5:10	7:4	9:6	5.46 (0.47) *
Grammatical Integration (GI)	3:10	4:4	4:4	0.94 (-)
Motor Expression (ME)	5:0	6:10	10:0	6.12 (0.49) *
Auditory Integration (AI)	6:0	6:0	9:0	3.64 (0.36) *
Composite EPL Score	4:8	6:0	8:8	4.27 (0.40) *

* p < 0.05.

, which illustrate the patient’s progress based on the various reassessments conducted.

6.3. Interpretation of Results

The results from the PEABODY and ITPA assessments reflect notable progress in cognitive and linguistic development between 2019 and 2023, although some challenges remain.

In the PEABODY assessment, the raw score increased significantly from 43 to 83 points (F(2) = 3.23, η² = 0.83, p = 0.003), demonstrating a substantial improvement in receptive linguistic skills. Additionally, the equivalent age increased from 4 years and 5 months in 2019 to 7 years and 3 months in 2023 (F(2) = 4.37, η² = 0.79, p = 0.001), reflecting development that is more aligned with his chronological age. However, IQ and percentile rankings remained in low ranges, fluctuating between percentile 5 (very low) in 2019 and percentile 13 (low) in 2023. These findings suggest that while the child has made absolute progress in specific skills, his relative performance compared to his normative peer group has not significantly improved, highlighting the need for ongoing and targeted interventions.

In the ITPA assessment, improvements with large effect sizes were observed in key areas such as auditory comprehension and verbal expression. Auditory comprehension increased from very low levels in 2019 (3–5) to expected values in 2023 (10) (F(2) = 4.32, η² = 0.88, p = 0.004), while verbal expression showed similar gains, rising from 5–10 to 9–6 over the same period (F(2) = 5.46, η² = 0.47, p = 0.001). Additional notable improvements were observed in auditory sequential memory (F(2) = 4.78, η² = 0.43, p = 0.002), visual association (F(2) = 3.92, η² = 0.38, p = 0.001), and motor expression (F = 6.12, η² = 0.49), reflecting broad enhancements in cognitive and linguistic abilities.

Despite these positive results, some areas, such as grammatical integration, did not show significant changes over time (F(2) = 0.94, with no relevant effect), emphasizing the need to prioritize these aspects in future interventions.

Overall, the data indicate that the child has made considerable progress in receptive and expressive language skills, as well as in memory-related abilities, positively impacting his capacity to communicate and process information. However, the findings also highlight areas for improvement, particularly in his relative performance within normative ranges and in specific skills such as grammatical integration, which require a more targeted approach in future interventions. This general progress suggests that the intervention strategies have been effective, but it remains essential to maintain and refine these approaches to continue enhancing his overall development.

7. Discussion

The results of this single case study reflect significant progress in JGG’s linguistic and cognitive skills following a prolonged and focused intervention. The findings highlight the effectiveness of a comprehensive approach that combines personalized linguistic and cognitive strategies, which is consistent with previous research emphasizing the importance of tailored interventions in SLI (L. Leonard, 2002). This is due to the fact that children with SLI often have diverse and complex needs that require individualized approaches, making customized interventions essential to address specific deficits—such as expressive grammar or pragmatic skills—which can vary greatly among individuals (Ebbels et al., 2017; Pereira et al., 2024; Smith-Lock et al., 2013). Likewise, personalized interventions in SLI—such as pragmatic interventions or those focused on expressive grammar—have demonstrated their effectiveness in various contexts, including school-based programs and individual therapy sessions (De López et al., 2022). In this way, targeted interventions ensure that therapy directly addresses the areas where the child needs the most support, as they can focus on specific domains of language such as vocabulary, morphosyntax, and pragmatics, which are fundamental to overall language development (Nair et al., 2022; Rinaldi et al., 2021; Wright et al., 2018).

In the linguistic domain, the observed improvements in auditory comprehension and verbal expression are particularly notable, shifting from significantly low levels to values closer to the normative group. This translates into an enhanced ability to process and use language in everyday contexts, aligning with studies that link auditory comprehension and verbal fluency with positive functional communication outcomes (Chang et al., 2019). This is because it has been shown that intervention through structured listening activities and the use of varied auditory resources significantly improves listening comprehension and oral fluency, which translates into enhanced communicative skills (Sadiqzade, 2024; Terzioğlu & Kurt, 2022). The limited progress in grammatical integration aligns with studies indicating persistent morphosyntactic deficits in SLI despite intensive therapy (e.g., Lely et al., 2004). Future interventions could incorporate explicit grammar instruction or technology-assisted syntax training, as suggested by Smith-Lock et al. (2013).

In the cognitive domain, the results indicate substantial progress in visuomotor sequential memory, visual association, and visual comprehension, which are critical aspects of academic and social development. These improvements, which exceed the expected values for his age group, underscore the effectiveness of structured activities that stimulate visuomotor integration and visual perception (Van Der Merwe et al., 2023). On the other hand, the lack of improvement in visual integration suggests potential barriers in visuospatial processing that require more specific attention in future interventions. Children with SLI show significant difficulties in remembering patterns and associating them with locations, despite performing similarly to their peers in spatial search tasks. This indicates a specific challenge in integrating visual information rather than a general memory deficit (Bavin et al., 2005). Although they tend to perform poorly on visuospatial working memory tasks (Alt, 2013)—particularly those requiring high attentional control—this is due in part to their reduced capacity for sustained attention (Finneran et al., 2009; Spaulding et al., 2008) and executive functions (Vugs et al., 2017), all of which contribute to their difficulties with visual integration (Hick et al., 2005; Marton, 2008).

The progress in auditory comprehension and verbal expression demonstrates notable development in both receptive and productive language skills, which are often severely impaired in SLI (Alt et al., 2004; Camarata et al., 2009; Mackie et al., 2013). In contrast, the skills that did not show improvement, such as grammatical integration, auditory association, and visual integration, reflect common characteristics of SLI (Lely et al., 2004; Leybaert et al., 2014; Norrix et al., 2007). Compared to a typical case of SLI, JGG presents a mixed profile, suggesting a partial response to the intervention. Typical cases of SLI generally exhibit a more uniform pattern of difficulties across all language domains, whereas JGG has managed to compensate significantly in certain areas while maintaining challenges in others. This profile emphasizes the importance of personalizing interventions based on individual needs, prioritizing areas that still present difficulties, such as grammar, auditory integration, and visual integration. Additionally, this contrast highlights the heterogeneous nature of SLI, where each child may exhibit a unique combination of strengths and challenges, reflecting both brain plasticity and the influence of contextual and biological factors on language development.

The analysis of the Peabody Picture Vocabulary Test and ITPA results reveals discrepancies between absolute progress in specific skills and relative performance within normative ranges. Although absolute improvements were observed, relative performance compared to peers remained below average, indicating that intensive interventions may close skill gaps but not fully bridge developmental disparities. This finding underscores the need for complementary educational support to mitigate long-term academic risks. Although raw scores and equivalent age have improved considerably, IQ and percentile rankings remain low. This finding reinforces the importance of combining approaches that not only enhance absolute linguistic skills but also promote competitive development within the normative peer group. Furthermore, the advances in working memory, sustained attention, and planning skills highlight the importance of incorporating executive functions into intervention programs. These improvements have direct implications for academic and social performance, facilitating active participation in school and family settings (Gathercole et al., 2004). It should be noted that children with SLI are at greater risk of experiencing anxiety and depression (Aloudah, 2024; Conti-Ramsden & Botting, 2008), as they are approximately twice as likely to exhibit internalizing problems (such as anxiety and depression) and externalizing problems (such as ADHD) compared to children with typical language development (Conti-Ramsden, 2013; Yew & O’Kearney, 2013). This is because SLI is also associated with significant socio-emotional challenges, such as recognizing emotions from facial expressions and vocal tones (Taylor et al., 2015), as well as difficulties in peer interactions and social cognition, including problems identifying and labeling emotions (Vissers & Koolen, 2016; Westby, 2017). These challenges stem from their language deficits (Bakopoulou & Dockrell, 2016), although they are more closely related to pragmatic language skills than to expressive or receptive abilities (Conti-Ramsden et al., 2013; St Clair et al., 2011). However, the absence of significant emotional disturbances and the stability of the child’s home and school environments have also been key factors contributing to the success of the intervention. Limitations include the absence of a control group, lack of blinding, and potential placebo effects. Moreover, external factors such as sociocultural background and educational resources may have influenced outcomes. Future studies should incorporate randomized designs, larger samples, and follow-up data to assess the persistence of treatment effects.

Like any research, this study has limitations inherent to single-case designs, such as limited generalizability to a broader population. Although the longitudinal methodology allowed for the evaluation of changes over time, it would be ideal to replicate this approach in a larger sample with control groups. Additionally, the scarcity of specific literature on psycholinguistic skills in SLI highlights the need for further research exploring intervention strategies and their long-term impact. For practitioners, these findings highlight the importance of individualized, multidisciplinary interventions integrating language therapy with cognitive training. Regular progress monitoring and flexible goal-setting appear essential for maximizing gains in both linguistic and cognitive domains.

8. Conclusions

In conclusion, this study underscores the importance of a multidisciplinary and personalized approach in the intervention of SLI, demonstrating significant progress in key linguistic and cognitive skills. Despite the areas that require additional attention, the results provide strong evidence that a well-structured intervention can significantly enhance the quality of life and academic and social development opportunities for children with SLI. These findings emphasize the need for continued research and refinement of intervention strategies to maximize outcomes in this population.