Speech Delay | Autism Navigator Hub

SPEECH AND LANGUAGE DISORDERS

Specific speech and language disorders include a range of conditions in which people have difficulty producing speech sounds, understanding language, or both, without an apparent cause such as hearing loss or intellectual disability.

TYPES OF SPECIFIC DISORDERS OF SPEECH AND LANGUAGE DEVELOPMENT

Speech sound disorders (SSD): problems with the correct articulation of sounds, resulting in incorrect pronunciation.
Language impairment (LI): difficulty understanding (receptive) or using (expressive) language appropriately.
Developmental Language Disorder (DLD): A primary speech impairment with no known medical cause that persists into school age and beyond.
Childhood apraxia of speech (CAS): A motor speech disorder in which children have trouble pronouncing sounds, syllables, and words due to problems with brain signals.
Stuttering: A disorder of speech fluency, such as repetition or prolongation of sounds.

THE ONSET OF SPECIFIC DISORDERS OF SPEECH AND LANGUAGE DEVELOPMENT

These disorders usually become apparent in early childhood, when speech and language skills emerge. Parents may notice delays in toddlerhood, often between 2 and 4 years of age.

CLINICAL MANIFESTATIONS OF SPEECH AND LANGUAGE DEVELOPMENT DISORDERS

Speech sound disorders: incorrect pronunciation of words, difficulty articulating certain sounds.

Language disorders: limited vocabulary, difficulty forming sentences, problems understanding instructions.

Language Development Disorder: Persistent language difficulties that impact academic and social interactions.

Childhood apraxia of speech: inconsistent sound errors, difficulty imitating speech, palpation of jaw movements.

Stuttering: repetition of sounds, prolongations, blocks and visible struggling behavior.

NEUROLOGICAL BASES OF SPEECH AND LANGUAGE DEVELOPMENT DISORDERS

Research shows that these disorders may involve structural and functional abnormalities in specific areas of the brain:

Left supramarginal gyrus: Associated with sensory feedback and integration; abnormalities here may be associated with speech disorders.
Corticostriatal dysfunction: seen in speech development disorders, affecting motor skills and speech processing pathways.

AFFECTED AREAS OF THE BRAIN

Broca's area: Associated with speech production; damage can lead to difficulties with expressive speech.
Wernicke's area: Associated with speech understanding; impairments can cause problems with receptive language.
Arcuate fasciculus: White matter fibers connecting Broca's and Wernicke's areas; damage can result in conduction aphasia affecting repetition and flow of speech.

MAIN CAUSES OF SPEECH AND LANGUAGE DISORDERS

The etiology of such pathologies is multifactorial and includes genetic, environmental, and neurobiological factors. Genetic predisposition, prenatal exposures, and early childhood illnesses may contribute to the development of these disorders.

GENETIC CHANGES
Mutations in the FOXP2 gene may be associated with speech and language disorders, particularly those affecting speech production and comprehension.

ROLE OF INFLAMMATION AND NEUROINFLAMMATION
Recent studies indicate that neuroinflammatory processes may influence the development of speech and language disorders. However, further research is needed to establish a direct link.

ROLE OF CHRONIC AND LATENT INFECTIONS
While some prenatal infections have been associated with developmental delays, the direct impact of chronic or latent infections on specific speech and language disorders remains under investigation.

Nevertheless, emerging studies suggest that certain chronic and latent infections may contribute to the development or exacerbation of speech and language disorders. Although the exact mechanisms are still being studied, several infections have been linked to these impairments:

Mycoplasma pneumoniae infection:
A study using a nationwide longitudinal dataset found a significant association between Mycoplasma pneumoniae infection and an increased incidence of speech and language impairments. The mean latency period from the initial infection to the onset of these disorders was approximately 1.96 years. Notably, children infected before the age of six showed a higher risk of developing subsequent speech and language problems.

Tsai CS, Chen VC, Yang YH, Hung TH, Lu ML, Huang KY, Gossop M. The association between Mycoplasma pneumoniae infection and speech and language impairment: A nationwide population-based study in Taiwan. PLoS One. 2017 Jul 3;12(7):e0180402. doi: 10.1371/journal.pone.0180402. PMID: 28672017; PMCID: PMC5495436.

Group A beta-hemolytic streptococcal (GAS) infection:
Analyses indicate that GAS infections were a major cause of stuttering until the mid-20th century, with improvements coinciding with the introduction of penicillin. This association underscores the potential impact of bacterial infections on speech fluency.

Alm PA. Streptococcal Infection as a Major Historical Cause of Stuttering: Data, Mechanisms, and Current Importance. Front Hum Neurosci. 2020 Nov 9;14:569519. doi: 10.3389/fnhum.2020.569519. PMID: 33304252; PMCID: PMC7693426.

Chronic otitis (middle ear infections):
Persistent or recurrent middle ear infections in early childhood can cause temporary hearing loss, which may disrupt auditory processing and speech development. Research shows that children with a history of chronic otitis media may experience deficits in auditory processing and language skills that persist into later childhood.

Chronic childhood ear infections delay language development: https://news.ufl.edu/2023/12/ear-infection-language-development

Central nervous system (CNS) infections:
Infections directly affecting the CNS, such as encephalitis or meningitis, can lead to acquired speech disorders. These infections may cause inflammation and damage in brain regions critical for speech processing, resulting in difficulties with comprehension and expressive abilities.

Rofes, A., van de Beek, D., & Miceli, G. (2021). Language impairments and CNS infections: a review. Aphasiology, 36(10), 1206–1248. https://doi.org/10.1080/02687038.2021.1937922

Conclusion
Understanding these associations is crucial for developing targeted interventions and preventive strategies

THE ROLE OF THE IMMUNE SYSTEM IN SPEECH AND LANGUAGE DISORDERS

Some research suggests that immune system disorders may play a role in neurodevelopmental disorders, potentially affecting speech and language development.

INFLUENCE OF THE MICROBIOME IN SPEECH AND LANGUAGE DISORDERS

The gut-brain axis is a growing area of interest, with research exploring how gut microbiota may influence neurological development and function, possibly influencing speech and language outcomes.

DISORDERS OF ENDOCRINE SYSTEM REGULATION IN SPEECH AND LANGUAGE DEVELOPMENT DISORDERS

Hormonal imbalances, such as thyroid hormone deficiency, can affect brain development and may contribute to problems with language acquisition.

METABOLIC SYSTEM DYSREGULATION IN SPEECH AND LANGUAGE DISORDERS

Interventions are typically interdisciplinary and include:
Speech therapy: Individual exercises to improve articulation, speech comprehension and expression.
Occupational therapy: assistance in developing fine motor skills that support speech, such as oral motor exercises.
Behavioural interventions: methods for working with associated behaviour and improving communication skills.

ANTI-INFLAMMATORY AND ANTI-INFECTIOUS THERAPY

There is currently limited evidence to support the use of anti-inflammatory or anti-infective treatments specifically for speech and language disorders. Most therapeutic approaches focus on behavioral and educational interventions.

However, new research suggests that anti-inflammatory and anti-infective treatments may have a role in treating certain speech and language disorders, particularly when these disorders are associated with underlying inflammatory processes or infections.

ANTI-INFLAMMATORY METHODS:

Studies have examined the use of various anti-inflammatory agents to treat the core symptoms of neurodevelopmental disorders, which often include speech and language impairment. A narrative review highlighted several agents:

Prednisolone: a corticosteroid with potential benefits in reducing stereotypic behavior.
Celecoxib: A nonsteroidal anti-inflammatory drug (NSAID) that may relieve irritability and hyperactivity.
Omega-3 fatty acids: Known for their anti-inflammatory properties, they have been linked to reduced lethargy and hyperactivity.

The mechanisms by which these agents exert their effects are not fully understood, but may involve suppression of microglial activation and modulation of immune cell imbalances, leading to reduced levels of proinflammatory cytokines in the brain.

Arteaga-Henríquez G, Gisbert L, Ramos-Quiroga JA. Immunoregulatory and/or Anti-inflammatory Agents for the Management of Core and Associated Symptoms in Individuals with Autism Spectrum Disorder: A Narrative Review of Randomized,

Placebo-Controlled Trials. CNS Drugs. 2023 Mar;37(3):215-229. doi:10.1007/s40263-023-00993-x. Epub 2023 Mar 13. PMID: 36913130; PMCID: PMC10024667.

ANTI-INFECTIOUS DRUGS:

In cases where speech and language disorders are associated with infections, antimicrobial treatments have been considered:

Antibiotic therapy for Lyme disease: Some children diagnosed with Lyme disease and ASD show improvements in speech and communication after long-term antibiotic therapy. A study found that after six months of antibiotic therapy, participants showed significant improvements in speech and language skills.

Kuhn M, Grave S, Bransfield R, Harris S. Long term antibiotic therapy may be an effective treatment for children co-morbid with Lyme disease and autism spectrum disorder. Med Hypotheses. 2012 May;78(5):606-15. doi: 10.1016/j.mehy.2012.01.037. Epub 2012 Feb 22. PMID: 22361005

Treatment of otitis: Chronic middle ear infections can lead to hearing loss, which subsequently affects speech and language development. To prevent these complications, appropriate antibiotic treatment for otitis media is necessary.

KALYANAKRISHNAN RAMAKRISHNAN, MD, FRCSE, RHONDA A. SPARKS, MD, AND WAYNE E. BERRYHILL, MD. Diagnosis and Treatment of Otitis Media. Am Fam Physician. 2007;76(11):1650-1658. https://www.aafp.org/pubs/afp/issues/2007/1201/p1650.html

CONSIDERATIONS AND FUTURE DIRECTIONS

While these results are promising, it is important to approach anti-inflammatory and anti-infective treatments with caution:

Individualized assessment: Not all speech and language disorders have an inflammatory or infectious etiology. A thorough medical examination is necessary to identify the underlying causes before initiating such treatment.
Potential side effects: Long-term use of anti-inflammatory drugs and antibiotics may have side effects.
Need for Further Research: Larger, controlled studies are needed to establish the effectiveness and safety of these treatments specifically for speech and language disorders.

In conclusion, while anti-inflammatory and anti-infective treatments offer potential for treating certain speech and language disorders, their use must be based on careful diagnosis and consideration of individual patient factors.

Collaboration between professionals, including speech therapists and physicians, is essential to developing comprehensive and effective treatment plans.