By Mrs Abisha, Audiologist & Speech Pathologist, Trichy
Speech sound disorders (SSDs) are communication disorders in which a person has difficulty producing or using speech sounds correctly. These disorders can affect a person’s ability to be understood by others and may impact social, academic, and professional life. SSDs are common in childhood but can persist into adulthood if untreated.
Causes of Speech Sound Disorders
- Developmental delays
- Genetic factors or family history
- Neurological conditions (e.g., cerebral palsy, stroke, brain injury)
- Hearing loss or chronic ear infections
- Structural differences (e.g., cleft palate)
Types of Speech Sound Disorders
Articulation Disorders
Definition: Difficulty producing individual speech sounds due to problems with motor control of the articulators.
Common errors: Substitutions, omissions, distortions, additions.
Phonological Disorders
Definition: Difficulty understanding and using sound rules in speech. Unlike articulation disorders (which focus on individual sounds), phonological disorders involve predictable patterns of errors. The child understands the sound system differently than expected for their age.
Common patterns (Phonological Processes): Final consonant deletion, fronting, stopping, cluster reduction.
Motor-Based Disorders
Childhood Apraxia of Speech (CAS)
Definition: A motor speech disorder where the brain struggles to coordinate muscle movements for speech. CAS affects speech consistency, with difficulty planning and coordinating speech movements, leading to inconsistent errors.
Characteristics: Inconsistent speech errors, difficulty with longer or complex words, groping movements (visible struggle to form sounds), and prosody (rhythm and intonation) issues.
Dysarthria
Definition: A speech disorder caused by muscle weakness due to neurological conditions (e.g., cerebral palsy, stroke, traumatic brain injury).
Characteristics: Slurred or slow speech, weak or breathy voice, difficulty controlling pitch and volume.
