Speech Disorders

any condition that affects a person's ability to produce sounds that create words

Childhood Apraxia of Speech (CAS)

Key Concepts:

• CAS is a motor speech disorder present from childhood.

• It involves difficulty planning/programming movements for speech.

• Speech sounds inconsistent, with errors in intonation and stress.

• Children may have normal non-speech motor skills (e.g., walking), but severe speech delays.

Characteristics:

• Vowel errors (e.g., says “tat” instead of “tot”)

• Inconsistent sound production (e.g., says “banana” three different ways)

• Groping movements (child trying hard to find the right mouth posture)

Acquired Apraxia of Speech (AOS)

Key Concepts:

• Caused by stroke or brain injury affecting Broca’s area.

• Errors in speech sound placement and prosody.

• Often co-occurs with Broca’s aphasia.

Characteristics:

• Slow speech

• Groping for sounds

• Distorted consonants

• Monotone voice

Dysarthria

Key Concepts:

• Dysarthria = weakness, paralysis, or incoordination of speech muscles.

• More common in children with cerebral palsy.

• Adults get it from stroke or neurodegenerative diseases.

Symptoms:

• Slurred speech

• Slow or fast rate

• Breathy or harsh voice

• Imprecise articulation

Cerebral Palsy

A group of disorders affecting movement and muscle tone, often caused by brain damage before or during birth, leading to varying degrees of motor impairment.

Types by limb involvement:

• Monoplegia: One limb

• Paraplegia: Both legs

• Triplegia: Three limbs

• Quadriplegia: All four limbs

By muscle tone:

• Spasticity (stiffness)

• Hypertonicity (too much tone)

• Muscle atrophy (wasting)

Ataxic CP and Severity Levels

Ataxic CP involves poor muscle coordination and balance, impacting the ability to perform precise movements. Severity can differ from mild limitations to significant disabilities that affect daily activities.

Ataxic CP:

• Cerebellar damage → poor coordination.

• Movements are jerky, unsteady.

• Speech = irregular rhythm, errors in timing.

Severity Levels (Table 9-1):

• Mild: Independent, speech OK

• Moderate: Needs help, speech affected

• Severe: Full assistance, speech very limited

Reflexes and Motor Development

Abnormal Reflexes in CP:

• Interfere with walking, talking, eating

• E.g., Moro reflex, ATNR (asymmetric tonic neck reflex)

Motor Delay:

• CP kids struggle with sitting, standing, walking

• Reflexes don't disappear normally

Speech Subsystems in CP

Respiration: Poor breath control → short phrases
Phonation: Strangled or breathy voice
Resonance: Hypernasality from weak soft palate
Articulation: Jaw/tongue problems → unclear sounds
Prosody: Monotone, flat speech, short utterances

Speech Development & Acquired Dysarthria In CP

In CP:

• Voiced consonants (e.g., /b/, /d/) harder than voiceless

• Speech errors continue into adulthood

Acquired Dysarthria:

• Affects adults with stroke, MS, ALS

• Speech was normal before disorder onset

Acquired Dysarthria Types

Flaccid: LMN damage (e.g., Myasthenia Gravis) – breathy, weak voice
Spastic: UMN damage – strained, slow speech
Ataxic: Cerebellum – irregular prosody
Hypokinetic: Parkinson’s – fast, low volume, monotone
Hyperkinetic: Huntington’s – sudden changes, irregular rate
Mixed: MS, ALS – mixed symptoms

Spastic and Ataxic Dysarthria

Spastic Dysarthria:

• Harsh voice

• Imprecise articulation

• Short phrases

Ataxic Dysarthria:

• Cerebellar damage

• Speech sounds like it's drunk or offbeat

• Irregular stress and rhythm

Hyperkinetic & Mixed Dysarthria

• Hyperkinetic: Involuntary movement disorders (e.g., Huntington's). Breathy or strangled voice, inconsistent speech.

• Mixed Dysarthria: ALS or MS (multiple areas affected). Symptoms vary.

Assessment – Speech Mechanism

• Respiration test: Straw bubbling underwater test

• Laryngeal function: Prolonged vowels to assess breathiness/harshness

• Articulators: Tongue, jaw, lips → check symmetry and coordination

• Velopharyngeal check: Look for nasal emission & hypernasality

Speech Intelligibility & Treatment Team

• Intelligibility Test: Sentence-level better than word-level.

• Team members: SLP, OT, PT, physicians, educators.

• Early treatment focus: Reduce spasticity, improve positioning.

Treatment Strategies for CP kids

• For CP kids: Focus on respiration → then speech

• For adults: Exaggerated articulation (e.g., LSVT Loud for Parkinson’s)

• Tips:

  • Use gestures, slow rate

  • Practice clear word stress

  • Use AAC if needed