CSD 2230HUMAN COMMUNICATION

DISORDERS

Topic 7Speech Disorders

Motor Speech Disorders

Motor or Neurogenic Speech Disorders

Speech difficulties that are related to problems of movement as a result of some neurological disorder or injury

Heterogeneous Affect the planning, coordination,

timing, and execution of speech movements

May affect phonation, resonation, and articulation

Major Types of Neurogenic Impairment

1. Cerebral Palsy2. Dysarthria of speech3. Apraxia of speech

Cerebral Palsy

Heterogenous group of neurological disorders that result in difficulty with motor movements

Acquired shortly before, during, or after birth

Developmental disorder Continuum of physical

manifestations

DysarthriaGroup of related speech impairment that

result from disturbed muscular control caused by damage to the mature nervous system

Acquired disorder May affect respiration, phonation,

resonation, and/or articulation Speech characteristics include slow or rapid

motor function, decrease in the range or strength of motor skills, poor directionality or motor timing

Apraxia

Affects the phonological selection and sequencing of speech sounds and articulation

Acquired disorder Affects the ability to organize,

plan, and execute the movement of speech muscles

What Causes Motor Speech Disorders?

Stroke Traumatic brain injury (TBI) Anoxia Neoplasms Infections and toxins Acquired diseases

Cerebral Palsy

A group of nonprogressive neurological difficulties resulting from brain injury very early in life

Areas affected include motor movement, communication, growth and development, locomotion, learning, and sensation

Incidence is 1.5-3/1000 births Primary characteristics

A developmental neurogenic disorder that results from abnormal brain function

It’s not a disease Predictable motor patterns

Types of Cerebral Palsy

1. Spastic (hypertonia)Characterized by too much muscle tone

2. Athetoid (dyskinesia)Characterized by slow involuntary

movements

3. AtaxicCharacterized by uncoordinated

movements

Spastic Cerebral Palsy

60% of individuals with cerebral palsy

Motor movements are jerky, labored, and slow

Infantile reflex patterns

Athetoid Cerebral Palsy

30% of individuals with cerebral palsy

Slow involuntary writhing Infantile reflex patterns

Ataxic Cerebral Palsy

10% of individuals with cerebral palsy

Uncoordinated movements Disturbed balance which is

especially noticeable in their gait Damage is to the cerebellum

Motor and Motor Speech Characteristics

with Cerebral Palsy Speech isn’t always affected and

varies somewhat with the type of CP When speech is affected, all aspects

of speech production may be affected including respiration, phonation, resonation, articulation, and prosody

CD-ROM Ch.14.02 shows a speaker with spastic CP talking about sports. How much can you understand?

Motor and Motor Speech Characteristics

with Cerebral PalsyOther issues related to cerebral palsy:

Breathing problems Rigidity Velopharyngeal incompetency Uncoordinated articulator movements Intellectual processing Auditory processing Language impairments

Intervention might include augmentative and alternative communication systems

CD-ROM Ch14.03 illustrates conversation with such a device

The Dysarthrias A group of impairments that may

affect the speed, range, direction, strength, and timing of motor movements

Results from paralysis, weakness, or discoordination of speech muscles

Not a language disorder but rather a difficulty in motor speech control

Types and Associated Etiologies

Flaccid dysarthria Characterized by hypotonia (weak muscle

tone) which results in weakness or paralysis of the affected muscle

Speech characteristics include shallow breathing, breathy voice, aphonia (no voice), reduced pitch and loudness, monotone, hypernasality, and imprecise articulation

Etiologies include Bell’s Palsy, myasthenia gravis, and muscular dystrophy

Audio examples of flaccid dysarthria

Types and Associated Etiologies

Spastic dysarthria Characterized by hypertonia (stiff and rigid

muscles) commonly caused by stroke Speech movements are difficult and

speech is characterized as slow with jerky, imprecise articulation and reduction in the rapidly alternating movements of speech

Audio examples of spastic dysarthria

Types and Associated Etiologies

Ataxic dysarthria Characterized by a combination of

hypotonia (reduced tone) and ataxia resulting in problems in the accuracy, timing, and direction of movement

Speech movements are jerky and imprecise

Audio examples of ataxic dysarthria

Types and Associated Etiologies

Hypokinetic Dysarthria Characterized by hypokinesis (decreased

movement) Parkinson’s disease results in a good

example of this kind of dysarthriaProgressive disorder where the muscles become

rigid, resulting in reduced motor movements, involuntary shaking or tremors, slowness of movement, and difficulty initiating voluntary movements

Audio examples of hypokinetic dysarthria from Parkinson’s

Types and Associated Etiologies

Hyperkinetic dysarthria Characterized by hyperkinesia

(increased movements) in the form of involuntary tremors and tics

Major speech characteristic is imprecise articulation

Dystonia and chorea provide examples Audio examples of hyperkinetic

dysarthria from dystonia and chorea

Types and Associated Etiologies

Mixed dysarthria Caused by diffuse brain damage ALS provides a good example of

mixed dysarthria Audio examples of mixed

dysarthria from ALS

Apraxia

Disorder of motor placement and sequencing that’s unrelated to muscle weakness, slowness, or paralysis

When speech muscle groups are affected, it is called apraxia of speech

Speech difficulties are not the result of muscle weakness or slowness (dysarthria) or of linguistic processing (aphasia)

Almost always due to damage to Broca’s area in the cortex

Characteristics of Apraxia of Speech

Groping attempts to find the correct articulatory position

Frequent articulation errors Self-correcting behaviors Variable in their abilities Audio example apraxia of speech