Control Of Cerebral Speech

Question 1

What are the 4 main stages of speech production

Answer 1

Conceptualism
Formulation
Articulation
Self monitoring

Question 2

Conceptualism

Answer 2

Decide what to say

Question 3

Formulation

Answer 3

Select appropriate words and organise in grammatical form

Question 4

Articulation

Answer 4

Plan, co ordinate and initiate movement to produce speech

Question 5

Self monitoring

Answer 5

Auditory and somatosensory feedback for correction

Question 6

What is the left hemisphere specialised for

Answer 6

Phonetic, word and sentence processing

Question 7

Left hemisphere

Answer 7

activated not only by auditory signals but by visual lights with linguistic significance

Question 8

Broca’s area

Answer 8

-early recognition of dominance of left brain hemisphere in speech and language production
-3rd convulsion of the inferior gyrus of the frontal lobe

Question 9

Broca’s aphasia

Answer 9

Brocas aphasia: non fluent & agramattic verbal output, effortful &halting speech. Problems with articulation, word finding, repetition, production, and comprehension of complex sentences.

Question 10

Wernickes area

Answer 10

• Surrounds the posterior part of the lateral fissure, located at the junction of the parietal, temporal and occipital lobes.
• Part of neural system that processes speech sounds and associates sounds with concepts.

Question 11

Wernickes aphasia

Answer 11

Wernicke aphasisa- fluent speech, produced at a normal rate but ‘empty’. Speech content is unintelligible due to frequent errors in word choice/retreiaal. Poor comprehension of language hence no awareness of errors

Question 12

Wernickes model
Visual cortex

Answer 12

Receives written words as visual stimulation

Question 13

Wernickes model
Angular gyrus

Answer 13

Transforms visual representations into an auditory code

Question 14

Wernickes model
Motor cortex

Answer 14

Word is pronounced

Question 15

Respiratory system

Answer 15

• Movement of air in and out of lungs
• Diaphragm, external intercostal and scissors muscles.

Question 16

Phonation (larynx)

Answer 16

• Keep food/liquids out of airways and sound source.
• Muscles stabilise the larynx, control opening/closing of the glottis and tension in vocal folds.

Question 17

Articulation/resonance

Answer 17

• Modification and amplification of sounds
• Tongue, lips, checks, larynx, pharynx, soft palate etc muscles.

Question 18

Dysarthria

Answer 18

• disturbance in speech muscle control due to paralysis, paresis, weakness, slowness
• can affect all speech processes
  -collection of motor speech symptoms that reflect the component of the motor system

Question 19

How many types of dysarthria is there

Answer 19

7

Question 20

Apraxia of speech

Answer 20

• Disturbance in motor planning/ programming of sequential movements for volitional speech production- inability to transform an intact linguistic representation into a coordinate sequence of muscle contraction
• No problem with comprehension and NOT caused by muscle weakness/paralysis.

Question 21

How is apraxia caused

Answer 21

• Caused by lesions to Broca’s area, anterior insular cortex, basal ganglia, supplementary motor area, somatosensory cortex, supramarginal gyrus. Concomitant with aphasia.
• Acquired (TBI, stroke, infections, neuro degeneration) or congenital (childhood apraxia of speech)
• Islands of luent intelligible speech (automatic phrases) interrupted by periods of effortful, off target groping for speech sounds. Low speech rate, hesitation, difficulty initiating speech.

Question 22

Vegetative breathing

Answer 22

• Inspiration> diaphragm + intercostal muscles, 40%
• Expiration> mostly passive, 60%
• Vocal folds (larynx) are abducted:trachea is unobstructed
• Mostly involuntary nervous control (brain stem)

Question 23

Forced breathing

Answer 23

• Phonation is a form of forced breathing requiring voluntary overdoing of vestige respiration.
• Vocal folds adduct> airway constrict > increase in expiratory subglottic pressure> audible vibration
• Frequency and intensity of sound produced determined by subglottic pressure and rate of airflow.

Question 24

Breathing and speech

Answer 24

• Relaxation pressure~pulmonary pressure, thus deep inspiration the subglottic pressure decreases with time
• relaxation pressure is altered via muscle contraction to a subglottic pressure suitable for speech:
  -initially contraction of external intercostal muscles is maintained to counter elastic recoil
  -the contraction of expiratory muscles decrease lung volume

Question 25

What is needed to vibrate the vocal folds

Answer 25

Sustained and increased subglottic pressure needed to vibrate the vocal folds- modifications to vegetative breathing
Inspiration- rapid (10%) and deep
Expiration- slow (90%)and deep