L29: Speech & Language Flashcards
What does speech require?
precise neuromuscular coordination of respiration, phonation, resonance & articulation systems.
What are the 4 processes of speech?
1) respiration: breathing provides power
2) phonation: production of sound by muscle contraction
3) articulation: formation of recognizable speech by the mouth
4) resonation: sound quality shaped by throat
What are the 5 dimensions of language?
1) phonology -rules determining how sounds can be sequenced
2) morphology -rules for meaning of sounds
3) syntax -rules for a language’s grammar
4) semantics -rules for the meaning of words
5) pragmatics -rules for communication (prosody, gestures, intonation)
Define prosody
“melody of language” -pitch changes that convey emotions as well as linguistic info
Broca’s area is in posterior aspect of inferior frontal gyrus (areas 44 & 45). Explain in more details what these areas 44 & 45 do.
Area 44 (posterior part of inferior frontal gyrus): involves in phonological processing & in language production, and is near face representations in cortical motor areas so controls mouth & tongue.
Area 45 (anterior part of inferior frontal gyrus): involved in semantics & plays a role in verbal memory.
Wernicke’s area is formed by planum temporale of temporal lobe and supramarginal gyrus of parietal lobe. What is the general function of this area? Also, it is comprised of multiple functional subregions. Explain these 3 subregions.
General function is thought to relate to the representation of phonetic sequences, regardless whether the individual hears them, generates them himself or herself, or recalls them from memory.
It is comprised of 3 functional subregions:
1) responds to spoken words (including the individual’s own words) & other sounds
2) responds only to words spoken by someone else but is also activated by recall of a list of words
3) more associated with producing speech than perceiving it.
The inferior parietal lobule is called the language processing node, and is composed of which 2 gyri?
1) angular gyrus –> semantic processing in both R & L hemispheres
2) supramarginal gyrus –> involved in phonological & articulatory processing of words.
What areas of our brain are activated when understanding similar sounding and meaning words?
1) homonyms (wait vs weight) –> left hemisphere posterior central sulcus & inferior frontal gyrus are involved
2) synonyms (ship vs boat) –> broader regions in the inferior temporal & frontal lobes.
Are subcortical areas (cerebellum, basal ganglia, limbic system) involved in speech?
Yes
What are the 3 types of speech impairments?
1) articulation disorders -distortions, substitutions, omissions, addition
2) fluency disorders -stuttering & cluttering
3) voice disorders -voice sounds breathy, hoarse, husky, or strained.
Broca’s aphasia vs Wernicke’s aphasia
Brocas
- halting speech
- repetitive
- disordered syntax, grammar, and structure
- comprehension intact
Wernickes
- fluent speech
- little repetitions
- syntax & grammar adequate
- contrived or inappropriate words
- comprehension intact
What is global aphasia?
- both expressive & receptive aphasia
- poor prognosis
- extensive damage to frontal, temporal & parietal cortices
What is conduction aphasia?
- normal language comprehension & normal spontaneous oral expression
- problems with expression (mix up sounds in words, omit words)
- destruction of arcuate fasiculus
What is anomic aphasia?
- difficulty in finding certain words
- often caused by damage in parietal lobe around angular gyrus
- “can’t name things”
What is anarthria?
-ppl can’t articulate words that would convey their thoughts (loss of ability to speak coherently)
What is alexia?
-can’t read but can write due to damage to inferior part of left occipital & temporal lobes
Alexia vs dyslexia
alexia is an acquired injury or disorder in adult life where people can’t read but can write
dyslexia is a developmental problem in children presenting with various degrees of difficulty in learning to read and write.
What are some causes of communication disorders?
- trauma
- vascular disturbance
- tumor/infection
- environment (nutritional deficiency)
- neurodegeneration (Parkinson’s, alcoholism
- genetic
- idiopathic (autism)
We’ve learned that the dominant hemisphere, which is commonly the left hemisphere is involved in language. Does the right hemisphere play a role in language?
-it has been seen that damage in the right hemisphere can lead to communication deficits involving the interpretation of contex, such as direct and indirect context disorders.
Indirect context disorders: difficulties interacting with your environment (hemineglect of left side & anosognosia -unawareness of such deficits)
Direct context disorders (aka pragmatic communication disorders): affect communication & cognition directly; disorders of prosody, discourse organization and comprehension of body language
What is the WADA test?
- you paralyze one hemisphere to study effects of non-dominant hemisphere on language
- discovered that both hemispheres play a role in language
What is socioeconomic status have on communication?
It has been shown that brain can change rapidly in response to enrichment (increased fractional anisotropy (FA) in white matter, which reflects more fiber density, axonal diameter & myelination). Higher socioeconomic status (better nutrition, more access to books, etc) is associated with higher levels of Broca’s activation.
What is the effect of alcohol on broca’s area?
continued alcohol use has a profound effect on language areas by decreasing broca’s area.
What is Velocardiofacial (VCFS) syndrome?
It is the 2nd most common genetic syndrome after down syndrome due to loss of 1 copy of 22q11.21. People will have elongated nose, almond-shaped eyes, slight chin. There are more than 150 traits associated with VCFS syndrome, such as alteration of facial appearance, cleft palate, speech problems, feeding problems, heart problems, learning & language deficits, middle ear infections, hypothyroidism (leading to seizures), immune system problems, and 1/3 of VCFS children have autism.
what is the #1 cause of tetralogy of fallot (a heart condition)?
VCFS syndrome which is the 2nd most common after down syndrome.
