What is language?
Expression of thoughts as signals & interpretation of those signalsas thoughts
Stages of language comprehension
Hearing & auditory processes →language/code→ concept/message
Stages of speech production
concept/message --> language/code --> motor planning/sequencing --> articulation/execution
Ventral stream
Language comprehension
Dorsal stream
Speech production
What is aphasia?
loss of ability to understand or express speech, caused by brain damage.
What is expressive aphasia? (Broca's)
Speech output is slow & effortful, lacking function words/Problems with grammar & articulation
What do those with expressive aphasia rely on?
Content words: words learned in childhood that are common
What is receptive aphasia (Wernicke's aphasia)?
Fluent speech but meaningless/little understanding of what languageReally is → associated with anosognosia
What is paraphasic speech?
...
What is conduction aphasia?
when the arcuate fasciculus(connection between Wernicke's and Broca's) is broken, cannot connect the two things. difficult to repeat things that are said to you
What is transcortical sensory aphasia?
Able to repeat, but no comprehension
What is transcortical motor aphasia?
Able to repeat, mild problems with comprehension→ associated withRight hemiparesis
What is right hemiparesis?
...
What is global aphasia?
Severe communication difficulties- may be completely non-verbalDifficulty with speech & comprehension
What is transcortical mixed aphasia?
Same as global, but able to repeat
What is anomic aphasia?
Word-finding is severely impaired usually from damage to parietal & or Temporal lobes
What is auditory verbal agnosia: pure word deafness?
Inability to perceive spoken speech→ can perceive non-speech soundsUsually intact speech
What else do we know about aphasias?
Not limited to spoken & written language can be seen in sign language
What are the treatments for aphasia?
Production aphasias do better with rehabilitation therapy than comprehension/speech entertainment therapy
Patient with right hemiparesis who can only smile
Global aphasia
No problem repeating words of understanding speech but is unable to speak fluently
Transcortical motor aphasia
What is dysarthria?
Motor disorder affecting any or all of the 4 subsystems of speech. Respiration, phonation(speech sounds),resonance(airflow), articulation (mouth movement)
Spastic dysarthria
upper motor neuron damage: damage to cortexCauses : cerebral palsy, stroke, or multiple sclerosisSymptoms: harsh, strained voice, vocal pitch breaks, reduced speed of articulation
Flaccid dysarthria
lower motor neuron damageCauses: brainstem stroke, cranial nerve palsy, and myasthenia gravisSymptoms: reduced lip closure, strength of articulation, hyper-nasality, breathy voice
Hypokinetic Dysarthria
Characterized by a rush of rapid speech. This is the type of dysarthria in Parkinson's Disease
Hyperkinetic Dysarthria
Results from damage to basal ganglia (extrapyramidal system). Associated w/ involuntary movements and variable muscle tone. Prosodic disturbances are dominant
Apraxia of speech
Speech disorder-> not associated with muscle weaknessCauses: developed or acquiredSymptoms: difficulty putting sounds and syllables together
Is there a language gene?
KE family-> developmental verbal apraxia, but also other language deficits across half of family->mutation of single gene FOXP2 in affected members
Stuttering
Symptoms: flow of speech is disrupted by involuntary repetition of sounds, syllables, words or phases, and involuntary silent pausesCauses: unknownTherapy: relaxation techniques, singing, choral reading
Cluttering
Symptoms: problems with rate, words confusion, disorganized thoughtsCauses: unknownTherapy: focus on speech details
Spoonerism
Phenomic substitutions Ex:"dear old queen" would turn into "queer old dean
Malapropism
Wrong word substitution
Freudian slips
Error in speech from "unconscious mind"-> mean one thing but say another