Lecture 8 Flashcards
What is language?
- a set of symbols and a set of rules
- Crossed across two types of modality and activity divided into either expressive or receptive
What are the 4 language functions?
- Auditory-verbal comprehension
- Speech: auditory expressive
- Reading: visual receptive
- Writing: visual expressive
How do we understand the brain regions involved in language?
- from the studies of stroke victims and brain imaging of normal individuals (PET or fMRI)
What is Broca’s aphasia?
- also known as expressive aphasia/non-fluent aphasia
- results from damage to the interior left frontal lobe
- issues with speech production
What are the symptoms of Broca’s aphasia?
- slow and laborious speech
- person can mostly comprehend the speech of others, but not fully
- impaired in speaking, but can still comprehend
What is the anatomical basis for Broca’s aphasia?
- damage in inferior frontal lobe
- Need to have damage beyond the cortex
- need to have damage in the white matter (the myelin sheath) - damage to the caudate nucleus in basal ganglia can also produce this aphasia
What is wernicke’s aphasia?
- issues with speech comprehension
- receptive or fluent aphasia
- principally an impairment in comprehension
What are the symptoms of wernicke’s aphasia?
- poor speech comprehensions
- fluent, but meaningless speech
- patients are unaware of their comprehension deficit
What is the anatomical basis for Wernicke’s aphasia? (neuropsych functioning)
- auditory association cortex of posterior superior temporal gyrus (recognizes sounds and words)
What is prosody?
- refers to variations in rhythm, pitch, and cadence that communicate information
- used to distinguish questions from statements
- prosody can communicate cues from statements
What is the anatomical basis for prosody?
- not disrupted for Wernicke’s
- disrupted damage to the right hemisphere
In what hemisphere is prosody mediated by?
- The right hemisphere
Which aphasia is disrupted by prosody?
- Broca’s lesions disrupt prosody because of the labor and disruption of speech
What is Pure alexia?
- refers to inability to read or alexia without agraphia
- writing is not impaired
- similar to word deafness
How is pure alexia produced?
- damage to the left visual cortex AND posterior end of the corpus callosum.