Download - Language & Speech
Language & SpeechLanguage & Speech
June 21, 2011
Review QuizReview Quiz
1. Provide evidence for or against the role of vaccines in autism.
2. Explain the formation of the notochord and/or neural tube, and why this stage of development is important.
3. Describe the major regions (i.e., the structures you modeled with clay yesterday) of the brain and their formation.
DiscussionDiscussion
What is Language?Why Do We Use Speech &
Language?Are Speech & Language Unique to
Humans?
Create Your Own LanguageCreate Your Own Language
RadioLab PodcastRadioLab Podcast
Words, Part 1
Wernicke’s & Broca’s AreaWernicke’s & Broca’s Area
http://www.britannica.com/EBchecked/media/3601/Lateral-surface-of-left-hemisphere-of-brain
Language LateralizationLanguage Lateralization
Areas important to language are primarily located on the left side of the brain.
This is determined using the Wada test.– Anesthetic is injected into one carotid artery to
anesthetize one cerebral hemisphere.
– If language is located here, the person will lose the ability to talk.
The left hemisphere is dominant for speech in approximately 95% of all right-handed people!
So Then, the Right Hemisphere Has So Then, the Right Hemisphere Has No Role in Speech.No Role in Speech.
There is some involvement of the right hemisphere, even though the left hemisphere is dominant.
For example, the right hemisphere is important:– Describing spatial information (maps, etc)– Forming a story– Prosody (melodical rhythm and stresses of
speech)
An Interesting Exception: An Interesting Exception: Case J.M.Case J.M. 16 y.o. white female 8th grade level in self-paced special education
classes No movement on right side of body Cranial deformities & extra bone in skull Left hemisphere hypoplasia diagnosed at age
8– Left frontal lobe missing, area occupied by fluid-
filled cyst– Decreased vasculature on left temporal, parietal,
and occipital lobes
From Lecture by Anthony Y. Stringer, Emory University , 2006
From Lecture by Anthony Y. Stringer, Emory University , 2006
J.M.’s Brain ScanJ.M.’s Brain Scan
Normal Angiogram of Normal Angiogram of J.M.’s Right HemisphereJ.M.’s Right Hemisphere
Angiogram Showing Agenesis
of J.M.’s Left Middle Cerebral Artery
From Lecture by Anthony Y. Stringer, Emory University , 2006
J.M.’s AngiogramsJ.M.’s Angiograms
Boston Diagnostic Aphasia Exam
Repetition
Fluency
Word Discrimination
Complex Comprehension
Responsive Naming
Confrontation Naming
Reading
%ile
70
96
87
85
87
100
90
Kaplan Sentence Arrangement Test 60%
From Lecture by Anthony Y. Stringer, Emory University , 2006
J.M.’s Language ResultsJ.M.’s Language Results
Right Hemisphere and LanguageRight Hemisphere and Language
May take on many language functions in response to severe left hemisphere developmental trauma– Early intractable
epilepsy– Hemisphere
agenesis/hypoplasia– Early left
hemispherectomy But, this comes at a
cost…
From Lecture by Anthony Y. Stringer, Emory University , 2006
Broca’s AphasiaBroca’s Aphasia
Results from damage to Broca’s area and surrounding areas in the left inferior frontal lobe
Slow, labored speech with great difficulty producing words
http://faculty.washington.edu/chudler/functional.html
Role of Broca’s Area in SpeechRole of Broca’s Area in Speech
May be responsible for memories of the motor muscle sequences needed for forming words
Thus, deficits are of 3 types:– Agrammatism: difficulty with grammar– Anomia: difficulty finding a word– Articulation: difficulty pronouncing
words
Difficulties in Broca’s AphasiaDifficulties in Broca’s Aphasia
Meaning of words is correct, but difficult to pronounce– Emphasis on content words, difficulty with function words
Find it much easier to understand speech than to produce it
“kid…kk…can…candy…cookie…candy…well I don’t know but it’s writ…easy does it…slam…early…fall…men…many no…girl. Dishes…soap…soap…water…water…falling pah that’s all…dish…that’s all.”
Physiology of Behavior. 7th edition.
Carlson, N.R.
Needham Heights (MA): Allyn and Bacon; 2001.
Other Regions in Broca's Other Regions in Broca's AphasiaAphasia Left Precentral Gyrus of the Insula
– When damaged, see apraxia (impaired ability to move tongue, lips, and throat)
Periaqueductal Gray of the midbrain– When damaged, see disruptions in
vocalization, even to the extent of mutism
Neocortical damage in the frontal lobe Cerebellum
Wernicke’s AphasiaWernicke’s Aphasia
Results from damage to Wernicke's area in the auditory association cortex on the left temporal lobe
Leads to difficulties in comprehending words and producing meaningful speech
Speech fluidity is maintained
http://faculty.washington.edu/chudler/functional.html
How Does Wernicke’s Aphasia How Does Wernicke’s Aphasia Sound?Sound? “Never, no mista oyge I wann tell you this
happened when happened when he rent. His—his kell come down here and is—he got ren something. It happened. In thesse ropiers were with him for hi—is friend—like was. And it just happened so I don’t know, he did not bring around anything. And he did not pay it. And he roden all o these arranjen from the pedis on from iss pescid. In these floors now and so. He hadn’t had em round here.”
Kertesz, 1981, p. 73
Physiology of Behavior. 7th edition.
Carlson, N.R.
Needham Heights (MA): Allyn and Bacon; 2001.
Wernicke’s ComprehensionWernicke’s Comprehension
When asked to use nonverbal cues to respond to questions, responses of patients reveal that they do not comprehend the question.
They are often unaware of their deficits. Receptive aphasia
– Wernicke’s area contains memories of sequences of sounds that make up words
Difficulties in Wernicke’s AphasiaDifficulties in Wernicke’s Aphasia
Recognition:– Pure word deafness, the inability to
understand a word even when it is heard Comprehension:
– Transcortical sensory aphasia, damage to posterior language areas affects the ability to understand words even when recognized
Repetition:– Conduction aphasia, poor repetition even
when speech is fluent and meaningful
Other Regions in Wernicke’s Other Regions in Wernicke’s AphasiaAphasia Primary auditory cortex
– Interruption of delivery to Wernicke’s area– Damage causes pure word blindness
Posterior Language Area– Region located near the junction of the
temporal, occipital, and parietal lobes– Damage causes transcortical sensory aphasia
Arcuate Fasciculus– Axon passage between Wernicke’s area and
Broca’s area– Damage causes conduction aphasia
Aphasia SubtypesAphasia SubtypesSubtype Fluency Repetition Comprehension
Perisylvian: Broca’s (Motor)
- - +Transcortical: Motor - + +Perisylvian:
Wernicke’s (Sensory)+ - -
Transcortical: Sensory + + -Perisylvian: Conduction + - +Perisylvian: Global - - -Transcortical: Mixed - + -
From Lecture by Anthony Y. Stringer, Emory University , 2006
Voices of AphasiaVoices of Aphasia
Coloring DiagramsColoring Diagrams
RadioLab PodcastRadioLab Podcast
Words, Part 2
BrainstormingBrainstorming
What other factors affect our use of speech and language?
McGurk Effect ExperimentMcGurk Effect Experiment
Is Language Human Specific?Is Language Human Specific?
Do Animals Have Language?Do Animals Have Language?
Talking with Kanzi the Bonobo
Introduction to the Gorilla Foundation: Koko’s Sign Language
Goodbye to Alex the Parrot
Writing AssignmentWriting Assignment
What defines language?Is it unique to humans?
What experiments would you do to identify language correlates in animals?
Reading NeuroscienceReading Neuroscience
Speech SimilaritiesSpeech Similarities
The speech symptoms of people with aphasia tend to be mimicked in their reading symptoms.– Agrammatical speech—Agrammatical
writing– Patients with Broca’s aphasia
comprehend what they read, but have difficulty reading it aloud.
Pure AlexiaPure Alexia
Associated with visual cortex and posterior corpus callosum lesions
Maintain the ability to write, but not read
Perceptual disorder
Dear Dr. Warrington, Thank you for your letter of September 16th. I shall be pleased to be at your office between 10 & 10:30 am on Friday 17th October. I still find it very odd to be able to write this letter but not to be able to read it back a few minutes later. I much appreciate the opportunity to see you.
Yours sincerely,Harry X
Pathways in Pure AlexiaPathways in Pure Alexia Damage only to the left primary visual cortex
– Right visual field is blind; info from the left visual field passes to the right visual cortex
– Information passes to the extrastriate cortex, crosses over the corpus callosum
– Processed in left speech areas, making reading possible but difficult
Damage to the left visual cortex and corpus callosum– Patient cannot read: right visual field is blind, and
information from the left visual field cannot pass over the corpus callosum to the left speech areas
What about damage to the posterior corpus callosum?
HemialexiaHemialexia
Inability to read words that are located only in the left visual field
Words in the right visual field are read normally
DyslexiaDyslexia
Can be developmental or acquired Surface dyslexia
– Deficit in whole-word reading– Associated with damage to left lateral temporal
lobe– Errors are related to visual appearance, not
meaning Phonological dyslexia
– Deficit in sounding out words phonetically– Caused by damage to left frontal lobe
Other DyslexiasOther Dyslexias
Word-Form & Spelling Dyslexia– Inability to recognize or sound out words, but
able to read slowly
Direct Dyslexia– Cannot understand words that they are
reading aloud– For example, may read a word aloud correctly,
but cannot match the appropriate picture for the meaning of the word.
Writing DisordersWriting Disorders
Phonological Dysgraphia– Inability to write words phonetically
based on sounding them outOrthographic dysgraphia
– Ability to write words only when sounding them out
– Difficulty writing words that are not spelled the way they sound
Decoding Phonemes ExperimentDecoding Phonemes Experiment
Concept MappingConcept Mapping
Reading Disorders– Alexia– Dyslexia– Etc
How would you help people with these disorders learn to read?
Improving Your Language SkillsImproving Your Language Skills