Psycholinguistics Lesson 2 Flashcards
How many hemispheres does the brain have?
2- left hemisphere and right hemisphere
What does cerebral dominance mean?
That one hemisphere is dominant over the other in a particular function.
Analytic, time-based processing is mainly in the ____ hemisphere and Holistic, spatially based processing occurs in the ____ hemisphere.
left
right
What hemisphere is dominant for language processing? (for most right handed people and majority of left handed people)
The Left Hemisphere
who was the Wada test developed by?
John Wada
In the Wada test, a ___ is administered to one of the ____, anaesthetizing it for approx. ____ minutes.
drug
hemispheres
10
After one hemisphere in anaesthetized what are patients asked to do?
Asked to perform language tests
The experiment is then repeated…
on the other hemisphere
If the affected hemisphere is ______-______, verbal behaviour should be affected more severely.
language-dominant
Who found that 96% of right handed people and 70% of left handed people had left hemisphere control of speech?
Rasmussen and Milner, 1977
overall what percentage of people have left hemisphere control of speech?
93%
What did Penfield and Roberts develop in 1950?
Electrical Brain Mapping
What is electrical brain mapping?
When a brief electrical current is administered onto a small area of the patient’s exposed brain while the patient is still awake and they have to perform language tests.
If current is applied to language areas what should happen?
Speech should be disrupted
who found that all patients had language areas located in the left hemisphere but nowhere in the right hemisphere?
Ojemann 1983
What is the corpus callosum?
A bundle of fibres connecting the 2 hemispheres that allows information transfer between the 2 hemispheres
When the corpus callosum is removed there’s no ______ ______ between the 2 hemispheres, what is this sometimes known as?
information transfer
having a split brain
In the 1960’s who tested split-brain patients whose corpus callosum was removed?
Sperry and Gazzaniga
The split brain patients took part in ___ ____ experiments.
visual field
Where does the information on the right visual field go?
To the Left Hemisphere
Where does the information on the left visual field go?
To the Right Hemisphere
What would normally happen in a visual field experiment when people looks at the fixation cross?
Normally people can name or describe words or objects presented in EITHER visual filed.
what could most split brain patients name?
They could name words/objects presented in the RIGHT VISUAL FIELD
What could split brain patients not see?
They couldn’t name/see words/objects presented in the LEFT VISUAL FIELD
What does Sperry and Gazzaniga 1960, show?
It shows that language is localised in the LEFT hemisphere.
what is lateralisation another word for?
cerebral dominance
Lateralisation occurs gradually as a result of _________.
maturation
What possible explanation is there for lateralisation with regard to language processing?
That the LH is better designed for language processing
what does damage to the Left Hemisphere in adults lead to?
Severe language disorders
If there is damage to the left hemisphere in an infant or a child they are far ____ likely to suffer from a language disorder.
less
Even when the entire left hemisphere is removed _________ could recover almost completely.
very young children
What do we mean by plasticity in the brain?
we mean that the brain structure isn’t completely fixed and possesses flexibility
Often ____ isn’t a permanent condition.
aphasia
Damage to the left hemisphere doesn’t always impair ____ abilities, even in adulthood.
language
What can the Right hemisphere take over?
The Right Hemisphere can take over the function of the left hemisphere.
Name 2 language functions that the Right Hemisphere is important for.
Prosody
and
Non-Literal Language processing
What is prosody?
Prosody is the tone of voice, intonation and emphasis we use whilst speaking
What is an impairment in producing and comprehending prosody called?
Aprosodia
How was it discovered that there was a stronger response in the right hemisphere to prosodic cues than the left?
Through Imaging Studies
If you have right hemisphere damage you will have difficulty with _____ meanings and understanding _____. Who discovered this?
metaphor
humour
Brownell
The surface of the left frontal lobe is known as…
Broca’s area
are people with Broca’s aphasia non-fluent or fluent aphasics?
non-fluent aphasics
People with Broca’s Aphasia have ___, _____ and ____ _____ speech.
slow, effortful, poorly articulated
What can’t Broca’s Aphasics compose?
They are unable to compose sentences.
Broca’s aphasic have agrammatism- what does this mean?
this means they have problems with processing grammatical information.
Their ____ suffers as much as their speech (Broca’s). What does this suggest?
writing
this suggests that language rather than vocal control is impaired
What type of sentences can’t people with Broca’s Aplasia comprehend?
They can’t comprehend complex sentences
What did Caplan 2006, Caramazza and Zurif 1976 find?
Broca’s Aphasics can access the meanings of individual words
but have trouble figuring out who did what to whom unless the meanings of the words constrain the roles.
What did Heilman and Scholes 1976 show abput Broca’s Aphasics? (the baby pictures/baby the pictures)
That they have problems processing syntactic information, they have difficulty working out how words in the sentence relate to each other.
What is fluent aphasia also known as?
Wernicke’s aphasia
What do Wernicke’s aphasics have a severe impairment in?
Wernicke’s Aphasics have a severe impairment in comprehending language
Wernicke’s Aphasics can speak- name 4 characteristics of their speech
fast
fluent
well articulated
but meaningless
Broca’s aphasics often have lesions in _____ ____
Broca’s Area
What area is the left-lateralised pre-frontal cortex?
Broca’s area
Wernicke’s aphasics have lesions in the _____ ________. Where is this within the brain?
Wernicke’s Area, it is further back in the brain than Broca’s area- left temporal lobe
What do different brain lesions cause?
Different language functions
Specific areas of the brain are responsible for ______ _______ functions.
specific language
What does WLG stand for?
The Wernicke-Lichteim-Geschwind model
Broca’s and Wernicke’s findings were revisiterd in the 1960’s by _______(_______) who reinvented the _____ originally proposed by Wernicke.
Geschwind 1967
model
How many areas are language functions localised in?
7
What processing does Broca’s Area specialise in?
It converts sounds into articulatory information.
What processing does Primary Motor Cortex specialise in?
Articulation
What is the Arcuate Fasciculus?
A bundle of fibres
What is the function of the Primary Visual Cortex?
To receive visual information
What part of the brain processes visual properties of words?
The Angular Gyrus
What is the function of Wernicke’s area?
Stores the mental lexicon and extracts word meaning and activates sound for production
What part of the brain receives auditory information?
Primary Auditory cortex
______ area stores sound and meaning; activates appropriate representations in comprehension and production.
Wernicke’s
_______ area sequences words, generates grammatical forms and stores motor plans that produce speech output.
Broca’s
A potential problem with WLG theory is that Aphasics are diagnoses…
behaviourally based on symptoms of speech production and comprehension
some Broca’s aphasics have no damage in the ____ _____.
Broca’s area
Some patients with damage to Broca’s area don’t have ____ ______.
Broca’s aphasia
Do all Wernicke’s aphasics have damage in Wernicke’s area?
No
Some patients with damage to ______ area don’t have Wernicke’s _____.
Wernicke’s
aphasia
What differs in terms of lesions between patients?
The size and location of the lesion differs greatly from patient to patient
What is basically the problem with WLG theory?
That everybody’s brain is different and people have different deficits- hard to have a solid correlation
A person who has difficulty in understanding some types of word meaning but not others is said to have a…
Category-specific semantic deficit
In warrrington and Shallice(1984) Patient JBR had difficulty defining and comprehending ____ objects but had no difficulty with ____ objects.
animate (living)
inanimate (non-living)
In warrington and McCarthy 1983, What impairment did patient YOT have?
Patient YOT had the reverse of JBR- impairment in naming inanimate objects instead of animate objects.
what theories are Caramazza & Hills, 1991 and Pinker 1994 involved with?
Localisation theories
What has been useful to argue for localised semantic representations?
category-specific semantic deficits
Define Localisation Theory
the theory that different semantic categories are stored in different physical locations of the brain.
Localisation theory can explain _____ semantic deficits following ___ ____.
category-specific,
brain damage
What happens if we have a lesion in a certain brain area?
We have a deficit in processing specific groups of word meanings.
What were Damasio’s (1996) naming studies trying to find out?
if different area of the brain are involved in semantic processing
In Damasio’s first experiment- who did he test?
Lesion patients
Damasio visually presented the participants with 3 categories of stimuli- name them.
Famous Faces, animals and tools.
What did people with damage in the left temporal pole (TP) problems with?
They couldn’t retrieve the people’s names
What area of the brain was damaged when people had problems naming animals?
Damage in the left infratemporal lobe (IT)
Patients that had damage in the Lateral Temporo-occipitoparcital (IT+) had naming problems for _______.
tools
Damasio’s second experiment involved PET, what does this stand for?
Positron Emission Tomography
what does PET measure?
PET measures blood flow in brain by monitoring the distribution of a radioactive tracer
There will be more blood flow in the brain if there is __________ in that area.
increased neural activity
The lesion and activation studies produced consistent results -what was the conclusion of Damasio’s (1996) experiment?
That there are different areas specifically involved in naming people, tools and animals.
What theory is Damasio’s research consistent with?
Localisation theories
What can localisation theory explain?
Why deficits for living and non-living things cab differ.
What can’t the localisation theory explain?
It can’t explain why deficits in patients are more common for living things than non-living things.
What theory believes that the knowledge about living and non-living things are represented in the same system, but the way activation spreads within the system is different?
Distributed Representation Hypothesis
pulvermuller, 1999
A same brain region could _____ different kinds of ______ information.
activate, semantic
Why are living things harder to discriminate than non-living things?
Because they tend to share Correlated features eg. cat and dog both have 4 legs, tail etc.
non-living things are more likely to have _____,______ features (eg. book + cup)
uncorrelated, distinct
non-living things are ____ to discriminate than living things.
easier
naming living things may require more ____ knowledge than compared to non-living things.
detailed
What does processing more detailed features result in the activation of?
Results in the activation of more anterior (front) regions
What thing do patients with category-specific deficits have more trouble naming?
Living things as they have correlated features making them harder to discriminate.
Patients with category-specific deficits have no problem identifying _____ features of both living/non-living things.
common
Tyler and colleagues (2004) were interested in the level of specificity- what were they interested in finding out?
Whether different parts of the brain get activated depending on how specific people name different objects.
Healthy participants silently named pictures of either living (cat) or non-living (spoon) objects- on 2 levels, name these.
Basic level naming (cat, spoon)
Domain level naming (living, non-living)
Both basic and domain level naming activated the _____ ____ ______ _____.
posterior inferior temporal cortex
basic-level naming additionally activated more ______ regions.
anterior
What region is involved in processing more complex featural information (basic level- cat,spoon)?
Anterior region
What is the posterior region of the brain for?
Responsible for processing simpler features of objects (required by domain level naming eg. non-living/living)
Language functions are ______.
lateralised
What does Left Hemisphere damage result in?
substantial language dysfunction
What does the WLG model offer?
A basic account of language function-brain localisation relationships
