Cognitive Neuroscience of Language Flashcards
1
Q
What are some insights we can get from aphasia?
A
more arguments about domain generality and domain specificity
2
Q
What is speech sound categorization?
A
perceptual narrowing, categorical perception, and the brain
3
Q
What is the behavioral description of Tan?
A
-could only produce one jargon syllable seemed otherwise to be in possession of his senses
-in fact seemed to understand what was being said
4
Q
What was the anatomical description of Tan?
A
-large lesion
-definitely including the third convolution of the frontal lobe (inferior frontal gyrus)
5
Q
What is the geschwind-wernicke model of brain and language?
A
-at the same time as broca’s reports wernicke was observing a different form of language disorder in patients with posterior lesions
-unlike broca’s patients their deficits were more severe for comprehension than for production
-this is a classic double dissociation suggesting that the mechanisms underlying comprehension and production are distinct
6
Q
What region is involved in wernickes aphasia?
A
posterior temporal gyrus
7
Q
How did fmri data formalize structure function relationships in aphasia data?
A
-the symptoms here are defined very broadly
-a-c shows regions that are likely to be damaged in individuals with fluency deficits
-d-f show regions associated with comprehension deficits
-so data from a large number of patients is consistent with a rough double dissociation where posterior regions are associated with perception whereas anterior regions are associated with production
-note that the insula is a real hot spot for fluency deficits even more so than the cortical broca’s area
8
Q
What can we think of producing and comprehending as nicely aligned with?
A
-dorsal and ventral streams
9
Q
What stream is production related to?
A
dorsal stream (action)
10
Q
What stream is comprehension related to?
A
ventral stream (recognition)
11
Q
Where does the dorsal stream start and project forward to?
A
starts in the auditory cortex and projects forward to the motor leanring
12
Q
What does one view contend the key to language is?
A
generativity; the core of langauge is the syntactic structure or grammar - all languages have sets of rules for producing grammatical sentences that all users of the language know implicitly
13
Q
As far as grammar is concerned words or morphemes are what in language?
A
arbitrary and interchangeable
14
Q
Where are the words we know stored?
A
in the lexicon and we learn them explicitly think about the paired associate test for example
15
Q
What distinction is very important in linguistics?
A
-the one between grammar and the lexicon is very important
-geschwinds interpretation of the neuropsychological data seemed to suggest that it was also an important organizing principle for language in the brain
16
Q
What is a lexicon?
A
set of words you know
17
Q
What is grammar?
A
process you use to create sentences
18
Q
What larger argument did the double dissociation observed in broca and werncikes aphasia become part of?
A
a larger argument about the modularity of language
19
Q
What is wernickes aphasia?
A
word salad with neologisms but syntax is roughly intact
20
Q
What is brocas aphasia?
A
telegraphic speech difficulty with word order and grammatical particles (relative sparing of important content words)
21
Q
What aphasia is problems with lexicon?
A
wernickes
22
Q
What aphasia is problems with grammar?
A
brocas
23
Q
Why would brocas actual patients not be classified as brocas aphasics?
A
-they were unable to produce speech at all which means that this is due to motor control issues than premotor issues and they would be classified as suffering from apraxia of speech
24
Q
What was brocas behavioral descirption of tan?
A
-could only produce one jargon syllable
-seemed to be in posession of senses
-seemed to understand what was being said
consider:
-the role of dissociations in this argument why is it crcital that leborgne has other senses intact
-why does a capacity for articulate speech soynd like a more plausible function of a particular regions of the brain than criminality or philopopogenitiveness
-if you could examine tan how would u specify his deficits in terms of linguistics - phoenetic phonological lexical syntactic
25
Why was it interesting to show that Broca's patients have comprehension deficits?
Broca's aphasia always has some level of motor dysfunction
-if agramatic speech merely reflects an attempt to communicate despite motor limitations it may be that their syntatcic abilties are intact but they are limited in tehir ability to prodcue sentences for less intersting reasons
-however if we shoe subtle comprehnsuin deficits we can dissociate grammar from lexicon in the brain - just because a brain injury leads to agramatic speeh does not mean that grammar was injured itself
26
Why do we need psycholinguistic tests to observe grammatical difficulties in comprehension?
-there are alot of redundant cues as to what a speaker intends to say
-alot of language comprehension stakes place in discourse context which clarifies a lot
-maybe brocas patients comprehension depends on these contemporary heruisitics if that were the case you might want to test them with sentences - the dog that the man is biting is mean
27
How did Caramazza and Zurif test grammar deficits in brocas patients? What did they see?
-made sentences like "the dog that the man is biting is mean" and a set of control sentences
RESULTS
-data from sentence picture matching
-healthy controls at all stimulus types
-wernickes are bad at all due to comprehension deficits
-brocas not good with what did what to whom when syntax conflicted with common sense
-data shows that brocas impatcs syntax
28
What is problems that come up with the grammar vs lexicon dichotomy?
why would we assume that the brain is orgnized in this way and that you can point to a region of the brain and say this is involved in grammar and this is involved in the lexicon
29
What is the study conducted by dick et al on broacs and wernickes and healthy controls and tested participants on them determinin which animal in a sentence is doing the action? What were the results?
active - the dog is biting the cat
subject cleft - its the dog that is biting the cat
object cleft - is the cat the dog is biting
pasive - the cat is bitten by the dog
results
-the brocas aphaisa pateints have issues with the syntactically complex stimuli - object cleft is worst and passive is second worst
-wernickes bad at all indicating issues with lexicon
30
When the same study as dick et al was conducted in healthy undergraduates under conditions that stress the language system in different ways (i.e. speeding up speech or asking people to remember lists of numbers as a secondary task), what was seen?
-the object cleft and passive sentences are vulnerable to all manipulations
-this suggests that the comprehensions deficits seen in brocas aphasia may be a performance issue after all
31
Are Broca's aphasics comprehension deficits language specific? What was found in the saying et al study related to this where they asked patients to match the action to the object? What area of the brain was performance correlated to?
-brocas aphasics had difficulty with the task whether the stimuli were linguistic or not
-had issues with this task regardless if the stimuli was linguistic or not - not an issue with syntax specfically more so to both (macth ice cream cone to man)
-performance of the non verbal version of this task was significantly correlated with damage to broca's area (voxel lesion symptom mapping)
32
What is the theory regarding broca's area and cognitive conflict?
-another alternative view is that broca's area LIFG deals with internal conflict domain generally
-detection and and resolves internal or representational conflict
-i.e. sentence from the caramazza and zurif "the dog that the man is iting is black" - even if you parse this sentence perfectly you still have to deal with the conflict between the most likley combination of dog man and bite and the menaing of the sentence
33
What is the anterior cingulate cortex involved in?
conflict monitoring - detects response based conflict
34
What is the evidence that the IFG brocas area is involved in cognitive conflict rather than syntax?
-a sentence comprehension task in which participants are asked to follow simple instructions
-the conditions vary in ambiguity both syntactically and pragmatically
Use the leaf to clean the pig or clean the pig with the lead using the sponge or rock
-in addition to the sentence comprehension task also asked participants to perform a modified stroop paradigm - push the button corresponding to the color of the pixels on the screen ignoring the words (The reaction time cost is due to a number of things one of them is response conflict so it is also there is a button you can push so iif brown is there there is not brown button so you won’t push it even if you want to so nor response conflict )
RESULTS
-a single region of interest was found to be active across participants for both the stroop and sentence comprehension tasks
-further actviiy in this regions was modulated by response conflict in both tasks - brocas area involved in managing response conflict cause when you say something you are choosing between number or words so this is not domain general and works across
35
Are wernicke's aphasics comprehension defiicts language specific?
-wernickes patients were bad at the saygin et al task and asked patients to match environmental sounds to pictures
-no significant difference was observed between verbal and non verbal versions of the task
-So even for words the loss of function is not specific - it is not the words that are damaged it is the ability to map from sounds to meaning
deficits in both verbal and non verbal sound picture matching are associated with wernickes area - the same middle temporal gyrus regions are associated
36
What regions has a number of neuroimaging studies produced results for consistent with a role in nonlinguistic object recognition?
posterior superior middle temporal regions - here activity to visually or auditorily presented objects is compared to scrambled noise controls
-Looking at visual objects and compare those to visual noise stimuli and you get quite a lot of visual cortex a you would expect and this is typical of werncikes areas and this is the loc and present auditory stimuli and when we look at activity in the auditory and visual stimuli and things corresponding to both stimuli see this poster its tenmprola grays area is responding to both teh visual and auditory objects and auditory cortex is going to like auditory and visual will like vs and motor is the same
37
How language specific are deficits in aphasia?
-controversial
-what should be clear is how the terms of the debate have evolved
-new tests - quantitative analyses of behavior and of structure function relationships reveals a great deal
38
What was one of the first congitive functions to e localized by broca and wernickes?
language
39
What has research on the brain basis of langaue often focused on?
questions about the domain specificity of language processes
-this is an issue generally we speek about brocas area supproting syntax and production whereas wernickes area supports lexical word processing and comprehension - there is overlap between production and motor planning conlfict resolution and working memory in bricas area
-there is overlap between linguistic and non linguistic comprehension in wernickes area
-our current techniques cannot dissoication language specific rpocesses from related nonlinguistic processes in the brain
40
What does speech sound categorization involve?
learning to treat many different acoustic events as members of the same category
-this mean learnin not to hear the difference between two sounds in a second language
-the phenomenon of catgeorical perception has consequences for natuve langauge speech perception and for learnin of a second langauge
41
Via a shorter volume onset time what can you do to peach versus beach?
the breath between p and each and b and each in either word is different with b each longer so you can change that and make different words
-your ability too recognize a p or a b depends on your ability to differentiate the sounds from one another - you are transifmring the analog signal into something digital
42
What is are two phenonmenon which occur when learning our native language?
acquired distinctiveness: we become better at perceiving stimulus properties that are critical for distinguishing native language sounds
acquired similarity: we become worse at perceiving properties that are not
43
What study was conducted when examining the development of categorical perception and language specific speech production in infants?
-got a measure of arousal through high volume sucking
-the baby repsonds when the chnage contains a phonetic boundary and were from two different phonemic categorizations
44
In perceptual narrowing for speech categories, at around six months english learning infants show evidence of what?
discriminating speech contrasts they have ever heard before
-over the course of development the ability to perceive these contrasts declines
-this is related to categorical perception because it shows that throwing out of variability that us not relevant to your native language
-6month old infants t=do better than adults
45
What is an example of some contrasts being less salient than others for infants?
-between 6 and 10 months exposure to this contrast in a filipino language enviironment increases it salience
-this means that all speech contrasts are not available innately - exposure to contrasts in the environment is necessary for acquisition in some cases
exposure to contests in the environment is necessary for acquisition in some cases - so they do not show a change for 6-8 month olds but do for 10-12 months
46
What is an example of adults failing to learn second language speech contrasts?
-american english has some unusual contrasts the difference between /r/ and /l/
-japanese has a flap sound a bit like the t in butter that is right in between these two sounds
-japanese speaker learning english late in life rarely master the /r/-/l/ contrast
47
Even after extensive training were adults able to learn second language speech contrasts?
-even after extensive training performance is less than perfect (native listeners would be close to 100% with these stimuli)
-note the dependence in who is talking and the position in the word (i.e. sensitive to irrelvant variance) ( better if same person was sayin the sound iin learning and testing in each trial which is not the same for native speakers )
48
What is a measurement issue which comes up with second language learners in compensating for their difficulties with speech sound categorization?
-in the experiment native japanese speakers were trained on a large number of exemplars of /r/ and /l/ and even when they did vert well in general and they seeemed to learn some stimuli backwards whcih is diffrent from the way native listeners catergorize sounds
-whenever you try to study a process that is unconscious or automatic want to be careful that people are not suing some source of inofrmation you had not intended people zero in on stuff you had not thought of
49
What is one way around problems with meta linguistic tasks: passive paradigms in neutral contexts?
Put an eeg on someones Brian and see what your Brian does when it changes from one sound to the other - were tapping the same processes seen in the study
50
What is a classic passive paradigm known as the mismatch negativity?
its a way of oinexin whether the rain has registered a change from one stimulus to another - standard stimulus is the ra which is very 100-200 ms or so and then get a change which is the la and that is teh deviant stimulus and want to see if we see a difference between teh standard and teh deviant stimulus
-n400 is some pairs of words - if I show you pickle and rope will see something appear cause unexpected
51
When does the mmn mismatch negativity begin?
150-200ms post stimulus
-mismatch repsonse is observed as the diffrenece between a deviant chnage stimulus and a standard repeating stimulus in a stream of sounds
-MMN is very earlyMMN is very early and is negative and is 150 ms post stimulus and its a mismatch repo se cause the obersevd difference between the deviant and standard stimulus
-negatuve is up in eeg
52
When is MMN data often collected?
while participants are not paying particular attention to the stimuli \
53
For simple stimuli the size of the MMN is correlates with what?
the physical difference between the standard and the deviant - for speech sounds this is more complicated
54
for speech sounds why is it more complicated that the size of the MMN does not correlate with the extent of deviance?
speech sounds are indistinguishable in part based in the chnage in the spectral shape of the sounds that reflect the posiiton of different artiuclators in your mouth - the priminences in the spectrum are called formants
55
If you make formant 2 go down and formant 1 go up what happens?
you change what vowel you are hearing - get a lot of infomration about which vowel you are hearing based on the F1 and F2
56
Since there is a huge amount of varaibility in the F1/F2 within categorues and for some cetgoriues there is alot of overlap what does this mean?
this is an example of the lack of invaraince problems and one of the reaosns people think categorical perception is important
57
What was done in the winkler et al study in ho the MMN is shaped by knowledge of speech categories?
compared hungarian and finnish speakers MMNs to sets of vowels that differed by the same amount on F1 and F2
-for finnish speakers it is a different vowels /e/ and /ae/ and for hungarian speakers they are the same vowel /E/
-when the vowel contrast is common to the two language everybody shows the same MMN for the /e/ and /y/ contrast
-when the vowel contrast is present in finnish but not hungarian the finns show a string mmn and the hungarians do not
-this demonstrates that the mmn is shaped by language categories
-that is interesting because the mmn is a very early response that occurs without effortful attention to the stimuli
-interestingly enough the mmn does not seem to track with aquisition of nayive lile perfomrance
-fluent hungarians had native like mmns despite the fact that in an actuve task they performed less well than native speakers at detecting deviants
58
In an fmri of mismatch responses what can you see?
you are able to reconstruct the bold responses to a cluster of stimuli which was lalalalala or rarararara
59
Where can MMN responses be found?
in the supramargial gyrus and posterior superior temporal lobes
60
What are these brain responses to speech contrasts are shaped by?
early experiences
-in japanese syllable end in either a vowel or a nasal like the n in nasal this makes it hard to hear the difference between ebza and ebuza
-but japanese has vowel duration contrasts whcih french and english does not so french speakers have a hard time hearing the difference between ebuza and ebuuza
-jacquemot et al showed that responses in the supramarginal gyrus depended on language background (japanese or french) for the same stimuli
-see corresponding activity in the smg
(acoustic change means they sound different but do not mean different things which is phonological)
61
What happens early on in development in relation to our perceptual abilites for speech?
they seem to narrow so that we are more sensitive to differences in sounds that are contrastive i.e. can make a difference in meaning in our native language
62
What is an early brain response that indexes senstivity to differnces between stimulu and is shpaed by language experience?
MMN
63
What does a similar paradigm in fmri show?
activity in the left smg
-is the left smg the place where speech sounds are discriminated>
64
Does the phoentic perception in these tasks be robust to differnces in talker? (categorical perception is useful so you can recognize the same speech sound as produced by different people as the same thing)
the same areas respond to talker variability as respond to phonetic variability
-in fact we observe diminsihed responses to alternation in phoeneme when talker alternation is included in the stimulus array
65
How are the findings indicative of relative salience of auditory change?
-differences between people with different language backgrounds may be driven by differences in salience of contrast
-this is not surprisin given the role of the tpj in attentional control
-when there is variability in the talker gender the salience of the phonetic change is reduced
66
What is the general model of langauge?
comprehension in posterior and production in frontal areas
67
What is the degree to which the domain specific processes that are specifically tuned to language as their input plays a role?
classical language areas like wrnickes and brocas area play a role in nonlinguistic processing
-brain responses that are sued to measure our sensitivity ti speech are involved in attention
-complexity of language processing makes it hard to isolate purely linguistic functions in the brain
68
