Basque Word Orders, Psycholinguistic and Neurolinguistic Research
Interpreting Neurolinguistic Evidence Careless thinking and critical thinking Ling 411 – 21.
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Transcript of Interpreting Neurolinguistic Evidence Careless thinking and critical thinking Ling 411 – 21.
Interpreting Neurolinguistic Evidence
Careless thinking and critical thinking
Ling 411 – 21
Schedule of Presentations
DelclosPlanum Temp
BanneyerCategories
Ruby TsoWriting
BosleySynesthesia
McClureGram.-Broca
EzzellLg Dev. (Kuhl)
Rasmussen2nd language
BrownLg&Thought
Gilcrease-Garcia
AG
KobyMusic
TsaiTones
RobertsMTG
MauvaisLH-RH anat.
SheltonThalamus
DelgadoAmusia
Joyce LiuRH functions
Tu Apr 13 Th Apr 15 Tu Apr 20 Th Apr 22
Interpreting Linguistic EvidenceCareless thinking and critical
thinking
Wernicke’s area and speech production Broca’s area and speech production Broca’s area and Wernicke’s area in
syntax The meanings of words “Mirror neurons” – very smart? Invoking the computer metaphor
•Retrieval of words, meanings
•Communication between subsystems
Wernicke’s area and speech production
Examples of careless thinking:
Steven Pinker:
Wernicke’s area …was once thought to underlie language comprehension. But that would not explain why the speech of these patients sounds so psychotic.
The Language Instinct (1994)
Friedemann Pulvermüller:
…patients with Wernicke’s aphasia have difficulty speaking…. These deficits are typical…and cannot be easily explained by assuming a selective lesion to a center devoted to language comprehension.
The Neuroscience of Language (2002)
Perceptual structures in motor production
Perceptual structure is used in two ways1. Planning (e.g. visualizing while painting)2. Monitoring
Examples• Phonological recognition in speech production
Cf. Wernicke’s aphasia
• Painting
• Musical production
• Baseball, soccer, tennis, etc.
Interpreting Linguistic EvidenceCareless thinking and critical
thinking
Wernicke’s area and speech production Broca’s area and speech production Broca’s area and Wernicke’s area in
syntax The meanings of words “Mirror neurons” – very smart? Invoking the computer metaphor
•Retrieval of words, meanings
•Communication between subsystems
Broca’s area and speech production - I
Careless thinking previously considered:John Pinel (Biopsychology textbook):
Surgical excision of Broca’s area failed to result in loss of speech production (after recovery from surgery)
Broca’s Area: Not for Speech Production?
Surgical excision was done in two stages. Following completion of the second stage, no speech-related problems were reported.
John Pinel, Biopsychology (1990:560),Adapted from Penfield & Roberts, 1959
Patient D.H.
Broca’s Area: Not for Speech Production?
What Pinel neglects to mention, but it is in Penfield & Roberts: Patient D.H. was a young boy who had been having seizures, originating in this part of his brain. John Pinel, Biopsychology (1990:560),
Adapted from Penfield & Roberts, 1959
Patient D.H.
More on patient D.H.
Eighteen years old at time of surgery Had suffered from seizures causing an
inability to speak from the age of 3 1/2
Apparently, “the congenital abnormality had caused displacement of function”
Penfield & RobertsSpeech and Brain Mechanisms(1959: 163)
Broca’s area and speech production - II
Influential paper by Alexander et al. (1990)
Motivation for the study•Maybe it’s not just Broca’s area damage that
is responsible for some of the symptoms of “Broca’s aphasia”
•Maybe some of them result instead from damage to neighboring areas
They studied a group of patients Distinguished 3 subtypes of Broca’s
aphasia
Three subtypes in Alexander study
1. Impaired speech initiation• Symptom traditionally attributed to
transcortical motor aphasia
• Area of damage: frontal operculum
2. Disturbed articulatory function• Area of damage: lower primary motor cortex
3. The classical Broca’s aphasia syndrome• More extensive damage
Type I
One patient Area of damage
•Frontal operculum•Adjacent middle frontal gyrus•Subjacent subcortical white matter
Speech quality normal Normal repetition Speech terse and delayed in initiation Speech grammatically correct! Anomia and semantic paraphasias
Insula and operculaView with opercula pulled back to expose insula
1.Short gyri of insula 2.Long gyrus of insula 3.Superior temporal gyrus 4.Circular sulcus of insula 5.Frontal operculum 6.Frontoparietal operculum 7.Temporal operculum
Original Brodmann Map - Colorized
Outlines - with Functional Attribution
Type I – critical appraisal Area of damage
•Frontal operculum •Adjacent middle frontal gyrus•Subjacent subcortical white matter
Symptoms•Speech quality normal•Normal repetition•Speech terse and delayed in initiation•Speech grammatically correct!•Anomia and semantic paraphasias
The symptoms are those of transcortical motor aphasia
Type I (cont’d)(from Alexander study)
Other relevant studies•Patients with frontal operculum lesion but
with primary motor cortex spared•Symptoms like those usually called TCMA•Speech output
“Terse, laconic” Grammatical, sentence-length Semantic paraphasias Normal articulation
•Evidently, damage to subjacent white matter “is essential for lasting aphasia after lesions in the frontal operculum” (Alexander et al. 1990” 357)
Type I (cont’d)(from Alexander study)
Other relevant studies•Patients with frontal operculum lesion but
with primary motor cortex spared•Symptoms like those usually called TCMA•Speech output
“Terse, laconic” Grammatical, sentence-length Semantic paraphasias Normal articulation
•Evidently, damage to subjacent white matter “is essential for lasting aphasia after lesions in the frontal operculum” (Alexander et al. 1990” 357)
Type I (cont’d)(from Alexander study)
Other relevant studies•Patients with frontal operculum lesion but
with primary motor cortex spared•Symptoms like those usually called TCMA•Speech output
“Terse, laconic” Grammatical, sentence-length Semantic paraphasias Normal articulation
•Evidently, damage to subjacent white matter “is essential for lasting aphasia after lesions in the frontal operculum” (Alexander et al. 1990” 357)
Type II
Patients 2-6 in Alexander et al. (1990) study Areas of damage
• Frontal operculum
• Lower primary motor cortex
• Anterior insula
• White matter deep to these regions
Right facial paresis and mild right hand weakness Defective articulation Sentence-length grammatically normal utterances!
• Except for initiation struggle
• Except for patient #6: single word utterances
Type II (cont’d)
Other studies support the attribution of dysarthria to primary motor cortex•Patients with
Small shallow lesions in lower motor cortex
Frontal operculum not involved
•Labels that have been used Aphemia Cortical dysarthria Apraxia
(Alexander et al. 1990: 357)
Type III
Patients 7-9 in Alexander et al. (1990) study Areas of damage:
•Lower motor cortex and/or subjacent white matter•Anterior superior insula•Lateral putamen (a nearby subcortical structure)•Frontal operculum spared
Right central facial paresis Aphasia symptoms similar to Type II
• Including absence of agrammatism Phonemic paraphasias in repetition One patient (#9) had virtually no speech
output
Receptive agrammatism
“All cases had some impairments in auditory comprehension at the level of complex sentences or multistep commands.” (Alexander et al. 1990: 360)
Indicates short-term memory deficit
Confounding factors
“We did not evaluate any of the patients in the acute phase of their illnesses; all were referred to the Boston VAMC for speech and language therapy.” (Alexander et al. 1990: 353)
Localization of lesions was done by CT scan – not sensitive enough to detect small areas of damage (360)
The importance of plasticity
“In the acute phase, these patients may have traditional, nonfluent aphasia – articulation impairment, prosodic impairment, and agrammatical, shortened utterances. The evolved disorder is, however, much less severe than that; grammatical, sentence-length utterances return, albeit still labored and paraphasic and with speech impairment.” (Alexander et al. 1990:361)
Recovery is not so good if extensive white matter involvement
Another study
Taubner, Raymer, and Hellman 1999, “Frontal-opercular Aphasia”: 5 types:1. “Verbal akinesis” like Trans-cortical motor
aphasia – supplementary motor area and cingulate gyrus
2.Disorders of grammar – pars opercularis3.Phonemic disintegration – primary motor
cortex4.Defects of lexical access – pars triangularis
and adjacent frontal cortex5.Mixed defects
Proceed with Caution!
How should we interpret the results of the Alexander study?
Some researchers have concluded that damage to Broca’s area is not responsible for Broca’s aphasia after all•Reason: No lasting impairment of speech
production if only Broca’s area is damaged, without white matter involvement
Alternative explanation?
Alternative explanation
Plasticity N.B. Patients were examined only after
they had had time to recover, not in the acute phase
The evidence indicates that•Functions of Broca’s area can be partly
regained by recruitment of neighboring area(s)
•But: such recovery is impaired if there is also damage to subjacent white matter
Interpreting Linguistic EvidenceCareless thinking and critical
thinking
Wernicke’s area and speech production Broca’s area and speech production Broca’s area and Wernicke’s area in
syntax The meanings of words “Mirror neurons” – very smart? Invoking the computer metaphor
•Retrieval of words, meanings
•Communication between subsystems
Friederici Fig. 1Syntactic networks in the human brain. (a) Depicts the two neural networks for syntactic processing and their fronto-temporal involvement (function) schematically.
(b) Shows fiber tracting as revealed by DTI (structure) in an individual subject: top right, with the starting point (green dot) being BA 44 and bottom right, with the starting point (blue dot) being the frontal operculum.
Friederici Figure 2
Fiber tracts between Broca's and Wernicke's area. Tractography reconstruction of the arcuate fasciculus using the two-region of interest approach. Broca's and Wernicke's territories are connected through direct and indirect pathways. The direct pathway (long segment shown in red) runs medially and corresponds to classical descriptions of the arcuate fasciculus. The indirect pathway runs laterally and is composed of an anterior segment (green), connecting Broca's territory and the inferior parietal cortex (Geschwind's territory), and a posterior segment (yellow), connecting Geschwind's and Wernicke's territories.
Wernicke’s & Broca’s areas for syntax?
Combining functional MRI and DTI, two of these pathways were defined as being relevant for syntactic processes [44]. Functionally, two levels of syntactic processing were distinguished, one dealing with building a local phrase (i.e. a noun phrase consisting of a determiner and a noun ‘the boy’) and one dealing with building complex, hierarchically structured sequences (like embedded sentences ‘This is the girl who kissed the president’). DTI data [44] revealed that the frontal operculum supporting local phrase structure building [14] and [44] was connected via the UF to the anterior STG which has been shown to be involved in phrase structure building as well [14]. The dorsal pathway connects BA 44 which supports hierarchical structure processing [42] and [45], via the SLF to the posterior portion of the STG/STS, which is known to subserve the processing of syntactically complex sentences 51 I. Bornkessel et al., Who did what to whom? The neural basis of argument hierarchies during language comprehension, Neuroimage 26 (2005), pp. 221–233. Article | PDF (300 K) | View Record in Scopus | Cited By in Scopus (53)[51]. This latter network was, therefore, taken to have a crucial role in the processing of syntactically complex, hierarchically structured sentences. (Friederici 2009, p. 179)
Critique of Friederici paper by Weiller et al. (August 2009)
Friederici claims the dorsal pathway ‘to be crucial for the evolution of human language, which is characterized by the ability to process syntactically complex sentences’. …
As suggested in our paper, ‘the involvement of the dorsal stream for processing of complex syntactic operations might be partially explained as a result of an increase in syntactic working memory load’ [2]. Syntax and memory are hard to keep apart.
Trends in Cognitive Sciences vol. 13, Issue 8,
September 2009. pp. 369-370.
Hickok on phonological working memory
“… Broca’s area and the SMG are involved in speech perception only indirectly through their role in phono- logical working memory which may be recruited during the performance of certain speech perception tasks.”
Hickok 2000: 97
“The sound-based system interfaces not only with the conceptual knowledge system, but also with frontal motor systems via an auditory-motor interface system in the inferior parietal lobe. This circuit is the primary substrate for phonological working memory, but also probably plays a role in volitional speech production.
Hickok 2000: 99
Interpreting Linguistic EvidenceCareless thinking and critical
thinking
Wernicke’s area and speech production Broca’s area and speech production Broca’s area and Wernicke’s area in
syntax The meanings of words “Mirror neurons” – very smart? Invoking the computer metaphor
•Retrieval of words, meanings
•Communication between subsystems
Impairment of nominal concepts
Access to nominal concepts is impaired in extra-sylvian sensory aphasia
Type I – Damage to temporal-parietal-occipital junction area• I.e., lower angular gyrus and upper area 37• Poor comprehension• Naming strongly impaired• Semantic paraphasia
Type II –Damage to upper angular gyrus • Variable ability to comprehend speech• Naming strongly impaired• Few semantic paraphasias• Many circumlocutions
2 Cases of Rapp & Caramazza (1995)
E.S.T. (901b) – Left temporal damage
•“Meaning spared, couldn’t say the word”: R&C
J.G. (902a) – Left posterior temporal-parietal
•Meaning spared, couldn’t spell the word correctly, but phonological recognition okay
Cf. Rapp & Caramazza, Disorders of lexical processingand the lexicon (1995)
Patient E.S.T. (Rapp&Caramazza 1995:901b)
Left temporal damage Shown picture of a snowman
•Unable to name it•“It’s cold, it’s a ma… cold … frozen.”
Shown picture of a stool•“stop, step … seat, small seat, round seat,
sit on the…” Shown written form ‘steak’
•“I’m going to eat something … it’s beef … you can have a [së] … different … costs more …”
What can we conclude?
Assessment of E.S.T. by Rapp & Caramazza
Responses of E.S.T. indicate awareness of the meanings (SNOWMAN, STOOL, STEAK)
Therefore, “meaning is spared” (according to Rapp & Caramazza)
Warning: Proceed with caution
The assumption of Rapp&Caramazza is easy to make• I.e., that meaning (conceptual information) is
spared
But there’s more to this than meets the eye!
As we have seen, conceptual information is widely distributed
We only have evidence that some of the conceptual information is spared
Patient E.S.T. – a closer look
Left temporal damage Picture of a snowman
•“It’s cold, it’s a ma… cold … frozen.” Picture of a stool
•“stop, step … seat, small seat, round seat, sit on the…”
Written form ‘steak’•“I’m going to eat something … it’s beef …
you can have a [së] … different … costs more …”
These are not definitions This is connotative information
•Vague semantic notions about the meanings
Compare patient J.G. (902a)
Damage: Left posterior temporal-parietal
Meaning spared, couldn’t spell the word correctly, but phonological recognition okay•digit:
D-I-D-G-E-T “A number”
•thief: T-H-E-F-E “A person who takes things”
These are actual definitions
The Role of RH in semantics
Conceptual information, even for a single item, is widely distributed•A network
•Occupies both hemispheres
RH information is more connotative•LH information more exact
Connotative information in RH
Tests on patients with isolated RH resulting from callosotomy
RH has information about (many) nouns and verbs• Not as many as in LH
Semantic information differently organized in RH Zaidel (1990): “… the right hemisphere is
characteristically connotative rather than denotative … . The arcs [of the semantic network] connect more distant concepts … and the organizing semantic relationships are more loosely associative and dependent on experience” (125)
Baynes & Eliason, The visual lexicon: its access and organization is commissurotomy patients (1998)
Semantic information: E.S.T. and J.G.
Patient J.G. – real definitions•digit: “A number”
• thief: “A person who takes things”
Patient E.S.T. – connotative information•snowman: “It’s cold, it’s a ma… cold … frozen.”
•stool: “ … seat, small seat, round seat, sit on the…”
•steak: “I’m going to eat something … it’s beef … you can have a [së] … different … costs more …”
Conclusion about E.S.T.
RH semantic information is intact LH semantic information is wiped out Phonological information is spared in
both hemispheres Question: Why can’t the RH semantic
information be conveyed to LH phonology?
Corpus Callosum
(revealed by excision of top of right
hemisphere)
Corpus Callosum
Interpreting Linguistic EvidenceCareless thinking and critical
thinking
Wernicke’s area and speech production Broca’s area and speech production Broca’s area and Wernicke’s area in
syntax The meanings of words “Mirror neurons” – very smart? Invoking the computer metaphor
•Retrieval of words, meanings
•Communication between subsystems
Mirror Neurons
“What makes them so smart?” (already considered)
• It’s a matter of hierarchical organization
Implications of hierarchical organization
Nodes at a high level in a hierarchy may give the appearance of being very “smart”
This appearance is a consequence of their position — at top of hierarchy
As the top node in a hierarchy, a node has the processing power of the whole hierarchy•Grandmother nodes•Mirror neurons•Compare:
The general of an army The head of a business organization
Interpreting Linguistic EvidenceCareless thinking and critical
thinking
Wernicke’s area and speech production Broca’s area and speech production Broca’s area and Wernicke’s area in
syntax The meanings of words “Mirror neurons” – very smart? Invoking the computer metaphor
•Representation of information
•Retrieval of words, meanings
•Communication between subsystems
The brain and the computer
Conference abstract, March 28, 2009:
Mark Jude Tramo, MD PhD, Harvard, MIT, & Mass Gen Functional Brain Organization in Relation to Emotion and Meaning in Music
When we experience the beauty of music…there is no sound in our brains…. All acoustic information striking our eardrums is transformed into neural information represented by patterns of electrical activity – strings if 0’s and 1’s whose bits vary depending on the pitch, loudness, duration, consonance, and timbre of each note, harmonic interval, and chord….
Retrieval from memory
“inability to retrieve the word”•As if the word were stored in some kind of
symbolic form in some memory location, from which it has to be retrieved
Better: inability to access the internal representation of the word
Links for intermodal communication
Examples: •Phonological – grammatical – semantic•Phonological recognition – phonological
production I.e., Wernicke’s area and Broca’s area
Two related problems: •What information is transmitted?•Over what kind of connection?
Transmitting information
For example, • from angular gyrus to Wernicke’s area
Conceptual or lemma inf in AG Phonological inf in Wernicke’s a.
• from Wernicke’s area to Broca’s area Some kind of phonological information
•Some kind of code?
•Phonemic transcription?
•Phonological image in Wernicke’s a.
•Phonological motor program in Broca’s a.
What kind of connection?
Two possibilities•The way its done in computers
Vector coding, a bus Only a few fibers needed But: some means of coding is needed
•Local coding, individual connections A very large number of fibers needed By comparison, grossly inefficient
Vector coding vs. Local coding
Vector coding requires only a small bus•A 32-bit bus can carry and of 232 items of
information
•The way it’s done in personal computers Nowadays, many use a 64-bit bus
Local coding requires a very large bus•A separate fiber for each item
•For arcuate fasciculus, hundreds of thousands
Anatomical evidence can provide answer•How many fibers in arcuate fasciculus?
Anatomical evidence:Wernicke’s area and Broca’s area
Connected by arcuate fasciculus Auditory phonological images linked
to articulatory images Individual connections would require
many thousands of fibers How many fibers in arcuate
fasciculus?
How many Fibers in Arcuate fasciculus?
Selden (1985:300): “macroscopically most obvious”
Consists of axons of neurons distributed throughout Wernicke’s area
Therefore, millions of fibers Different fibers originate in different
locations throughout Wernicke’s area
How many fibers in arcuate fasciculus:theoretical calculation
From each minicolumn, at least one axon to Broca’s area
How many minicolumns in Wernicke’s area?•20 sq cm x 145,000 minicolumns per sq cm
• 2,900,000
Therefore, at least 2,900,000 axons in arcuate fasciculus
So what is the information that is sent?
We have to avoid thinking of the brain as a computer
An axon sends only one kind of information:•Activation
Can come in different degrees• i.e., different frequencies of firing
•Nothing else needed, since it is a unique connection
This is a property of connectivity •All the information is in the connectivity
•“Connectivity rules!”
end