advances course of psycho …basics of mri functional mri: bold pros and cons 4 fmri and language...

BrainKaan & Swaab 2002

Neuroimaging Methods: (f)MRIfMRI and Language

Kepa Erdozia, Itziar Laka

ADVANCES COURSE OFPSYCHO-/NEUROLINGUSITICS

fMRI research in Language

Master in Linguistics 2009-2010

17/02/2010

Master in Linguistics 2009-2010 ADVANCES COURSE OF PSYCHO-/NEUROLINGUSITICS



Contents

1 Brain

2 Kaan & Swaab 2002Syntactic ComplexityCogntive ProcessesTransformational vs. Working Memory Models

3 Neuroimaging Methods: (f)MRIBasics of MRIfunctional MRI: BOLDPros and Cons

4 fMRI and LanguageKaan and Swaab 2002Friederici 2004




Brain: White and Grey matter




Brain: Lobes and Areas




Brain: Brodmann’s areas




IFG, STS, ...




Syntactic ComplexityCogntive ProcessesTransformational vs. Working Memory Models

Kaan & Swaab 2002

Syntactic ComplexityCogntive ProcessesTransformational Model vs. Working Memory Model





Syntactic Complexity

Identifying who did what to whom enables humans tounderstand sentences.Syntactic information helps us to combine the words wehear or read in a particular way such that we can extractthe meaning sentences.A sentence is more complex if the order of the nounphrases that receive the thematic role (or simply put, wordorder) is non-canonical, that is deviates from theagent-before-patient order.





Cogntive Processes

Is language (syntax) a general cognitive processes suchas memory and atention?Is language (syntax) a cognitive module separable fromother more general cognitive processes?Has syntax separable properties from semantic-conceptualinformation (meaning).





Transformational vs. Working Memory Models

Transformational ModelArguments displaced over their base-generated positionbecause of interpretative restrictions.More displacements→ More complexityFurther elements move→ Bigger the complexity

Working Memory ModelThe linear order of the elements.The syntactic distance vs. the linear distance






A dissociation of these compething accounts is oftenimpossible because in most cases the language-internal

complexity of permuted sentence structures is accompaniedinvariably by increasing costs of a more general cognitive

nature (e.g. working memory, task difficulty, and acceptability)(Grewe et al., 2005).

“A common assumption is that the sentence processorreconstructs the original agent-before-patient order in clauseswith non-canonical order by postulating an empty element in

the original position of the patient. Hence, patient-before-agentsentences involve an additional syntactic operation. In adition,

patient-before-agent sentences impose a larger burden onworking memory, because the first noun phrase (correspondingto the eventual patient) cannot be syntactically and thematically

integrated until that point.” Kaan & Swaab 2002, Box 1.






A dissociation of these compething accounts is oftenimpossible because in most cases the language-internal

complexity of permuted sentence structures is accompaniedinvariably by increasing costs of a more general cognitive

nature (e.g. working memory, task difficulty, and acceptability)(Grewe et al., 2005).

“A common assumption is that the sentence processorreconstructs the original agent-before-patient order in clauseswith non-canonical order by postulating an empty element in

the original position of the patient. Hence, patient-before-agentsentences involve an additional syntactic operation. In adition,

patient-before-agent sentences impose a larger burden onworking memory, because the first noun phrase (correspondingto the eventual patient) cannot be syntactically and thematically

integrated until that point.” Kaan & Swaab 2002, Box 1.Master in Linguistics 2009-2010 ADVANCES COURSE OF PSYCHO-/NEUROLINGUSITICS




extended Argument Dependency Model

Minimality (Bornkessel and Schlesewsky 2006)In the absence of explicit information to the contrary, thehuman language comprehension system assigns minimalstructures. This entails that only required dependenciesand relations are created.

Prominence Hierarchy+nominative > -nominative+pronoun > -pronoun+animate > -animate+specific/+definite > -specific/-definite+actor > -actor




Basics of MRIfunctional MRI: BOLDPros and Cons

(functional) Magnetic Resonance Imaging





MRI Physics

A proton has a positive electric charge, and because itspins around itself, it produces a small magnetic field.Miniature bar magnet with a north and south pole





MRI Physics

Spins align with magnetic field B0

Outside scanner Inside scanner





MRI image: T1

T1: Spins go back to up/downstates.

T1 is unique to every tissue:Time constant T1 is defined asthe point where 63 % of themagnetization M has recoveredalignment with B0

T1 relaxation called longitudinalrelaxation.Returning to equilibrium





MRI image: T1

T1: Spins go back to up/downstates.T1 is unique to every tissue:Time constant T1 is defined asthe point where 63 % of themagnetization M has recoveredalignment with B0






MRI image: T1


T1 relaxation called longitudinalrelaxation.

Returning to equilibrium





MRI image: T1







fMRI: BOLD Response





Supplying Energy

Capillary networks supply glucose and oxigen.Haemoglobin carries glucose and oxigen to the neurons.





What does BOLD measure?

Changes in Magnetic properties of Haemoglobin

More oxyhaemoglobin→ increase signal

More deoxyhaemoglobin→ decrease signal

So... we are NOT measuring oxigen usage directly





Haemodynamic Response Function

1 Initial Dip.2 Oversupply of oxygenated blod.3 Decrease before return to baseline.





fMRI: Pros and Cons

ProsGreat spatial resolution

Cuantitative changes in specific brain areasGlobal Techniques (neural networks)

Cons

Poor temporal resolutionNoisy ScannerLimited space inside the magnet





fMRI: Pros and Cons

ProsGreat spatial resolutionCuantitative changes in specific brain areas

Global Techniques (neural networks)

Cons






fMRI: Pros and Cons

ProsGreat spatial resolutionCuantitative changes in specific brain areasGlobal Techniques (neural networks)

Cons






fMRI: Pros and Cons


ConsPoor temporal resolution

Noisy ScannerLimited space inside the magnet





fMRI: Pros and Cons


ConsPoor temporal resolutionNoisy Scanner

Limited space inside the magnet





fMRI: Pros and Cons


ConsPoor temporal resolutionNoisy ScannerLimited space inside the magnet




Kaan and Swaab 2002Friederici 2004

Kaan and Swaab 2002

Is Broca the seat of Syntax?Evidence from Aphasia

Left Anterior Temporal Lobe is also important in syntacticprocessing

Broca’s aphasics do not completely lack knowledge of syntax.

Broca’s aphasics exhibit semantic deficits

Broca’s aphasics not deficit of knowledge but a processing deficit

The brain areas that are damaged in Broca’saphasics need not to be the areas where

syntactic knowledge is stored.





Isolating Syntax

In previous Literature1 Complex vs Simple sentences

2 Sentences vs. Lists of Words3 Senteces vs. Jabberwocky4 Correct vs. Incorrect sentences





Isolating Syntax

In previous Literature1 Complex vs Simple sentences2 Sentences vs. Lists of Words

3 Senteces vs. Jabberwocky4 Correct vs. Incorrect sentences





Isolating Syntax

In previous Literature1 Complex vs Simple sentences2 Sentences vs. Lists of Words3 Senteces vs. Jabberwocky

4 Correct vs. Incorrect sentences





Isolating Syntax

In previous Literature1 Complex vs Simple sentences2 Sentences vs. Lists of Words3 Senteces vs. Jabberwocky4 Correct vs. Incorrect sentences





Complex vs. Simple Sentences

BROCA (BA 44, 45)Complex conditions involveadditional syntacticoperations

Canonical Word OrderReconstructions vs. WorkingMemory Load





Complex vs. Simple Sentences

BROCA (BA 44, 45)Complex conditions involveadditional syntacticoperationsCanonical Word OrderReconstructions vs. WorkingMemory Load





Sentences vs. Words

no Broca activation

Very simple sentences were used.

→ Broca is not necessarily involvedin syntactic operations

but only comes into play when theprocessing load increases.

Temporal Lobe

sometimes bilateral

patients with morphosyntacticproblems

superior and middle temporal gyri(BA 22, 21)





Jabberwocky and Syntactic Prose

examplesThe mumphy folofel fonged the apole trecon.The infuriated water grabbed the justifieddream.

STSPosterior superior Temporal SulcusAnterior Superior Temporal Sulcus





Correct vs. Incorrect Sentences

Syntactic violations haveconsequences for the semanticinterpretation.Detecting syntactic errors ofJabberwocky enlarge activity inleft BA45





Kaan and Swaab 2002

Conclusions 11 Is there a specific area for syntax?

NO

2 Temporal Lobeanterior, middle and posteriro parts of the superior andmiddle temporal gyri.

3 Are areas unique for syntactic processing?NOBroca and Temporal areas has been activated inprocessing of syntactically unconnected words, lists ofsyllables, semantics, even during music perception





Kaan and Swaab 2002

Conclusions 11 Is there a specific area for syntax?

NO2 Temporal Lobe

anterior, middle and posteriro parts of the superior andmiddle temporal gyri.

3 Are areas unique for syntactic processing?NOBroca and Temporal areas has been activated inprocessing of syntactically unconnected words, lists ofsyllables, semantics, even during music perception





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.

None of these areas are unique for syntax.Brain modularity for language remains unclear.Middle and superior temporal lobes→ lexical processing.Anterior temporal lobe→ encoding information.Borca→ storing non-integrated material.Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.None of these areas are unique for syntax.

Brain modularity for language remains unclear.Middle and superior temporal lobes→ lexical processing.Anterior temporal lobe→ encoding information.Borca→ storing non-integrated material.Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.None of these areas are unique for syntax.Brain modularity for language remains unclear.

Middle and superior temporal lobes→ lexical processing.Anterior temporal lobe→ encoding information.Borca→ storing non-integrated material.Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.None of these areas are unique for syntax.Brain modularity for language remains unclear.Middle and superior temporal lobes→ lexical processing.

Anterior temporal lobe→ encoding information.Borca→ storing non-integrated material.Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.None of these areas are unique for syntax.Brain modularity for language remains unclear.Middle and superior temporal lobes→ lexical processing.Anterior temporal lobe→ encoding information.

Borca→ storing non-integrated material.Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.None of these areas are unique for syntax.Brain modularity for language remains unclear.Middle and superior temporal lobes→ lexical processing.Anterior temporal lobe→ encoding information.Borca→ storing non-integrated material.

Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Kaan and Swaab 2002

Conclusions 2Syntactic processing involves multiple brain areas.None of these areas are unique for syntax.Brain modularity for language remains unclear.Middle and superior temporal lobes→ lexical processing.Anterior temporal lobe→ encoding information.Borca→ storing non-integrated material.Right areas→ Prosody, ambiguity, discourse processing,and error detection.





Friederici 2004

Processing local transitionsversus long-distance syntactic

hierarchiesTRENDS in Cognitive Sciences

Vol.8 No.6 2004





PSG vs. FSG

Non-humans primates

Fitch and Hauser 2004





Non-humans, PSG vs. FSG





FOP: activacion para las dosgramaticas. No interaccionsignificativa entre GrammarType y Violation

BROCA: activacion solo paraPSG. La dificultad de la tareano esta correlacionada con laactividad de Broca.

Friederici et al. 2006





FIN


advances course of psycho …basics of mri functional mri: bold pros and cons 4 fmri and language...

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