This document summarizes a proposed study investigating the neural correlates of noun and verb processing. The study aims to address inconsistencies in previous research by using a lexical decision task combined with a grammatical categorization task on stimuli that systematically vary the verb stem, nominal suffix, and semantics. The study will use fMRI to scan participants and make comparisons between conditions to provide insights into the decompositionality of words and whether different brain regions are involved in syntactic versus semantic processing of nouns and verbs. The results could help determine what aspects of word processing are syntactic versus semantic in nature.
5. Theoretical Background
fMRI Studies
• Main activation located in the Left Inferior Frontal Gyrus
• Processing syntactic information (Friederici et al., 2000)
• (functional vs. content words)
• Processing inflected verbs and nouns (Tyler et al., 2004)
• Decomposition of morphologically complex items (Tyler et
al., 2002)
• Inconsistent results
Wong & Chen, Language and Cognitive Processes, 2012
6. Issues in Previous Studies
DINING + LEAPING vs. WRENS + WEASELS
• QUESTIONS:
• Semantic differences?
• Stem or Suffix?
• Task employed?
7. Design
• Combine two tasks:
• 1) Lexical decision (word / non-word)
• 2) Grammatical classification (noun / verb)
• Compare words which differ in relation to their
• Verbal stem
• Nominal suffix
• Semantics
15. fMRI Data Acquisition
• 3 Tesla Siemens whole body MRI scanner
• 32-channel coil
• Each fMRI session will consist of 208 volumes per run, 33 slices each
• Spatial pre-processing:
• correct for Slice Timing first, then Realign and Unwarp images.
Parameters
• TR: 2000ms
• Interleave slice acquisition with no gap
• TE: 25ms
• Field of view: 192mm
• Voxel size 3x3x3mm
• Matrix: 64x64mm
• T2*-weighted images
17. Neuroanatomical Predictions
Verb Stem Nominal Suffix Semantics
Argument/Excursion Argument/Argue Avalanche/Elephant
BA 44 and 45:
Semantic and
decompositional
difference BA 47:
Syntactic difference
BA 44 and 45:
Semantic difference
Task?
18. Wrap-up
Item Verb Stem Nominal Suffix Semantics
Nominalization Action
(Argument)
Event Noun Action
(Avalanche)
Pseudo-Suffix Action
(Excursion)
Prototypical Noun Object
(Elephant)
Prototypical Verb Action
(Recuperate)
• Similarities in activation may determine what is processed as
‘syntactic’ or ‘semantic’
• Inconsistencies in verb/noun location overcome by more specific
stimuli characteristics
• Identify whether different tasks cause different activation
19. References
Aron, A. R., Robbins, T. W., & Poldrack, R. A. (2004). Inhibition and the right inferior
frontal cortex. Trends in cognitive sciences, 8(4), 170-177.
Cappa, S.F., & Perani, D. (2003). The neural correlates of noun and verb processing.
Journal of Neurolinguistics, 16, 183-189.
Friederici, A. D., Meyer, M., & Von Cramon, D. Y. (2000). Auditory language
comprehension: an event-related fMRI study on the processing of syntactic and lexical
information. Brain and language, 74(2), 289-300.
Tyler, L. K., Randall, B., & Marslen-Wilson, W. D. (2002b). Phonology
and neuropsychology of the English past tense. Neuropsychologia, 40, 1154–1166.
Tyler, L. K., Bright, P., Fletcher, P., & Stamatakis, E. A. (2004). Neural processing of nouns
and verbs: the role of inflectional morphology. Neuropsychologia, 42(4), 512-523.
Wong, A. W. K., & Chen, H. C. (2012). Is syntactic-category processing obligatory in visual
word recognition? Evidence from Chinese. Language and Cognitive
Processes, 27(9), 1334-1360.
What BAs?Also here you could add some brain images from studies (or lesion studies) showing the involvement of this regions for nouns and verbs.Also, someone might wonder: Does this mean that nounrs do not rely at all on PFC regions, and verbs do not depend on lateral temporal cortex? It would be good to mention something about this during your presentation.
For lesion studies, these areas of damage are associated with these classes-overlap in the LIFG, we know this is strongly related to noun and verb processing.-can we pick apart this area for separation?-there are exceptions
-Most consistent activation for nouns and verbs is in LIFG-BUT, there’s been inconsistencies, some show separation, some don’t
Above imaginabilityDifferent semantics are different; tools, animals, fruits differentphonological, orthographic, lexical, semantic or lexical-syntactic level,
What are the baselines?
Lateral temporal – Planned comparisons in each task, based on the studies, what activation do we expect?Refined neuro-hypothesis.44, 45, 47.Pub.med.Visual occipital.
Delete the final collum
300-500ms before word presented, and time after so that the response is within what is captured. TR
Pseudo-randomised sequence ITI (1 – 10 secs)Each word presented for 1000msRespond within 2000ms
This is great, Laura.Despite that the two tasks are consecutive, it would be very important to indicate the subjects what task they are at, which is not possible to infer from the presentation of the (same) wordFor doing so, you can for instance use colors or anything disctintive. You can say that participants will be trained on the task with fillers before going into the scanner, so they will learn the rules beforehand (e.g., blue is lexical task, and green is categorical task). You can also say that you will counterbalance the colors use per each rule/task across subjects.
TR 2 seconds (time repetition)7 conditions960 stimuli presentation.Inter fixation is when there’s nothing on the screen, but they look at it between trials.Total duration 1248 seconds. 21 minutes. Each functional run should be 6.9 minutes (3 runs).208 volumes per functional run.paramtersTR 2TE 20 – 40ms (25 or 30 is standard)field of view: 192mmthickness of slices and voxel size 3x3x3mmmatrix: 64 x 6433 slices to cover whole brain in the 2 secondsInterleave slice acquisition, no gap.T1 because lower TR
Visual – so, visual cortex?If have to press a button, then the motor cortex on the opposing side to the button being pressed (will need to counter-balance this)Semantic activation, syntactic activationVisual word-form area (fusiform gyrus)Brodmann area 17 and 18, 19, visual cortex4 and 6 – motor cortexBrodmann area 44 – semanticsBrodmann area 45 – semantics, generating verbs from nounsBrodmann area 47 - syntax
Whole brain t contrastfor this planned comparison, where will there be more activation and why.Syntax – bilateral temporal cortex – Friederici et al.,
Lateral temporal – Planned comparisons in each task, based on the studies, what activation do we expect?Refined neuro-hypothesis.44, 45, 47.Pub.med.Visual occipital.
