neuroanatomy of language 2 sept 13, 2013 – day 10

NEUROANATOMY OF LANGUAGE 2SEPT 13, 2013 – DAY 10

Brain & LanguageLING 4110-4890-5110-7960NSCI 4110-4891-6110Harry HowardTulane University

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Course organization• The syllabus, these slides and my recordings are

available at http://www.tulane.edu/~howard/LING4110/.• If you want to learn more about EEG and neurolinguistics,

you are welcome to participate in my lab. This is also a good way to get started on an honor's thesis.

• The grades are posted to Blackboard.

9/18/13 Brain & Language - Harry Howard - Tulane University

http://www.tulane.edu/~howard/LING4110/

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REVIEW


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Linguistic model, Fig. 2.1 p. 37


Discourse model

SyntaxSentence prosody

MorphologyWord prosody

Segmental phonologyperception

Acoustic phonetics Feature extraction

Segmental phonologyproduction

Articulatory phonetics Speech motor control

INPUT

SEMANTICS

Sentence level

Word level

9/18/13 Brain & Language - Harry Howard - Tulane University 5

Short history of researchDate Event1836 Abercrombie?

1836 Marc Dax claimed that the LH of right-handers has “memory for words”

1861 Paul Broca claimed that the LH of right-handers has “faculty of articulate speech”

1874Karl Wernicke discovered that damage to a certain area could cause receptive aphasia.John Hughlings Jackson claimed that the LH is responsible for language, while the RH is responsible for visual cognition (recognition, discrimination, recall).

WWI-II Many observations of the cognitive results of head injuries

end WWII Juhn A. Wada developed carotid amytal test for cerebral dominance for speech

1950s Penfield & Wilder use cortical stimulation to map the cortex > treat epilepsy, discover the motor-sensory homunculus

1960s Corpus callosotomy (commissurotomy) > split-brain patients

1970s Hemifield tachistoscopy, dichotic listening > laterality research

1980s Noninvasive imaging techniques

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MACROSTRUCTUREThe parts of the brain that you can see with the naked eye



Questions• What are the axes of the brain? • What are the lobes of the brain and what do they do? • What connections important for language? • How does one refer to the areas of the brain?

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AXES



Vertical axis: ventral/dorsal• Orientation of picture

• Which way is forward?• to the left: cerebellum at back

• Which hemisphere do we see?• medial side of right; left is cut away

> sagittal view• Vertical axis

• Dorsal is up, like dorsal fin (dorsal comes from Latin word for back)

• Ventral is down (ventral comes from Latin word for belly)

• Cortical vs. subcortical division• Cerebrum vs. cerebellum• Cerebral cortex (neocortex) vs.

cerebellar cortex

Longitudinal axis: anterior/posterior

• lobes• Sylvian fissure• perisylvian area



Longitudinal axis, functions


Motor & somatosensory homunucli (sg. homunculus)


Lateral axis: left/right


Lateral axis• General

• Which way is anterior?• motor and sensory organs are

crossed (decussation)• ipsilateral, contralateral

• LH• language• math• logic

• RH• spatial abilities• visual imagery• face recognition• music

CONNECTIONS


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The cerebrum is mostly connections


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Diffusion tensor imaging


Connections

Corpus callosum Arcuate fasciculus


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NAMING CONVENTIONSHow to refer to specific areas of the brain


Gyrii• AnG - angular gyrus• FP - frontal pole• IFG - inferior frontal gyrus• IOG - inferior occipital gyrus• ITG - inferior temporal gyrus• LOG - lateral occipital gyrus• MFG - middle frontal gyrus• MTG - middle temporal gyrus• OG - orbital gyrus• oper - pars opercularis (IFG)• orb - pars orbitalis (IFG)• tri - pars triangularis (IFG)• poCG - postcentral gyrus• preCG - precentral gyrus• SFG - superior frontal gyrus• SOG - superior occipital gyrus• SPL - superior parietal lobe• STG - superior temporal gyrus• SmG - supramarginal gyrus• TP - temporal pole


Sulcii• cs - central sulcus (Rolandic)• hr - horizontal ramus• ifs - inferior frontal sulcus• ios - inferior occipital sulcus• ips - intraparietal sulcus• syl - lateral fissure (Sylvian)• los - lateral occipital sulcus• ls - lunate sulcus• pof - parieto-occipital fissure• pocs - postcentral sulcus• precs - precentral sulcus• sfs - superior frontal sulcus• tos - transoccipital sulcus• vr - vertical ramus


Brodmann's areas


Brodmann's areas, functions


Stereotaxic (Talairach) coordinates• MRI scans vary greatly between

individuals due to differences in slice orientation and brain features (i.e. brain size and shape varies across individuals).

• Therefore, it is generally useful to ‘normalize’ scans to a standard template.

• Normalization is the process of translating, rotating, scaling, and maybe warping a brain to roughly match a standard template image.

• After normalization, it is possible to report locations using stereotaxic (“Talairach”) coordinates, which are three numbers (X,Y,Z) that describe the distance from the anterior commissure (the 'origin' of Talairach space).

• The X,Y,Z dimensions refer to left-right, posterior-anterior, and ventral-dorsal respectively. So 38x-64x58mm refers to a point in right posterior dorsal region of the brain.


NEXT TIMEIngram §3: Neuroanatomy of language, any leftovers

☞ Go over questions at end of chapter.


neuroanatomy of language 2 sept 13, 2013 – day 10

Documents

brain languageling

lh of righthanders

latin word

dorsal fin dorsal

right left

good way

cerebral dominance

carotid amytal test