Brain anatomy tutorial. Dr. Michal Ben-Shachar 459 Neurolinguistics

Transcription

1 Brain anatomy tutorial Dr. Michal Ben-Shachar 459 Neurolinguistics

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3 The human brain Left hemisphere Right hemisphere

4 Zoom out

5 Zoom in

6 Types of Brain Tissue Gray Matter: Cell bodies (also short connections) White Matter: Axons which form pathways for conducting information between brain cells. Gray matter White matter

7 Gray matter, White matter Gray matter (stained purple): folded sheet containing cell bodies, dendrites, local axons collaterals. White matter: axons, long range connections.

8 Cerebrospinal Fluid (CSF) Located between the menings and in the ventricles of the brain Functions mechanical buffer fluid for metabolic functions "Copyright 2005 by Thompson Delmar Learning, a division of Thomson Learning, Inc. ALL RIGHTS RESERVED"

9 The hemispheres: Two brains for the price of one? Fiber tracts (White matter)

10 The hemispheres: Two brains for The hemispheres are connected through the corpus callosum the price of one? Cortex (Gray matter) The Virtual Hospital Fiber tracts (White matter)

11 Defining the lobes Frontal Central Sulcus Parietal Occipital Temporal Sylvian Fissure

12 Sylvian Fissure (or lateral sulcus) Separates temporal lobe from parietal and frontal lobes Sylvian Fissure

13 Middle Cerebral Artery

14 MCA stroke Radiopedia.org; contributed by Dr. Frank Gaillard, July 2010

15 Cortical Names Much of cortex referred to by combination of coordinate+lobe+gyrus E.G. Superior Temporal Gyrus (STG) Middle Temporal Gyrus(MTG) Lateral Occipital Gyrus (LOG)

16 Cortical names Tip of an object called a pole Frontal Pole Temporal Pole

17 Sulci names Many of sulci referred to by combination of coordinate+lobe+sulcus Superior temporal sulcus (STS) Inferior frontal sulcus (IFS) Precentral and postcentral sulci are just anterior and posterior to the central sulcus.

18 Superior and Inferior Frontal Sulci Superior Frontal Sulcus (red) -divides superior frontal gyrus (mocha) from middle frontal gyrus (pink) Inferior Frontal Sulcus (blue) -divides middle frontal gyrus from inferior frontal gyrus (gold) orbital gyrus (green) and frontal pole (gray) also shown

19 Superior and Inferior Temporal Sulci Superior Temporal Sulcus (red) -divides superior temporal gyrus (peach) from middle temporal gyrus (lime) Inferior Temporal Sulcus (blue) -not usually very continuous -divides middle temporal gyrus from inferior temporal gyrus (lavender)

20 Broca s Aphasia Identified 1861 by Paul Broca, a French neurologist Patient Leborgne: intelligent, good comprehension, severe deficit in speech production Dronkers et al., 2007 Leborgne died soon afterwards: brain showed selective damage to left inferior frontal gyrus

21 Broca s area Leborgne brain Lelong s brain

22 Wernicke s aphasia Identified 1873 by Carl Wernicke, a German neurologist Patient fluent, but very poor language comprehension Died soon afterwards: brain showed selective damage in rear parietal/temporal region, left hemisphere Wernicke s aphasia is sometimes termed fluent aphasia or sensory aphasia

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24 Brain slices Sagittal Axial Coronal

25 Views / slice directions 3 Common Views: Coronal (head on) Sagittal (profile) Axial (bird s eye), aka Transverse. coronal sagittal axial

26 Sagittal and Midsagittal A Sagittal slice down the midline is called the midsagittal view. midsagittal sagittal

27 Oblique Slices Slices that are not cut parallel to an orthogonal plane are called oblique. The oblique blue slice is neither Coronal nor Axial. Cor Oblique Ax

28 CT of a Broca s aphasic

29 CT of Wernicke s aphasic brain

30 Describing cortex location Brodmann Areas (BAs, 1909) Appearance of cortex under microscope Not necessarily reflect function Arbitrary numbers Of particular relevance: 44/45 Broca s Area 22 Wernicke s Area

31 Brodman s areas Cytoarchitectonically defined brain regions i.e., areas with the same physiological characteristics are grouped under a given number.