Download - The Brain in MRI and CT
![Page 1: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/1.jpg)
![Page 2: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/2.jpg)
![Page 3: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/3.jpg)
![Page 4: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/4.jpg)
The Brain in MRI and CT
•MRI are taken by a rotating magnetic field
• CT scans are taken by rotating X-ray source
![Page 5: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/5.jpg)
Always Your Right is the Patient’s Left
You
Coronal
Axial
You
Patient
Patient
In axial MRI , you looking from down to top, as if you look to the patient from the feet “see demonstration”In coronal MRI, you looking to the patient face to face.
![Page 6: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/6.jpg)
![Page 7: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/7.jpg)
![Page 8: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/8.jpg)
![Page 9: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/9.jpg)
![Page 10: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/10.jpg)
![Page 11: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/11.jpg)
![Page 12: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/12.jpg)
Ventral “What” pathway
![Page 13: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/13.jpg)
Ventral “What” pathway
• Carries information about static object properties such as colour, luminance, stereopsis and pattern recognition.
• Slow pathway from P-ganglion cells (through laminae 3-6 of LGN, V1) to V2, V4 and inferior temporal cortex
![Page 14: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/14.jpg)
Dorsal “Where” pathway
![Page 15: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/15.jpg)
Dorsal “Where” pathway
• Information about dynamic object properties- motion and spatial
relationships
• Fast pathway for transient visual signals
• Pathway to V1, V2, MT, medial superior temporal and parietal lobe
![Page 16: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/16.jpg)
![Page 17: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/17.jpg)
David van Essen
![Page 18: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/18.jpg)
![Page 19: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/19.jpg)
![Page 20: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/20.jpg)
![Page 21: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/21.jpg)
![Page 22: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/22.jpg)
Visual processing of information
![Page 23: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/23.jpg)
![Page 24: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/24.jpg)
Damage to “What” pathway
Achromatopsia, agnosia
![Page 25: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/25.jpg)
Achromatopsia
• Complete achromatopsia- BL
area V4: Lingual/fusiform
gyri/occipitotemporal junction
![Page 26: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/26.jpg)
Color agnosia
• Color agnosia: loss the ability
to retrieve color knowledge
• cannot name colors for objects
but can sort
• Remembering the color of
object
• Color composition
Left or bilateral occipitotemporal region Inferior temporal , fusiform and right lingual
![Page 27: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/27.jpg)
Color anomia• Inability to name colors or to
point to colors given their names, which is not due to aphasia or due to defective color perception
![Page 28: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/28.jpg)
Color anomia
• Usually associated with left mesial occipitotemporal region
• hence usually affect the visual cortex or optic rediation leading to right hemianopia , and also associated with alexia
• Inability to name colors or to point to colors given their names, which is not due to aphasia or due to defective color perception
![Page 29: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/29.jpg)
![Page 30: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/30.jpg)
The Neural Basis of Visual Perception
• Visual agnosia is the inability to recognize objects despite satisfactory vision.– Caused by damage to the pattern pathway
usually in the temporal cortex. – For words : Alexia
![Page 31: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/31.jpg)
Agnosia
• Topographagnosia– Inability to navigate routes using familiar landmarks -
deficit in familiar scene perception– Right lingual gyrus
• Alexia– Left (dominant lobe) fusiform/lingual areas
![Page 32: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/32.jpg)
![Page 33: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/33.jpg)
Lesion, left occipitotemporal region and involves parts of the lingual and fusiform gyri.
Hemi- achromatopsia , pure alexia , and category-specific visual object agnosia
![Page 34: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/34.jpg)
Occipitotemporalgyri
![Page 35: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/35.jpg)
![Page 36: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/36.jpg)
Occipitotemporalgyri
![Page 37: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/37.jpg)
![Page 38: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/38.jpg)
Kanwisher , McDermott, and Chun, 1997
![Page 39: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/39.jpg)
Kanwisher , McDermott, and Chun, 1997
![Page 40: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/40.jpg)
![Page 41: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/41.jpg)
Agnosia
• Prosopagnosia- – Inability to recognize or
learn faces– Identify people by other
cues- gait, mannerisms or facial features- spectacles, gait
– Aware of defect– BL lingual and fusiform
gyri of medial occipitotemporal cortex.
![Page 42: The Brain in MRI and CT](https://reader035.vdocuments.us/reader035/viewer/2022081419/56813d03550346895da6a602/html5/thumbnails/42.jpg)