Chapter 2: PowerPoint

1
Chapter 2 PowerPoint 2Brain Imaging Techniques

• CT Scan Computerized Axial Tomography
• MRI Magnetic Resonance Imaging
• fMRI Functional Magnetic Resonance Imaging
• PET Scan Positron Emission Tomography Scan
• EEG Electroencephalograph

2
CT Scans An x-ray of the brain.
A CT scan is essentially a computerized assembly
of several x-ray images taken from a series of
different angles. With a CT, the resolution is
much better than conventional x-rays, and the
detail that can be seen is much greater. 
3
Tumor in Wernickes Area
        MRI is a noninvasive imaging technique
that does not use x-rays.   The process involves
passing a strong magnetic field through the
head.  The magnetic field used is 30,000 times
that of the earth's magnetic field.  It's effect
on the body, however, is harmless and temporary. 
The MRI scanner can detect radiation from certain
molecules, which are present in different
concentrations in different tissues. 
4
P E T S C A N S
PET measures the emission of positrons from the
brain after a small amount of radioactive
isotopes, or tracers,  have been injected into
the blood stream.  A common example is a
glucose-relative with embedded fluor-18.   With
this molecule, the activity of different regions
of the brain can be measured.  The result is a
three-dimentional map with the brain activity
represented by colors. 
5
Dopamine
P E T S C A N S
Normal Brain ADHD Brain
After Implant of Dopamine-secreting Tissue
Brain Development in First Year of Life
6
EEG of Mouse with Epileptic Seizure
EEG Cap
Alert
Deep Sleep
7
The Evolution of the Brain
8
(No Transcript)
9
THALAMUS
10
CEREBELLUM
Alcoholism causes brain shrinkage to the
cerebellum
11
(No Transcript)
12
Emotion and Memory are closely connected.
Amygdala A little almond shaped structure,
connects with the hippocampus.
Hippocampus Is particularly involved with memory
phenomena, specially with the formation of
long-term memory (the one that, sometimes, lasts
forever).
13
The pituitary gland may be king, but the power
behind the throne is clearly the hypothalamus.
14
Lobes of the Cerebral Cortex
15
Motor Area
Sensory Area
16
LANGUAGE CENTERS
Disrupts Understanding
Disrupts Speaking
Speaking the Heard Word
Speaking the Written Word
Angular Gyrus
Speak Understand, Unable to Read
17
(No Transcript)