Functional Magnetic Resonance Imaging of the Brain

Abstract

Functional magnetic resonance imaging of the brain is becoming a popular diagnostic tool for evaluating the physiology of cognition, emotion, creativity, memory, neurobiology, psychiatry and observing how a normal, versus diseased or injured brain is working. The purpose of this literature review is to summarize research and clinical trial on Functional magnetic imaging of the brain. Several peer reviewed articles are presented with their hypothesis, methods and results. Because functional brain imaging is a fairly new diagnostic tool, much of it applications are still in the trail process. This paper will examine and provide insight into the methodology of functional brain imaging as well as explaining the contrast mechanism, clinical applications and future developments of this imaging process.

Table of Content

ABSTRACTII

I. INTRODUCTION1

a)What is FMRI1

b)History of FMRI8

c) Explicit And Implicit Memory9

d) Neuroimaging Techniques And Typical Measurements Of Repetition Priming11

II.LITERATURE REVIEW12

a)Dynamic imaging of brain12

Pre-Processing12

Motion Correction12

Distortion Correction13

De-Noising And Drift Estimation13

Anatomical Registration13

Functional Registration14

b)Neuronal activity - brain mapping14

Modeling14

Estimation15

Functional Specialization15

Unsupervised15

Cluster-Analysis15

Decomposition16

Mass Univariate16

Chronometry Methods18

Functional imaging, metabolic and vascular brain by Nuclear Magnetic Resonance20

III.BOLD FMRI21

b)Contrast mechanism/ Pulse sequences24

Mri Equipment26

Echo Planar Imaging27

IV.DISCUSSION28

a)Cognitive neuroscience28

b)Psychology30

c)Neurobiology31

d)Psychiatry31

e)Radiology and more32

V.FUTURE DEVELOPMENTS34

a)Clinical research34

b)Advancements34

Functional Connectivity34

Decomposition35

Cross-Correlation35

VI. CONCLUSION36

REFERENCES37

Functional Magnetic Resonance Imaging (fMRI) of the Brain

I. INTRODUCTION

Our desire to understand the inner workings of the brain has led scientific researchers to phenomenal ends. Thoughts, emotions, conscious or unconscious functions of the brain, or a diseased brain can now be explored through functional imaging. One such imaging process is known as functional magnetic resonance imaging (fMRI). Advancements in magnetic resonance imaging (MRI) technology has allowed for fast imaging sequences which has made fMRI possible. Functional MRI is now one of physician's best tools in diagnostic imaging for cognitive neuroscience, psychology, neurobiology, psychiatry and observing how a normal, diseased or injured brain is working (Huettel, Song, & McCarthy, 2004). Functional MRI is also useful for evaluating tissue vitality in cases of ischemia diseases for stroke, trauma or Alzheimer's (Huettel, Song, & McCarthy, 2004). It can be used for monitoring brain tumors and assessing patients for the potential risk of surgery or other invasive treatments of the brain (Huettel, Song, & McCarthy, 2004). Several case studies have been performed to evaluation the validity of functional MRI as a diagnostic tool for brain imaging.

a)What is FMRI

fMRI is a rapid magnetic resonance imaging technique that acquires images of the brain during activity or stimulus and at rest” (Westbrook, Roth & Talbot, 2009). Functional MRI works by obtain signals from metabolism and blow flow of tissues in our brain and creating images. The different rates and level of oxygenation in the blood provides the contrast needed for distinction of various brain functions. Hemoglobin is an iron containing protein in red blood cells that transport oxygen all around the body. . Oxyhemoglobin is the product of combining oxygen with hemoglobin, and deoxyhemoglobin is the form of hemoglobin without oxygen. Because there is iron in hemoglobin, blood is considered a paramagnetic agent used for MRI imaging. Using the different levels of blood flow and oxygenation eliminates the need for injections of radioactive ...