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					    Welcome to the fMRI courses.




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FMRI – Week 1 – Introduction    Scott Huettel, Duke University
                          An Introduction to
                           Functional MRI
                          FMRI Undergraduate Course (PSY 181F)
                         FMRI Graduate Course (NBIO 381, PSY 362)

                               Dr. Scott Huettel, Course Director



FMRI – Week 1 – Introduction                                        Scott Huettel, Duke University
                     Some Introductions: People

                               Course Director (Both Courses):
                               Scott Huettel
                               Associate Professor, Psychiatry, BIAC, CCN
                               Research Interests: Decision making, neuroeconomics



                               Teaching Assistants (Undergraduate Course):
                               Simon Davis
                               Graduate Student, Psychology & Neuroscience
                               Research Interests: Memory, neural connectivity

                               Melissa Libertus
                               Graduate Student, Psychology & Neuroscience
                               Research Interests: Development of numerical cognition



FMRI – Week 1 – Introduction                                                     Scott Huettel, Duke University
                      Some Introductions: Places

  Duke-UNC                                          Offices and Analysis Laboratory,
                                                                        Bell Building
  Brain Imaging &
  Analysis Center (BIAC)




                   www.biac.duke.edu


                                       MRI Scanners (3T, 4T), Duke Hospital
FMRI – Week 1 – Introduction                                  Scott Huettel, Duke University
                   Overview of the Course(s)
                   Undergraduate                                            Graduate
   •     Lectures                                          •   Lectures
           –   Wednesdays 3-4:30pm                              –   Wednesdays 3-4:30pm
           –   Room: 3031 Purple Zone, Duke Clinics             –   Room: 3031 Purple Zone, Duke Clinics

   •     Readings                                          •   Readings
           –   Functional Magnetic Resonance                    –   Functional Magnetic Resonance
               Imaging (Huettel, Song, McCarthy)                    Imaging (Huettel, Song, McCarthy)
           –   Original papers, posted to website               –   Original papers, posted to website

   •     Laboratories                                      •   Laboratories
           –   Introduction: Wed. 4:30-5:30pm                   –   Times arranged with TAs and
           –   Other times arranged with TAs                        instructor (group)

   •     Grading Basis                                     •   Grading Basis
           –   Attendance                                       –   Attendance
           –   Weekly laboratory exercises (group)              –   Weekly laboratory exercises (group)
           –   Short Quizzes                                    –   Self-assessment exercises
           –   Mid-term examination                             –   Mid-term examination
           –   Project presentation (group)                     –   Project presentation (group)
           –   Project final report (individual)


                               Course auditors are welcome to attend lectures!
FMRI – Week 1 – Introduction                                                         Scott Huettel, Duke University
                               Course Textbook

                                       • First edition (2004): Required
                                           –   Available at bookstore


                                       • Selected chapters from new
                                         edition (2008) will be provided by
                                         instructor

                                       • Self-assessment questions
                                         available on accompanying CD
                                           –   Graduates: Required
                                           –   Undergrads: Highly recommended




FMRI – Week 1 – Introduction                                     Scott Huettel, Duke University
                               Each week has lecture and laboratory components


                               Labs start next week and run from Thursday to
                               Tuesday; TAs will schedule.




                               We will introduce the analysis package FSL in a
                               combined session in this room.



                               The midterm for both classes is on 10/17. Different
                               exams, same time. Auditors welcome to take it for fun.

                               In late October, you will form small groups for your fMRI
                               projects. We’ll go over the project phase of the course
                               in great detail around then.




                               The last undergraduate session is a panel discussion; it is
                               optional for graduate students.

                               More info about the project presentations forthcoming.

FMRI – Week 1 – Introduction                                      Scott Huettel, Duke University
                                Course logistics…
                               or “What you need to do!”
       1.         Get a BIAC account and laboratory access
              –        TAs need your name, DukeID, etc.
              –        Gives you access to BIAC computer labs and servers

       2.         Arrange laboratory times with TAs
              –        Undergrads: Give them your schedule, and they will coordinate the
                       groups and laboratories
              –        Graduates: Sort into groups of up to 4, pick a day and time, and
                       then ask the TAs about availability
              –        These times will also be used for data collection and analysis on
                       your projects

       3.         Download course materials from the class website:
                  http://www.biac.duke.edu/education/courses/fall07/fmri/
                  (all materials will also be available on BlackBoard)




FMRI – Week 1 – Introduction                                                Scott Huettel, Duke University
                               Any questions?




FMRI – Week 1 – Introduction                    Scott Huettel, Duke University
                                   Outline for Today
       • Lecture: Introducing fMRI
              –    What is fMRI?
              –    History
              –    Key concepts
              –    Parts of a MR scanner
              –    MR safety

       • Laboratory: Scanner Visit (Dr. Jim Voyvodic)
              – Scanner hardware
              – Stimulus presentation and recording hardware
              – Demonstration of real-time fMRI
                               Note: I will post all slides to the course web page!
FMRI – Week 1 – Introduction                                                          Scott Huettel, Duke University
                               1. What is fMRI ?




FMRI – Week 1 – Introduction                       Scott Huettel, Duke University
                                     isn’t
                               1. What is fMRI ?




FMRI – Week 1 – Introduction                       Scott Huettel, Duke University
                               fMRI is not bumpology




FMRI – Week 1 – Introduction                           Scott Huettel, Duke University
                                                       • Phrenology claimed that
                                                         bumps on the skull reflected
                                                         exaggerated functions/traits

                                                       • It lacked any mechanism
                                                         underlying its claims.

                                 from Gall (c. 1810)
                                                       • It used anecdotal, rather than
                                                         scientific, evidence.

                                                       • Nevertheless, its central idea
                                                         persisted:
                                                         Localization of Function
     Franz Joseph Gall         Johann Spurzheim
       (1758-1828)                (1776-1832)



FMRI – Week 1 – Introduction                                                Scott Huettel, Duke University
                           fMRI is not mind-reading




                                                                    This is not a
                                                                     thought.




                               This is not a thought.
                                                        This is not a thought.


FMRI – Week 1 – Introduction                                     Scott Huettel, Duke University
          fMRI is not a window on the brain


                                      ―Mirror neuron activity in the right posterior
                                            inferior frontal gyrus – indicating
                                      identification and empathy - while watching
                                                   the Disney/NFL ad.‖



                               rIFG



                                               ―Ventral striatum activity – indicating
                                      vent
                                                reward processing - while watching
                                       Str             the Disney/NFL ad.‖




                                                   [Citations omitted to protect the offenders.]

FMRI – Week 1 – Introduction                                                Scott Huettel, Duke University
                                 fMRI is not invasive
                                                         Positron Emission
                                                         Tomography (PET)




                                     Intracranial
                               Stimulation / Recording

FMRI – Week 1 – Introduction                                    Scott Huettel, Duke University
              FMRI is… a technique for measuring
            metabolic correlates of neuronal activity

       • Uses a standard MRI scanner
       • Acquires a series of images (numbers)
       • Measures changes in blood oxygenation
       • Use non-invasive, non-ionizing radiation
       • Can be repeated many times; can be used for a wide
         range of subjects
       • Combines good spatial and reasonable temporal
         resolution




FMRI – Week 1 – Introduction                        Scott Huettel, Duke University
              fMRI is a Measurement Technique…

                               Manipulation Techniques

                               Lesions, TMS, Stimulation




                      BRAIN                                BEHAVIOR



                               Measurement Techniques
                                   fMRI, PET, EEG
FMRI – Week 1 – Introduction                                  Scott Huettel, Duke University
            … that provides information about a
                   wide range of topics.

       From what we see…                             … to what we feel.
   (ocular dominance columns)                 (the dread of an upcoming shock)




    Cheng, Waggoner, & Tanaka (2001) Neuron           Berns et al. (2006) Science
FMRI – Week 1 – Introduction                                            Scott Huettel, Duke University
                               2. History of fMRI



FMRI – Week 1 – Introduction                    Scott Huettel, Duke University
                          Timeline of MR Imaging
                                                                                           1972 – Damadian
         1924 - Pauli     1937 – Rabi measures                                            patents idea for large
        suggests that      magnetic moment of                                               NMR scanner to
      nuclear particles      nucleus. Coins                                                 detect malignant             1985 – Insurance
      may have angular    “magnetic resonance”.                                                   tissue.               reimbursements for
      momentum (spin).                                                                                                   MRI exams begin.

                                                                                                  1973 – Lauterbur            MRI scanners
                                         1944 – Rabi wins                                       publishes method for        become clinically
                                          Nobel prize in                                          generating images            prevalent.
                                             Physics.                                           using NMR gradients.
                                                       1952 – Purcell and
                                                       Bloch share Nobel




         M                                        R
                                                         prize in Physics.                                   NMR becomes MRI




          1920            1930          1940            1950               1960                 1970               1980             1990             2000

                                                                                                   1973 – Mansfield                 1990 – Ogawa and
                                                                                                     independently                   colleagues create
                                       1946 – Purcell shows                                        publishes gradient               functional images
                                       that matter absorbs            1959 – Singer                 approach to MR.                 using endogenous,
                                       energy at a resonant         measures blood flow
                                                                                                                                    blood-oxygenation
                                            frequency.                using NMR (in
                                                                                                                                          contrast.
                                                                          mice).
                                                                                                       1975 – Ernst
                                                                                                   develops 2D-Fourier
                                      1946 – Bloch demonstrates
                                                                                                    transform for MR.
                                      that nuclear precession can
                                        be measured in detector
                                                 coils.



FMRI – Week 1 – Introduction                                                                                                          Scott Huettel, Duke University
                               Early Uses of NMR

       • Most early NMR was used for chemical analysis
              – No medical applications

       • 1971 – Damadian publishes and patents idea for using
         NMR to distinguish healthy and malignant tissues
              – “Tumor detection by nuclear magnetic resonance”, Science
              – Proposes using differences in relaxation times
              – No image formation method proposed

       • 1973 – Lauterbur describes projection method for
         creating NMR images
              – Mansfield (1973) independently describes similar approach



FMRI – Week 1 – Introduction                                      Scott Huettel, Duke University
                     The First ZMR NMR Image




      Lauterbur, P.C. (1973). Image formation by induced local interaction: Examples employing nuclear magnetic resonance. Nature, 242, 190-191.


FMRI – Week 1 – Introduction                                                                                            Scott Huettel, Duke University
        Early Human MR
       Images (Damadian)




FMRI – Week 1 – Introduction   Scott Huettel, Duke University
                               Mink5 Image – Damadian (1977)
FMRI – Week 1 – Introduction                      Scott Huettel, Duke University
              Digression: 2003 Nobel Controversy




            Paul Lauterbur            Peter Mansfield
FMRI – Week 1 – Introduction                 Scott Huettel, Duke University
                               Raymond Damadian

FMRI – Week 1 – Introduction                      Scott Huettel, Duke University
      New York Times
      October 9, 2003




FMRI – Week 1 – Introduction   Scott Huettel, Duke University
      Nobel Press Release
      October 6, 2003

       Summary
       Imaging of human internal organs with exact and non-invasive methods is very important for medical diagnosis,
       treatment and follow-up. This year's Nobel Laureates in Physiology or Medicine have made seminal discoveries
       concerning the use of magnetic resonance to visualize different structures. These discoveries have led to the
       development of modern magnetic resonance imaging, MRI, which represents a breakthrough in medical
       diagnostics and research. …


       This year's Nobel Laureates in Physiology or Medicine are awarded for crucial achievements in the development of
       applications of medical importance. In the beginning of the 1970s, they made seminal discoveries concerning the
       development of the technique to visualize different structures. These findings provided the basis for the
       development of magnetic resonance into a useful imaging method.

       Paul Lauterbur discovered that introduction of gradients in the magnetic field made it possible to create two-
       dimensional images of structures that could not be visualized by other techniques. In 1973, he described how
       addition of gradient magnets to the main magnet made it possible to visualize a cross section of tubes with ordinary
       water surrounded by heavy water. No other imaging method can differentiate between ordinary and heavy water.

       Peter Mansfield utilized gradients in the magnetic field in order to more precisely show differences in the
       resonance. He showed how the detected signals rapidly and effectively could be analysed and transformed to an
       image. This was an essential step in order to obtain a practical method. Mansfield also showed how extremely rapid
       imaging could be achieved by very fast gradient variations (so called echo-planar scanning). This technique became
       useful in clinical practice a decade later.




FMRI – Week 1 – Introduction                                                                            Scott Huettel, Duke University
                              Timeline of MR Imaging
                                                                                                  1972 – Damadian
     1924 - Pauli suggests     1937 – Rabi measures                                              patents idea for large
     that nuclear particles     magnetic moment of                                                 NMR scanner to
       may have angular           nucleus. Coins                                                   detect malignant             1985 – Insurance
      momentum (spin).         “magnetic resonance”.                                                     tissue.               reimbursements for
                                                                                                                                MRI exams begin.

                                                                                                         1973 – Lauterbur           MRI scanners
                                               1944 – Rabi wins                                        publishes method for        become clinically
                                                Nobel prize in                                           generating images            prevalent.
                                                   Physics.                                            using NMR gradients.
                                                              1952 – Purcell and
                                                               Bloch share Nobel




         M                                             R                                                      I                                     f
                                                                prize in Physics.                                   NMR becomes MRI




           1920               1930           1940             1950                1960                 1970               1980             1990            2000

                                                                                                          1973 – Mansfield                1990 – Ogawa and
                                                                                                            independently                  colleagues create
                                             1946 – Purcell shows                                         publishes gradient              functional images
                                              that matter absorbs            1959 – Singer                 approach to MR.                using endogenous,
                                              energy at a resonant         measures blood flow
                                                                                                                                          blood-oxygenation
                                                   frequency.                using NMR (in
                                                                                                                                               contrast.
                                                                                 mice).
                                                                                                              1975 – Ernst
                                                                                                          develops 2D-Fourier
                                            1946 – Bloch demonstrates
                                                                                                           transform for MR.
                                          that nuclear precession can be
                                            measured in detector coils.




FMRI – Week 1 – Introduction                                                                                                                 Scott Huettel, Duke University
                 Physiology (BOLD Contrast)



                               Blood-Oxygenation-
                                Level Dependent
                                    contrast




FMRI – Week 1 – Introduction                        Scott Huettel, Duke University
                      Using MRI to Study Brain Function




          Kwong, et al., 1992                    Visual Cortex


FMRI – Week 1 – Introduction                           Scott Huettel, Duke University
                Growth in fMRI : Published Studies
     1990

     1991

     1992

     1993

     1994
                                              Medline search on “functional magnetic
     1995
                                             resonance”, “functional MRI”, and “fMRI”.
     1996
                                               Year 2004 = ~1500; Years 2005+ > 2000
     1997

     1998

     1999

     2000

     2001

     2002

     2003

     2004                                                                          …
            0              200   400   600   800          1000         1200               1400


FMRI – Week 1 – Introduction                                          Scott Huettel, Duke University
                               3. Key Concepts



FMRI – Week 1 – Introduction                     Scott Huettel, Duke University
                               Key Concepts

       •     Contrast
       •     Spatial Resolution
       •     Temporal Resolution
       •     Functional Resolution




FMRI – Week 1 – Introduction                  Scott Huettel, Duke University
                    Contrast: Conceptual Overview




FMRI – Week 1 – Introduction                  Scott Huettel, Duke University
                               Contrast: Anatomical




        Contrast:
           1) An intensity difference between quantities: “How much?”
           2) The quantity being measured: “What?”
        Contrast-to-noise: The magnitude of the intensity difference between quantities
           divided by the variability in their measurements.


FMRI – Week 1 – Introduction                                                   Scott Huettel, Duke University
                               Contrast: Functional




           Contrast-to-noise is critical for fMRI: How effectively can we decide
               whether a given brain region has property X or property Y?
FMRI – Week 1 – Introduction                                        Scott Huettel, Duke University
                    Spatial Resolution: Voxels




                   Voxel: A small rectangular prism that is the basic sampling unit of fMRI.
                    Typical anatomical voxel: (1.5mm)3. Typical functional voxel: (4mm)3.
FMRI – Week 1 – Introduction                                                         Scott Huettel, Duke University
                        Spatial Resolution: Examples




      ~8mm2                              ~4mm2           ~2mm2




                               ~1.5mm2           ~1mm2

FMRI – Week 1 – Introduction                                     Scott Huettel, Duke University
                               Temporal Resolution
           • Determining factors
                  – Sampling rate, usually repetition time (TR)
                  – Dependent variable, usually BOLD response
                         • BOLD response is sluggish, taking 2-3 seconds to rise above baseline
                           and 4-6 seconds to peak
                  – Experimental design

           • Most FMRI studies have temporal resolution on the order of a
             few seconds
                  – With specialized designs and data acquisition, this can be
                    improved to ~100ms




FMRI – Week 1 – Introduction                                                         Scott Huettel, Duke University
FMRI – Week 1 – Introduction   Scott Huettel, Duke University
FMRI – Week 1 – Introduction   Scott Huettel, Duke University
                               Functional Resolution

           The ability of a measurement technique to identify the
            relation between underlying neuronal activity and a
                    cognitive or behavioral phenomenon.

             Functional resolution is limited both by the intrinsic
            properties of our brain measure and by our ability to
            manipulate the experimental design to allow variation
                       in the phenomenon of interest.




FMRI – Week 1 – Introduction                               Scott Huettel, Duke University
                               4. MRI Scanners



FMRI – Week 1 – Introduction                     Scott Huettel, Duke University
                 GE 3T Scanner (cf. BIAC’s)

FMRI – Week 1 – Introduction                  Scott Huettel, Duke University
         Phillips 3T Scanner (Vanderbilt)
                                                     Siemens 3T Scanner




                                                          FONAR 0.6T MR
                        Phillips 0.6T Open Scanner        Operating Room

FMRI – Week 1 – Introduction                                     Scott Huettel, Duke University
           Main Components of a Scanner

       1. Magnetic: Static Magnetic Field Coils
       2. Resonance: Radiofrequency Coil
       3. Imaging: Gradient Field Coils

       •         Shimming Coils
       •         Data transfer and storage computers
       •         Physiological monitoring, stimulus display,
                 and behavioral recording hardware


FMRI – Week 1 – Introduction                           Scott Huettel, Duke University
                      1. Magnetic: Static Field Coils



          The scanner contains large parallel
                  coilings of wires.
      These generate the main magnetic field
       (B0), which gives the scanner its field
                strength (e.g., 3T).




FMRI – Week 1 – Introduction                       Scott Huettel, Duke University
             2. Resonance: Radiofrequency Coils
                   Surface Coil   Volume Coil




                                                Electronic coils tuned
                                                 to radio signals send
                                                 energy into the brain
                                                and record an emitted
                                                       ―echo‖.




FMRI – Week 1 – Introduction                           Scott Huettel, Duke University
                               3. Imaging: Gradient Coils




                                                    Three gradient coils are
                                                    used, one in each of the
                                                      cardinal directions.
                                                       These allow spatial
                                                    encoding of the MR signal.




FMRI – Week 1 – Introduction                                 Scott Huettel, Duke University
                                The scanner is
                               controlled by a
                               pulse sequence.


FMRI – Week 1 – Introduction     Scott Huettel, Duke University
                                      Pulse Sequences



                    T1


                      T2

                               • Recipes for controlling scanner hardware
                               • Allow MR to be extremely flexible
FMRI – Week 1 – Introduction                                                Scott Huettel, Duke University
   5. MRI Safety

FMRI – Week 1 – Introduction   Scott Huettel, Duke University
           Hospital Nightmare
           Boy, 6, Killed in Freak MRI Accident

                July 31, 2001 — A 6-year-old boy died
                after undergoing an MRI exam at a New
                York-area hospital when the machine's
                powerful magnetic field jerked a metal
                oxygen tank across the room, crushing the
                child's head. …


                                                  ABCNews.com
FMRI – Week 1 – Introduction                        Scott Huettel, Duke University
                                   MR Incidents
           • Pacemaker malfunctions leading to death
                  – At least 5 as of 1998 (Schenck, JMRI, 2001)
                  – E.g., in 2000 an elderly man died in Australia after being twice
                    asked if he had a pacemaker

           • Blinding due to movements of metal in the eye
                  – At least two incidents (1985, 1990)

           • Dislodgment of aneurysm clip (1992)

           • Projectile injuries (most common incident type)
                  – Injuries (e.g., cranial fractures) from oxygen canister (1991, 2001)
                  – Scissors hit patient in head, causing wounds (1993)

           • Gun pulled out of policeman’s hand, hitting wall and firing
                  – Rochester, NY (2000)

FMRI – Week 1 – Introduction                                                Scott Huettel, Duke University
                               Issues in MR Safety
           • Known acute risks
                  – Projectiles, rapid field changes, RF heating,
                    claustrophobia, acoustic noise, etc.

           • Potential acute/chronic risks
                  – Current induction in tissue at high fields?
                  – Changes in the developing brain?

           • Epidemiological studies of chronic risks
                  – Extended exposure to magnetic fields does not cause harm

           • Difficulty in assessing subjective experience
                  – In one study, 45% of subjects exposed to a 4T scanner
                    reported unusual sensations (Erhard et al., 1995)

FMRI – Week 1 – Introduction                                         Scott Huettel, Duke University
                 Projectile Effects: External



                               The Scanner
                               is Never Off!
                                                                               Chaljub (2001)




               Schenck (1996)

     “Large ferromagnetic objects that were reported as having been
     drawn into the MR equipment include a defibrillator, a wheelchair, a
     respirator, ankle weights, an IV pole, a tool box, sand bags containing
     metal filings, a vacuum cleaner, and mop buckets.”
     -Chaljub et al., (2001) AJR
                                                                                                Chaljub (2001)
FMRI – Week 1 – Introduction                                                               Scott Huettel, Duke University
FMRI – Week 1 – Introduction   Scott Huettel, Duke University
                               Any questions?




FMRI – Week 1 – Introduction                    Scott Huettel, Duke University
                               BIAC Scanner Tour
   •     Dr. Jim Voyvodic will demonstrate real-time fMRI
           –   We will see the 3T BIAC scanner in action
           –   Go through the mock scanner

   •     You’ll go through low-field areas of the MR center
           –   Anyone with pacemaker, other implanted metal (shunts,
               clips, etc.) should tell instructor
           –   Fillings, piercings fine (for console room)
           –   Please be considerate while walking through the hospital!

   •     We’ll travel in groups
           –   Undergraduates: Go now with Simon Davis
           –   Graduates: Go with Melissa Libertus momentarily
           –   Auditors: Go with Scott Huettel, after the other groups




FMRI – Week 1 – Introduction                                               Scott Huettel, Duke University
FMRI – Week 1 – Introduction   Scott Huettel, Duke University
                          Timeline of MR Imaging
                                                                                           1972 – Damadian
         1924 - Pauli     1937 – Rabi measures                                            patents idea for large
        suggests that      magnetic moment of                                               NMR scanner to
      nuclear particles      nucleus. Coins                                                 detect malignant             1985 – Insurance
      may have angular    “magnetic resonance”.                                                   tissue.               reimbursements for
      momentum (spin).                                                                                                   MRI exams begin.

                                                                                                  1973 – Lauterbur            MRI scanners
                                         1944 – Rabi wins                                       publishes method for        become clinically
                                          Nobel prize in                                          generating images            prevalent.
                                             Physics.                                           using NMR gradients.
                                                       1952 – Purcell and
                                                       Bloch share Nobel
                                                         prize in Physics.                                   NMR becomes MRI




          1920            1930          1940            1950               1960                 1970               1980             1990             2000

                                                                                                   1973 – Mansfield                 1990 – Ogawa and
                                                                                                     independently                   colleagues create
                                       1946 – Purcell shows                                        publishes gradient               functional images
                                       that matter absorbs            1959 – Singer                 approach to MR.                 using endogenous,
                                       energy at a resonant         measures blood flow
                                                                                                                                    blood-oxygenation
                                            frequency.                using NMR (in
                                                                                                                                          contrast.
                                                                          mice).
                                                                                                       1975 – Ernst
                                                                                                   develops 2D-Fourier
                                      1946 – Bloch demonstrates
                                                                                                    transform for MR.
                                      that nuclear precession can
                                        be measured in detector
                                                 coils.



FMRI – Week 1 – Introduction                                                                                                          Scott Huettel, Duke University
           Rabi and the Measurement of the Nuclear
                   Magnetic Moment (1937)




FMRI – Week 1 – Introduction                Scott Huettel, Duke University
                      Discovery of Nuclear Magnetic
                      Resonance Absorption (1946)
                                                • Bloch and Purcell independently
                                                  discovered how to measure
                                                  nuclear moment of bulk matter
                                                  (1946)

                                                • They showed that energy
                                                  applied at a resonant frequency
       Felix Bloch                                was absorbed by matter, and
                                                  the re-emission could be
                                                  measured in detector coils

                                                • They shared the 1952 Nobel
                               Edward Purcell
                                                  Prize in Physics


FMRI – Week 1 – Introduction                                         Scott Huettel, Duke University
                              Timeline of MR Imaging
                                                                                          1972 – Damadian
     1924 - Pauli suggests     1937 – Rabi measures                                        patents idea for
     that nuclear particles     magnetic moment of                                       large NMR scanner
       may have angular           nucleus. Coins                                         to detect malignant          1985 – Insurance
      momentum (spin).         “magnetic resonance”.                                            tissue.              reimbursements for
                                                                                                                      MRI exams begin.

                                                                                               1973 – Lauterbur            MRI scanners
                                               1944 – Rabi wins                              publishes method for        become clinically
                                                Nobel prize in                                 generating images            prevalent.
                                                   Physics.                                  using NMR gradients.
                                                              1952 – Purcell and
                                                               Bloch share Nobel
                                                                prize in Physics.                        NMR becomes MRI




           1920               1930           1940             1950              1960          1970             1980              1990             2000

                                                                                                1973 – Mansfield                 1990 – Ogawa and
                                                                                                  independently                   colleagues create
                                             1946 – Purcell shows                               publishes gradient               functional images
                                              that matter absorbs        1959 – Singer          approach to MR.                  using endogenous,
                                              energy at a resonant     measures blood flow
                                                                                                                                 blood-oxygenation
                                                   frequency.            using NMR (in
                                                                                                                                       contrast.
                                                                             mice).
                                                                                                   1975 – Ernst
                                                                                                   develops 2D-
                                            1946 – Bloch demonstrates
                                                                                                 Fourier transform
                                          that nuclear precession can be
                                                                                                     for MR.
                                            measured in detector coils.




FMRI – Week 1 – Introduction                                                                                                       Scott Huettel, Duke University

				
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