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Joy Hirsch, Ph.D., ProfessorDirector, fMRI Research Center
Columbia University Health Sciences NI Basement
www.fmri.org
Neuroscience 2003Functional Brain Imaging
Hirsch, J., et alColumbia fMRI
A. Hypothesis of functional specificity
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG6. Electroencephalography, EEG
C. Integration of Brain Mapping Techniques
A Brief Outline
A. Hypothesis of functional specificity
Hirsch, J., et alColumbia fMRI
1. Specializations of single brain areas
Page 2
Hirsch, J., et alColumbia fMRI
PrimaryVisual Cortex
FlashingLED Display
7 7
66
5
4 4
5
Calcarine Sulcus
PreviousSurgicallesion
BINOCULARFLASHING
LIGHTS
Left Eye Right Eye
Visual Field
Harrington, 1964
lesion
R
Hirsch, J., et alColumbia fMRI
HISTORICAL MILESTONES
1841
Aphasia and lesions in GFi
BROCA
1874
WERNICKE
Aphasia and lesions in GTs
1890
ROY & SHERRINGTONRelationship between neural activity and vascular changes
1909
BRODMANN
Cytoarchitectonic regions of cortex
1950
PENFIELDIntraoperative cortical maps
1845
FARADAYMagnetic properties of blood
1936
PAULINGMagnetic state of hemoglobin changes with oxygenationRABIDiscovery of Magnetic Resonance
1945
PURCELL BLOCK
Demonstrated NMR in condensed
matter
1971
HOUNSFIELD CORMACKInvention of Computed Tomography
Hirsch, J., et alColumbia fMRI
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Damasio, H., et al; Science 264: 1102-1105, 20 May 1994
Hirsch, J., et alColumbia fMRI
HISTORICAL MILESTONES
1977
TER-POGOSSIAN SOKOLOFF
First PET studies of brain metabolism, blood flow, and correlates of human behavior
MANSFIELD
1976
First MRI of a body part
Invented EPI (scans whole brain in secs.)
1972
LAUTERBUR
First MR image
OGAWA
Blood Oxygen dependent signal
EPI / MRI Behavior
BELLIVEAUCortical Map:human visual
system
1990
1992
fMRI1971
DAMADIAN
Discovered that biological tissues have different relaxation rates
Hirsch, J., et alColumbia fMRI
A. Hypothesis of functional specificity
Hirsch, J., et alColumbia fMRI
1. Specializations of single brain areas2. Specializations of multiple brain areas
Page 4
Functional Organization of Visual Cortex
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI
Sadek K. Hilal, M.D., Ph.D.Department of RadiologyColumbia University
Early Developments in MR Solved the Occluded-Structure Problem
Hirsch, J., et alColumbia fMRI
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R L
Hirsch, J., et alColumbia fMRI
2 minutes 24 seconds 2 minutes 24 seconds
- 40 s - - 40 s - - 40 s - - 40 s - - 40 s - - 40 s -
TIME
MR
I Sig
nal I
nten
sity
REST REST REST RESTTASK TASK
R L
From Hirsch, J., et al; An Integrated Functional Magnetic Resonance Imaging Procedure for Preoperative Mapping of Cortical Areas Associated with Tactile, Motor, Language, and Visual Functions, Neurosurgery 47: 711-722, 2000.
Current Developments in MR are focused on the structure/function problem
Left Hand - Touch
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI
a. Source of signal
Page 6
PHYSIOLOGY PHYSICSNEURAL ACTIVATIONIS ASSOCIATED WITH ANINCREASE IN BLOOD FLOW
O2 EXTRACTION ISRELATIVELY UNCHANGED
RESULT:REDUCTION IN THEPROPORTION OF DEOXY HGBIN THE LOCAL VASCULATURE
DEOXY HGBIS PARAMAGNETIC
AND DISTORTS THE LOCALMAGNETIC FIELD CAUSINGSIGNAL LOSS
RESULT:LESS DISTORTION OF THEMAGNETIC FIELD RESULTS IN LOCAL SIGNAL INCREASE
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRIa. Source of signalb. Measuremnet techniques
Imaging While Naming Objects
Hirsch, J., et alColumbia fMRI
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Block Design
Hirsch, J., et alColumbia fMRI
Event-Related Design
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRIa. Source of signalb. Measuremnet techniquesc. Computation for analysis
COMPUTATIONS FOR fUNCTIONAL IMAGE PROCESSING
RECONSTRUCTIONALIGNMENT
VOXEL BY VOXEL ANALYSIS
GRAPHICALREPRESENTATION
ScannerFunctionalBrain Map
PrimaryAuditory Cortex
Language
Hirsch, J., et alColumbia fMRI
Page 8
Penfield’sMotor
Homonculus
Left Hand: Finger Thumb Tapping
MULTI-STAGE ANALYSISWITH COINCIDENCE
Run 1(90 secs)
Run 2(90 secs)
Stage 1
Stage 2
1 and 2
COINCIDENCERun 1 AND Run 2
Hirsch, J., et alColumbia fMRI
R
Kim, Relkin, Lee, & Hirsch
+ +
+ +
0
“LATE” BILINGUAL(Separate Language Areas)
Native (English)Second (French)
+ Center-of-Mass
from Nature 388, 171-174 (1997)
Broca’s Area
R
++
++
0
Native 1 (Turkish)Native 2 (English)
Common Region+ Center-of-Mass
“EARLY” BILINGUAL(Overlapping Language Areas)
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRIa. Source of signalb. Measuremnet techniquesc. Computation for analysisd. Individual brain maps
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Before Surgery
R
Tumor
ConventionalImaging
Functional Imaging
CC 23 (AB)
Left Hand: Sensory/Motor
Tumor
Hirsch, J., et alColumbia fMRI
R
Tumor
ConventionalImaging
CC 23 (AB)
Hirsch, J., et alColumbia fMRI
Left HandMovement
Before Surgery After Surgery
R
Tumor
ConventionalImaging
Functional Imaging
CC 23 (AB)
Left Hand: Sensory/Motor
Tumor
Hirsch, J., et alColumbia fMRI
Page 10
SENSORYTouch
MOTORFinger Thumb
Tapping(active)
Standard Brain Mapping Tasks
PictureNaming
Listeningto Words
(passive)
GPoC GPrC GOi GTs
LANGUAGE
GFiGTT
(active)(passive)
From Hirsch, J., et al; Neurosurgery 47: 711-722, 2000
Hirsch, J., et alColumbia fMRI
Functional Organization of Visual Cortex
Hirsch, J., et alColumbia fMRI
QuickTime™ and a Video decompressor are needed to see this picture.
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation
Page 11
SSEP - SomatoSensory Evoked PotentialsCortical Stimulation
Conventional functional mapping in the OR
Based on Electrical Activity of Neurons Induced by External Stimulation
Hirsch, J., et alColumbia fMRI
Tag 3
Tag 5
Localization fMRISSEP
“Twitching in 1st three digits”
“Twitching of hand,
focal seizure involving arm ”
Direct Cortical StimulationCraniotomy
Sensory Motor Mapping
From Hirsch, J., et al; An Integrated Functional Magnetic Resonance Imaging Procedure for Preoperative Mapping of Cortical Areas Associated with Tactile, Motor, Language, and Visual Functions, Neurosurgery 47: 711-722, 2000.
Tag 3
Tag 5
Hirsch, J., et alColumbia fMRI
Hirsch, J., et alColumbia fMRI
Homonculus
Page 12
Language Mapping
From Hirsch, J., et al; An Integrated Functional Magnetic Resonance Imaging Procedure for Preoperative Mapping of Cortical Areas Associated with Tactile, Motor, Language, and Visual Functions, Neurosurgery 47: 711-722, 2000.
fMRIIntraoperative
Stimulation Response
Speech ArrestDuring Counting
Broca’s Area
Literal paraphasic
speech error during picture
naming
Wernicke’s Area
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET
a. Source of signal
Positron Emission TomographyRadionuclides that emit positrons such as 15O and 18F are introduced into the brain.
H215O behaves like H2
16O and indicates blood flow (rCBF) (half life = 123 seconds) integration time ≈ 60 seconds.
18F – deoxyglucose behaves like deoxyglucose and indicates metabolic activity (half-life = 110 minutes) integration time ≈ 20 minutes
From: www.epub.org.br/cm/n011pet/pet.htm
PET SCANNER
Hirsch, J., et alColumbia fMRI
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Principle of PET
From: Principles of Neural Science (4th. Ed.) Kandel, Schwartz, & Jessell, p. 377.
A2 Positron and electron annihilationand emission of gamma raysPET is based on the radioactive
decay of positrons from the nucleus of the unstable atoms (15O has 8 protons and 7 neutrons)
resolutionlimit
Electron
PositronUnstableradionuclide
0-9mm
Gamma ray
Site of positron annihilation (imaged point)
Gamma rayphoton
A1 Positron emissionin the brain
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET
a. Source of signalb. Measurement techniques
Gamma Ray Detections to Location of Function
From: Principles of Neural Science (4th. Ed.) Kandel,Schwartz, & Jessell, p. 377.
Hirsch, J., et alColumbia fMRI
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Injection of radioactive-labeled water for PET scanning
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET
a. Source of signalb. Measurement techniquesc. Computation for analysis
From: Images of Mind by Posner, M. and Raichle, M. Scientific American Library, 1994, p. 24
Fixation
Flashing Checkerboard
Stimulation Fixation Difference
Individual difference images
Mean difference image
Analysis of PET Results
Hirsch, J., et alColumbia fMRI
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B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG6. Electroencephalography, EEG
MEG: MagnetoEncephaloGraphyEEG: ElectroEncephaloGraphy
Measurement of Electromagnetic Activity
Provides Information of temporal interactions
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG
a. Source of signal
Page 16
Relationship between currents in the brain and the magnetic field outside the head.
Based on the discoverythat electrical currents generate magnetic fields: Hans Christian Oersted, a Danish physicist (early 19th. century)
A current source with strength Q causes a current flow Jv within the brain.
The current flow produces a potential difference V on the scalp: (measured by EEG)
And a magnetic field B outside of the head: (measured by MEG)
from: www.Aston.ac.uk/psychology/meg/meg/intro/magfield.htm
B
JvQ
V
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG
a. Source of signalb. Measurement techniques
Magnetoencephalography, MEG
Tiny magnetic fields produced by brain activity (10-13 Teslas) can be measured using Superconducting Quantum Interference Devices (SQUIDs).
SQUIDS operate at superconducting temperatures (-269oC). Sensors are placed in a dewar containing liquid helium.
Stimulus – evoked neuromagnetic signals
are recorded by an array of detectors.
The spatial location of the source is inferred by mathematical modeling of the magnetic field pattern.
Hirsch, J., et alColumbia fMRI
Page 17
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG
a. Source of signalb. Measurement techniquesc. Computation for analysis
Somatosensory evoked magnetic signals in response to tactile stimulation of the
contralateral index finger
Isofield contour maps at the time of maximal
response (50 msec) to the tactile stimulation
Neuro magnetic response occurs about 50 msec after
the stimulation.
The field pattern is dipolar with clearly defined regions of entering (solid lines) and
emerging (dashed lines) magnetic flux.
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG6. Electroencephalography, EEG
a. Source of signalb. Measurement techniques
Page 18
Electroencephalography
Hirsch, J., et alColumbia fMRI
B. Brain Mapping Techniques
Hirsch, J., et alColumbia fMRI
1. Functional Magnetic Resonance Imaging, fMRI2. Somatasensory Evoked Potential, SSEP3. Direct Cortical Stimulation4. Positron Emission Tomography, PET5. Magnetoencephalography, MEG6. Electroencephalography, EEG
a. Source of signalb. Measurement techniquesc. Computation for analysis
Averaged Activity profiles during bilateral finger movement
Electrode Array for EEG
Electroencephalography
Hirsch, J., et alColumbia fMRI
Page 19
Hirsch, J., et alColumbia fMRI
1. Task of specificity and conjunctions
C. Integration of Brain Mapping Techniques
CONJUNCTION OF BOLD RESPONSES DURING OBJECT NAMING TASKS
VISUAL AUDITORY TACTILE
COMMONAREAS
R. Inferior Frontal GBA (45)
L. Cingulate GBA (24)
L. Inferior Frontal GBA (44)
L. Medial Frontal GBA (6)
L. Middle Frontal G BA (6)
L. Inferior Frontal GBA (45)
R
Hirsch, R-Moreno, Kim, Interconnected large-scale systems for three fundamental cognitive tasks revealed by functional MRI. Journal of Cognitive Neuroscience, 13(3), 389-405, 2001.
Hirsch, J., et alColumbia fMRI
Hirsch, J., et alColumbia fMRI
1. Task of specificity and conjunctions2. Labels of functional areas
C. Integration of Brain Mapping Techniques
a. Atlas-Based
Page 20
Hirsch, J., et alColumbia fMRI
Hirsch, J., et alColumbia fMRI
1. Task of specificity and conjunctions2. Labels of functional areas
C. Integration of Brain Mapping Techniques
a. Atlas-Basedb. Registration methods
Labeling of Active Brain AreasFunctional Brain Atlas Brain
transferactivity labels
GPrC 4GFs 6GFd 6GFs 6GRC 4LPs 7
c,Eb,Ea,E,60,-ab,E,60c,E,60b,G,60
Name BA Sector
Hirsch, J., et alColumbia fMRI
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Hirsch, J., et alColumbia fMRI
1. Task of specificity and conjunctions2. Labels of functional areas3. Connectivity computations
C. Integration of Brain Mapping Techniques
Hirsch, R-Moreno, Kim, Interconnected large-scale systems for three fundamental cognitive tasks revealed by functional MRI. Journal of Cognitive Neuroscience, 13(3), 389-405, 2001.
Map of Human Language System
Medial Frontal Gyrus Superior Temporal GyrusInferior Frontal GyrusInferior Frontal Gyrus
6224445
9574940
-6-261025
539
258
Anatomical Region BA zyx
Center of mass
Hirsch, J., et alColumbia fMRI
Hirsch, J., et alColumbia fMRI
QuickTime™ and a Video decompressor are needed to see this picture.
Page 22
Hirsch, J., et alColumbia fMRI
1. Task of specificity and conjunctions2. Labels of functional areas3. Connectivity computation4. Models of long-range connectivity
C. Integration of Brain Mapping Techniques
Lateral Pain System
Medial Pain System
M1
MedialThalamus
LateralThalamus
Hypothalamus
AMYGPB
PAG
Brain Areas Modified by Treatment of Pain
‘After-Sensation’ Related Areas Based on Vogt and Sikes, 2000
M
CG
PF
Hirsch, J., et alColumbia fMRI
Cognitive Events are caused by Neural EventsThe Astonishing Hypothesis
Hirsch, J., et alColumbia fMRI
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MissionTo establish a collaborative and multi-investigator
neuroimaging research environment focused on education, medical applications, and the study of
brain, behavior, and therapy-induced cortical effects aimed at the systems of the brain that underlie
cognition, perception, and action.
Columbia fMRI
Functional MRI Research CenterDepartment of Radiology
Center for Neurobiology and BehaviorColumbia University
College of Physicians and Surgeons
Hirsch, J., et alColumbia fMRI
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