Coherence Patterns Across the Human Cortex

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Coherence Patterns Across the Human Cortex
Vernon L. Towle, Ph.D.

• Neurology, Surgery and Pediatrics
• The University of Chicago

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The Ultimate Modeling Challenge!
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Early Functional Imaging
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The First Functional Mapper
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First Scientific Functional Mapper
Paul Broca, 1861
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Brodmann, 1909
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Macaque Cortical Connections79 areas834
pathways
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Electrophysiologic Techniques

• Direct Cortical Stimulation
• Fritz Hitzig (1870) ?
  Penfield Boldrey (1937)
• Somatosensory Evoked Potential
• Woolsey et. al. (1949) ?
  Jasper et al. (1960)
• Electrocorticography
• Jasper Fortuyn (1947) ? Goldring
  Gregorie (1984)

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Direct Electrical Stimulation
Penfield Boldry, 1954
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Expressive Speech
Penfield Boldry, 1954
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Cortical Stimulation Expressive Speech
Ojemann et al. 1989
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SubduralGrids
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Subdural Grid
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Signal-AcquisitionSystem
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Invasive Functional Mapping
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Surgical Mapping
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ECoG Coherence Patterns

• I. Scientific Questions
• Functional Localization
• Emergence of Cognition
• II. Clinical Problems
• Tumor margins
• Origin of seizures

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Evolution of Electrocorticography
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Locate the Electrodes
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Inter-ictal
Onset
Ictal
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Anatomy of a Seizure
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Coherence and Seizures

• Gotman, 1987
• Duckrow Spencer, 1992
• Zaveri et al. 1993, 2000
• Franaszczuk et al. 1994
• Bullock et al. 1995
• Bartolomei, 1999, 2000
• Le Van Quyen et al.
• 1998, 2000

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Histograms of Coherence Magnitude
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Coherence and Distance
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Two Replications
Coh
Phase
180
-180
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Epilepsy Partialis Continua
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Frontal Lobe Seizure
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Hemimegencephaly

• 8 year old male
• parietal/occipital
• cortex
• Developmental
• delay
• Daily seizures

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Coronal viere

• Post-op
• 3 sz immediately
• 0 sz at 6 months
• Ambulatory running
• Increased vocabulary

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L temporal lobe

• L frontal lobe

L frontal lobe
L parietal lobe
L occipital lobe
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Left Occipital Grid
frontal lobe
T
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Interictal Power
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Seizure Onset
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Ictal Power
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Resection and Topectomy
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Ictal Coherence
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Interictal Coherence
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Ictal Power
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Can we predict where seizures will arise?
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Interictal Ictal
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The Binding Problem
?
?
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Fast EEG oscillations information processing
Walter Freeman - 1960s
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BarthEvent-related Oscillations
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Oscillations Accompany Behavior
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Temporal Binding Hypothesis
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RolfsemaModel Building
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Task-related Beta Activity
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Task-specific Beta Band Coherence
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The Dynamic Core Hypothesis
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CoherenceChanges with Perception
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Lateral Coherence Patterns

• reflect human gyral anatomy
• are dramatically altered by pathological
  processes
• are mildly altered by cognitive/behavioral
  manipulations

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Kurt Hecox, M.D. John Hunter, Ph.D. Jean-Paul
Spire, M.D. Liela Khorasani, M.D. Michael
Kohrman, M.D. John Milton, M.D., Ph.D. Sozari
Chkhenkeli, M.D., Ph.D. Gioconda Mojika, MSI
Arnetta Gray, R.EEG.T. Diane Suarez,
R.EEG.T. Maria Chico, R.N. Diana Hanan,
B.A. Samir Shaikh Bryan Singer Katie Chiu
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Lateral Coherence
b
a
a
a
b
b
Coherence (0.0-1.0) Phase (0-180 deg)

• intracortical resonance
• subcortical driving