Functional Brain Signal Processing: EEG & fMRI Lesson 9

M.Tech. (CS), Semester III, Course B50 Functional Brain Signal Processing: EEG & fMRILesson 9 Kaushik Majumdar Indian Statistical Institute Bangalore Center kmajumdar@isibang.ac.in

Buzsaki et al., Nat. Rev. Neurosci., 13: 407 – 420, 2012 Bentivogilo et al., Epileptic Disorders, 5: S27 – S34, 2003 Action Potential, LFP, ECoG, EEG

Buzsaki et al., Nat. Rev. Neurosci., 13: 407 – 420, 2012 Action Potential, LFP, ECoG, EEG (cont.) or ECoG

Buzsaki, Nat. Neurosci., 7(5): 446 – 451, 2004 LFP Acquisition

http://www.ece.unm.edu/~vcalhoun/courses/fMRI_Spring07/Lecture02_IntroTofMRI.pdfhttp://www.ece.unm.edu/~vcalhoun/courses/fMRI_Spring07/Lecture02_IntroTofMRI.pdf Hemodynamic Response

http://www.ece.unm.edu/~vcalhoun/courses/fMRI_Spring07/Lecture02_IntroTofMRI.pdfhttp://www.ece.unm.edu/~vcalhoun/courses/fMRI_Spring07/Lecture02_IntroTofMRI.pdf MRI Machine

Logothetis & Wandell, Annu. Rev. Physiol., 66: 735 – 769, 2004 BOLD vs. LFP

http://www.ece.unm.edu/~vcalhoun/courses/fMRI_Spring07/Lecture02_IntroTofMRI.pdfhttp://www.ece.unm.edu/~vcalhoun/courses/fMRI_Spring07/Lecture02_IntroTofMRI.pdf Blood Oxygen Level Dependent Signal HbO2 is dimagnetic. Deoxy-Hb is paramagnetic.

Anatomical MRI

Kandel et al., Principles of Neural Science, 4e, 2000 Elements of MRI Physics

Pooley, 2005 Larmor Equation Gyromagnetic ratio is nucleus dependent. For hydrogen it is 42.6 MHz/T.

Pooley, 2005 Radio Frequency (RF) Pulse T1 relaxation time

Pooley, 2005 Tissue Contrast Maximization by T1 Relaxation

Kandel et al., Principles of Neural Science, 4e, 2000 Relaxation Process and T2 Relaxation

Kandel et al., Principles of Neural Science, 4e, 2000 T1 and T2 Weighting

Kandel et al., Principles of Neural Science, 4e, 2000 T1, T2 Time Constants in ms at 1 Tesla for Different Tissues

Noll, 2001 One Dimensional Frequency Encoding B(x) = B0 + G.x ƒ(x) = γ(B0 + G.x)

Kandel et al., Principles of Neural Science, 4e, 2000 Slice Location

Kandel et al., Principles of Neural Science, 4e, 2000 Slice Location (cont.)

Buxton, 2009 T1 and T2 Relaxation Time

Kandel et al., Principles of Neural Science, 4e, 2000 Functional Magnetic Resonance Imaging or T2* Relaxation Imaging

Pooley, 2005 T2 and T2* Dephasing

References • G. Buzsaki, C. A. Anastassiou and C. Koch, The origin of extracellular fields and currents – EEG, ECoG, LFP and spikes, Nat. Rev. Neurosci., 13: 407 – 420, 2012. • E. R. Kandel, J. H. Schwartz and T. M. Jessel, Principles of Neural Science, 4e, McGraw Hill, New York, 2000, p. 370 – 374. • R. A. Pooley, Fundamental physics of MR imaging, RadioGraphics, 25(4): 1087 – 1099, 2005.

References (cont.) • D. C. Noll, A primer on MRI and functional MRI, available online at http://www.cs.ucsb.edu/~mturk/imaging/Misc/MRI%20primer.pdf • R. B. Buxton, Introduction to Functional Magnetic Resonance Imaging, 2e, Cambridge University Press, Cambridge, UK, 2009.

THANK YOUThis lecture is available at http://www.isibang.ac.in/~kaushik

Functional Brain Signal Processing: EEG & fMRI Lesson 9