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Mathematical foundations of neuroscience

01 Jan 2010-Vol. 35
TL;DR: The Hodgkin-Huxley Equations are applied to the model of Neuronal Networks to describe the “spatially distributed” networks.
Abstract: The Hodgkin-Huxley Equations.- Dendrites.- Dynamics.- The Variety of Channels.- Bursting Oscillations.- Propagating Action Potentials.- Synaptic Channels.- Neural Oscillators: Weak Coupling.- Neuronal Networks: Fast/Slow Analysis.- Noise.- Firing Rate Models.- Spatially Distributed Networks.

Content maybe subject to copyright    Report

G. Bard Ermentrout • David
H.
Terman
Mathematical Foundations
of Neuroscience
43 Springer

Contents
1
The Hodgkin—Huxley Equations
.................................................................
1
1.1
The Resting Potential
...................................................................
1
1.2
The Nernst Equation
.....................................................................
3
1.3
The Goldman—Hodgkin—Katz Equation
.........................................
5
1.4
Equivalent Circuits: The Electrical Analogue
................................
8
1.5
The Membrane Time Constant
.....................................................
11
1.6
The Cable Equation
......................................................................
13
1.7
The Squid Action Potential
...........................................................
16
1.8
Voltage-Gated Channels
...............................................................
18
1.9
Hodgkin—Huxley Model
...............................................................
20
1.10
The Action Potential Revisited
.....................................................
25
1.11
Bibliography
.................................................................................
27
1.12
Exercises
......................................................................................
28
2
Dendrites
........................................................................................................
29
2.1
Multiple Compartments
................................................................
29
2.2
The Cable Equation
......................................................................
33
2.3
The Infinite Cable
.........................................................................
34
2.4
Finite and Semi-infinite Cables
.....................................................
36
2.5
Branching and Equivalent Cylinders
.............................................
38
2.6
An Isolated Junction
.....................................................................
40
2.7
Dendrites with Active Processes
....................................................
42
2.8
Concluding Remarks
.....................................................................
45
2.9
Bibliography
.................................................................................
45
2.10
Exercises
.......................................................................................
45
3
Dynamics
........................................................................................................
49
3.1
Introduction to Dynamical Systems
...............................................
49
3.2
The Morris—Lecar Model
..............................................................
49
3.3
The Phase Plane
............................................................................
51
3.3.1
Stability of Fixed Points
...................................................
52
3.3.2
Excitable Systems
...........................................................
53
3.3.3
Oscillations
.....................................................................
55
ix

x
3.4
3.5
Contents
Bifurcation Analysis
......................................................................
56
3.4.1
The Hopf Bifurcation
........................................................
56
3.4.2
Saddle—Node an a Limit Cycle
........................................
58
3.4.3
Saddle—Homoclinic Bifurcation
.......................................
60
3.4.4
Class
I
and Class II
..........................................................
62
Bifurcation Analysis of the Hodgkin—Huxley Equations
.................
63
3.6
Reduction of the Hodgkin—Huxley Model to a Two-Variable Model 66
3.7
FitzHugh—Nagumo Equations
........................................................
69
3.8
Bibliography
..................................................................................
70
3.9
Exercises
.......................................................................................
70
4
The Variety of Channels
........................................................................
77
4.1
Overview
.......................................................................................
77
4.2
Sodium Channels
...........................................................................
78
4.3
Calcium Channels
..........................................................................
80
4.4
Voltage-Gated Potassium Channels
...............................................
82
4.4.1
A-Current
........................................................................
83
4.4.2
M-Current
........................................................................
85
4.4.3
The Inward Rectifier
.........................................................
86
4.5
Sag
................................................................................................
87
4.6
Currents and lonic Concentrations
.................................................
88
4.7
Calcium-Dependent Channels
........................................................
90
4.7.1
Calcium Dependent Potassium:
The Afterhyperpolarization
..............................................
90
4.7.2
Calcium-Activated Nonspecific Cation Current
.................
93
4.8
Bibliography
..................................................................................
95
4.9
Exercises
.......................................................................................
95
4.10
Projects
.........................................................................................
100
5
Bursting Oscillations
..............................................................................
103
5.1
Introduction to Bursting
.................................................................
103
5.2
Square-Wave Bursters
....................................................................
105
5.3
Elliptic Bursting
............................................................................
111
5.4 Parabolic
Bursting
..........................................................................
114
5.5
Classification of Bursters
...............................................................
117
5.6 Chaotic Dynamics
.........................................................................
118
5.6.1
Chaos in Square-Wave Bursting Models
..........................
118
5.6.2
Symbolic Dynamics
.........................................................
121
5.6.3
Bistability and the Blue-Sky Catastrophe
.........................
123
5.7
Bibliography
125
5.8
Exercises
.......................................................................................
126

Contents
6
Propagating Action Potentials
.....................................................
xi
129
6.1
Traveling Waves and Homoclinic Orbits
................................
130
6.2
Scalar Bistable Equations
........................................................
132
6.2.1
Numerical Shooting
..................................................
135
6.3
Singular Construction of Waves
..............................................
136
6.3.1 Wave Trains
................................................................
139
6.4
Dispersion Relations ................................................................
139
6.4.1
Dispersion Kinematics ..............................................
141
6.5
Morris—Lecar Revisited and Shilnikov Dynamics
.................
141
6.5.1
Class II Dynamics ......................................................
142
6.5.2
Class
I
Dynamics
.......................................................
143
6.6 Stability of the Wave
................................................................
145
6.6.1
Linearization
..............................................................
146
6.6.2
The Evans Function
...................................................
147
6.7
Myelinated Axons and Discrete Diffusion
.............................
149
6.8
Bibliography
..............................................................................
151
6.9
Exercises
....................................................................................
152
7
Synaptic Channels
.......................................................................
157
7.1
Synaptic Dynamics
...................................................................
158
7.1.1
Glutamate
...................................................................
161
7.1.2 y-Aminobutyric Acid
.................................................
162
7.1.3
Gap or Electrical Junctions
........................................
164
7.2
Short-Term Plasticity
................................................................
164
7.2.1
Other Models
.............................................................
167
7.3
Long-Term Plasticity
................................................................
168
7.4
Bibliography
..............................................................................
169
7.5
Exercises
....................................................................................
169
8
Neural Oscillators: Weak Coupling
...........................................
171
8.1
Neural Oscillators, Phase, and Isochrons ...............................
172
8.1.1
Phase Resetting and Adjoints
....................................
174
8.1.2
The Adjoint .................................................................
177
8.1.3
Examples of Adjoints
..................................................
178
8.1.4 Bifurcations and Adjoints
..........................................
181
8.1.5
Spike-Time Response Curves
....................................
186
8.2
Who Cares About Adjoints?
.....................................................
187
8.2.1
Relationship of the Adjoint and the Response
to Inputs
.......................................................................
187
8.2.2
Forced Oscillators
......................................................
189
8.2.3
Coupled Oscillators
.....................................................
193
8.2.4
Other Map Models
......................................................
199
8.3
Weak Coupling
..........................................................................
202
8.3.1
Geometrie Idea
.............................................................
203
8.3.2
Applications of Weak Coupling
.................................
205

xii
8.3.3
Synaptic Coupling near Bifurcations
......................
8.3.4
Small Central Pattern Generators
............................
8.3.5
Linear Arrays of Cells
............................................
8.3.6
Two-Dimensional Arrays
........................................
8.3.7
All-to-All Coupling
................................................
Contents
206
208
213
217
219
8.4
Pulse-Coupled Networks: Solitary Waves
............................
223
8.4.1
Integrate-and-Fire Model
........................................
226
8.4.2
Stability
.................................................................
229
8.5
Bibliography
........................................................................
229
8.6
Exercises
.............................................................................
229
8.7
Projects
...............................................................................
238
9
Neuronal Networks: Fast/Slow Analysis
.........................................
241
9.1
Introduction
.........................................................................
241
9.2
Mathematical Models for Neuronal Networks
......................
242
9.2.1
Individual Cells
......................................................
242
9.2.2
Synaptic Connections
............................................
243
9.2.3
Network Architecture
............................................
245
9.3
Examples of Firing Patterns
................................................
246
9.4
Singular Construction of the Action Potential
.....................
249
9.5
Synchrony with Excitatory Synapses
...................................
254
9.6
Postinhibitory Rebound
.......................................................
258
9.6.1
Two Mutually Coupled Cells
..................................
258
9.6.2
Clustering
..............................................................
260
9.6.3 Dynamic Clustering
..............................................
260
9.7
Antiphase Oscillations with Excitatory Synapses
................
262
9.7.1
Existence of Antiphase Oscillations
.......................
263
9.7.2
Stability of Antiphase Oscillations
........................
266
9.8
Almost-Synchronous Solutions
...........................................
269
9.8.1
Almost Synchrony with Inhibitory Synapses
.........
269
9.8.2
Almost Synchrony with Excitatory Synapses
.........
271
9.8.3
Synchrony with Inhibitory Synapses
.....................
274
9.9
Slow Inhibitory Synapses
....................................................
275
9.9.1
Fast/Slow Decomposition
......................................
275
9.9.2
Antiphase Solution
...............................................
276
9.9.3
Suppressed Solutions
.............................................
278
9.10
Propagating Waves
.............................................................
278
9.11
Bibliography
.......................................................................
282
9.12
Exercises
............................................................................
282
10
Noise
......................................................................................................
285
10.1
Stochastic Differential Equations
........................................
287
10.1.1
The Wiener Process
..............................................
288
10.1.2
Stochastic Integrals
...............................................
289
10.1.3
Change of Variables: Itö's Formula
........................
289

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