FALL 2007
NEUROPHYSIOLOGY NSC4356
Mondays and Wednesdays, 11:30-12:45PM, HH2.402
Dr. Larry Cauller,
x4592, e-mail lcauller@utdallas.edu
Office hours GR4.412
(next to elevators) on Thurs 1-2PM or by appointment
website
http://www.utdallas.edu/~lcauller
COURSE SUMMARY
This course will introduce students to the fundamental concepts of electrophysiology and the biophysics of excitable membranes necessary for a sophisticated understanding of the individual and collective behavior of interconnected neurons. These biophysical principles are the basis for our understanding of how neurons and other cells, such as sensory receptors and muscle or cardiac cells, respond to, generate and propagate bioelectrical signals. In addition, this course will examine the electrophysiology of synaptic transmission whereby the signals generated by one neuron are transmitted to generate the electrical response of the next neuron. This undergraduate course has become a core requirement for the Neuroscience degree.
COURSE STRUCTURE and PLAN
The overall structure of this course is designed to provide a solid foundation of elementary principles which are incrementally constructed into a comprehensive understanding of complex neural phenomena. We will progress carefully from the simplest concepts (e.g. what is an ion? Volts?) without resorting to convenient shortcuts or hand-waving to promote the personal confidence that can only develop when students learn how to completely explain what they’ve learned. This course emphasizes the nano-scale nature of the membrane and ions submerged in a world where water molecules drive every action. We’ll cover the basic principles of electronic circuits (e.g. Ohm's Law) to model the passive properties of neuronal structures (e.g. length and time constants) for the construction of a unified description of the spatio-temporal propagation of neuronal signals in the form of the partial differential ‘cable’ equation, and discover how the simple solutions of this complex equation can be applied throughout nature. All the factors related to the energetics generated by ionic gradients (e.g. Nernst equilibrium potentials) will be considered to fully understand what drives all neural activity. We will thoroughly examine the fundamental kinetics of voltage-dependent channel kinetics for a comprehensive understanding of the Hodgkin and Huxley equations which represent a pivotal milestone in the history of Neuroscience by providing a brilliant explanation of the action potential signals that are central to all neural behavior. Then we will examine how these active signals are transmitted through synapses to influence the behavior of other neurons. With the greater insight gained from our mastery of these essential neurophysics, we will consider the mechanisms responsible for the unique behavior of primary cortical neurons and discover how widespread neuro-modulatory inputs (e.g. cholinergic and noradrenergic) can influence the general state of the nervous system (e.g. waking and sleeping) by simply changing the most basic neuronal properties (e.g. overall conductance).
MATH is COOL (not scary)
This course must necessarily involve mathematical descriptions of the physical processes responsible for these bioelectric phenomena. Every effort will be made to provide every student with careful instruction on these mathematical tools, such that a basic proficiency with precalculus mathematics (e.g. multiplying powers of ten and using a calculator) should be sufficient for excellent performance. Indeed, a central theme of this course is that the mathematics describing even the most complex neuro-physics are surprisingly simple. Unlike this course, most mathematics courses students have taken (often resulting in the general inferiority complex afflicting most neuroscientists when it comes to math) are designed to extend one’s technical skills to address a greater range of general applications. In contrast, this course is designed to show how mathematics focused upon specific neural phenomena help to de-mystify the complexity, reinforce the confidence that every factor has been considered for a complete understanding. Math is really great if you can overcome your fear.
TEXTS and RESOURCES
Students will be provided with extensive worksheets available by free download that explicitly present the concepts and methods that will be taught in class, including numerous example problems and solutions. Lectures will refer to material in the same texts required for the Behavioral, Cellular, Developmental and Integrative Neuroscience core courses. For instance, many of the figures presented in class correspond to those in either Kandel’s Principles of Neural Science or Purves’ Neuroscience texts used for the Cellular, Developmental and Integrative courses this semester. A host of equally helpful Neurophysiology texts may be found in many bookstores on online from Amazon (e.g. Stein’s Intro NeuroPhys from $1.64, or Atwood’s Essentials of Neurophys from $4.59 – I’ve not reviewed either of these). Students are encouraged to also get the supplementary text: Neurons in Action by John Moore, which uses computer simulations to illustrate many of the processes covered in this course (or download Neuron for free from www.neuron.yale.edu). This course is complemented by the Neurobiology Laboratory Methods course (NSC4353) but requires no prerequisites such that students from all disciplines are encouraged to participate (contact Dr. Cauller for special permission if necessary).
GRADING
Grading will be based upon class participation (up to 5% extra), two Take Home Exams (25% each) and a comprehensive Final Exam covering material presented over the full course of the semester. A quiz, consisting of a few problems equivalent to those found on the worksheets, will be given each week, usually at the beginning of the Wednesday class. The quizzes will not be graded but will be used to track individual student progress, identify teaching effectiveness and gauge the pace of the course. The Take Home Exams are intended primarily as a teaching tool and will only be used to raise the final score (e.g. course grade will be the highest possible weighted mean of Take Home Exams and Final Exam weighted 25%, 25%, 50%, respectively if both Take Home Exams were greater than Final Exam, or 25%, 75% if only one Take Home Exam was greater, or 100% Final Exam if best). While students may refer to any outside sources to complete these Take Home Exams, students are expected to maintain the highest ethical standards of personal Honor and work independently on these Take Home Exams, limiting any interactions with anyone else that might be relevant to the Exam to the most general terms (e.g. which worksheet covers this material? Or when must we hand in our test?), without any reference to specific solutions. Check with instructors (e-mail preferred) for permission to contact others about questions that may violate the Honor Code, mostly because we are the most likely to know the correct answers. Take Home Exams will be distributed on a Monday class and collected at the beginning of the next Monday class when the Take Home Exam will be meticulously reviewed with solutions presented in class. Therefore, no Exams may be accepted after the beginning of this Review Class. All problems on the Final Exam will be equivalent to questions included in the two Take Home Exams. During the Final Exam, students will receive copies of both Worksheets for general reference (i.e. memorization isn’t as important as knowing what to do).
CLASS SCHEDULE:
Week 1: Introduction and Elementary Principles
Aug 20, 22
Week 2: Water and Ions and Membranes
Elementary Electricity (Ohm's Law)
Aug 27, 29
Week 3: Electronic Circuit Elements and
Membrane Properties
LABOR DAY off Sep 3, Sep 5 Class on
Week 4: Passive Signal Propagation (Cable Equation)
Ionic Gradients (Nernst Potentials)
Resting Potentials (Conductance-weighted mean Voltage)
Sep 10, 12
Week 5: The Action Potential (Hodgkin and Huxely)
Sep 17, 19
Week 6: Active Conductances (Voltage-Sensitive Channels)
Sep 24, 26
Week 7: Sodium and Potassium and Calcium
Channel Kinetics
TAKE HOME
EXAM 1
Oct 1, 3
Week 8: REVIEW
TAKE HOME EXAM 1
Oct 8, 10
Week 9:
Oct 15, 17
Week 10: Synaptic Potentials
Oct 22, 24
Week 11: Extracellular Neural Signals:
Spike Activity and Field Potentials
Current Source Density
TAKE HOME EXAM 2
Oct 29, 31
Week 12: REVIEW TAKE HOME EXAM 2
Nov 5, 7
Week 13: Analysis of extracellular neural signals:
Noise and Signal Averaging
Peri-Stimulus Time Histograms
Auto- and Cross-Correlations
Nov 12, 13
Week 14: Computational Neurophysiology:
Computer simulation of neural activity
Nov 19, 21
Week 15: General Review and Wrap-up
Nov 26 THANKSGIVING DAY off, Nov 28 Class on
FINALS WEEK
Dec 3 - To be arranged.