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5.) Give parameters that are used and explain parameters that are dependent on simulations.

6.) Run simulations by going through the matlab prompt and display results.

Cell models

Below is a quick description of the basic dynamics of neurons and how messages are relayed in neuronal networks. The mathematical model that is used in the simulations is given in detail.

The basic function of a neuron is the ability to relay information by means of an action potential. This is a quick depolarization burst which originates at the cell soma (main body) and travels down the axon reaching boutons. At a bouton the depolarization will cause neurotransmitters to be released into the synaptic cleft, a small space between the bouton and a spine of the target cell. The neurotransmitter then opens ion channels in the postsynaptic receptor area that can serve to excite or depress the post-synaptic neuron, depending on whether the sending neuron is excitatory or inhibitory. A cell achieves an action potential when it receive enough excitation from other cells. When the cell voltage reaches a certain threshold its firing mechanisms kick in and generate an action potential. The firing mechanism consists of voltage gated ion channels in the cell's soma membrane. These channels permability are dependent on voltage levels and are specialized to only allow specific ions to pass through. The standard action potential starts with stimuli which raises voltage sufficiently to open N a + channels. Then N a + floods in (due to diffusion) causing a depolarization of the cell. When the voltage reaches the near peak depolarization K + gating channels open allowing K + to rush out, lowering the potential back to rest. There are additional ions which have a role in cell dynamics. One important ion that helps regulate firing rates is C a 2 + . C a 2 + levels are important because they open C a 2 + dependent K + channels. More K + channels lead to greater repolarization, increasing refractory times between firing and leading to lower activity. We will look at two different sources of C a 2 + . One, through voltage gated channels. The second from NMDA receptor channels, which will be discussed in further detail ahead.

Cell types

There are two basic types of cells: excitatory and inhibitory. When excitatory cells fire they increase the potential in the neurons they synapse onto. Whereas, inhibitory decrease the potential. For our purposes we will use different parameters to the two cells different characteristics.

Mathematical model

The excitatory cell model used has 4 compartments per cell. The first compartment represents the soma. The other three are a chain of dendrites, which represent a collapsed dendritic tree at different distances from the soma. In the case of an inhibitory cell there will only be 2 total compartments. Cells will synapse onto compartment 4 if it is a E (excitatory) to E connection. Compartment 1 if it is an I (inhibitory) to E connection. Compartment 2 if it is an E to I connection.

Below is the main differential equation that governs the cell voltage in a compartment. The first term in the fraction represents the leak current. The second term is the summation of current that comes in from neighboring compartments. The third term represents Ion channel currents; they are only present at the cell soma. The fourth term is current entering from synaptic input.

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, The art of the pfug. OpenStax CNX. Jun 05, 2013 Download for free at http://cnx.org/content/col10523/1.34
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