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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

How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
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.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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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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