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63 lines
1.8 KiB
Typst
63 lines
1.8 KiB
Typst
// Main VL Template
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#import "../preamble.typ": *
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#show: conf.with(
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// May add more flags here in the future
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num: 3
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)
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= Synapses
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The synapses are the connection between two neurons.
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The transportation of the signal goes in three stages $"chemical" -> "electrical" -> "chemical"$.
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Chemical synapses are very common for learning.
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There are different neurotransmitters.
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Where as GABA is the most present inhibitory transmitter (it makes the AP more negative).
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Glutamate is the most relevant exititory transmitter.
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Glycine is also inhibitory.
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NMDA is a chemical agonist. It opens just certain channels.
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The presynaptic signal does depolarize the other cell to be positive.
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The reversal potiential does start when you open all the channels it is usually plus 30.
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Q: What is LTP?
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Synapses are used to trasmit signals from the axon of a source to the dendrite of a target neuron.
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There are electrical and chemical synases.
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At an electrical synapse we have direct electrial coupling
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At a chemical synapse a chemical subastanse is used to trasport the signal.
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Electrical synapses operate bi -directional and are extremely fast.
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AP creates a negative calcium current which are opeing the cages for the transmitters.
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EPSP and IPSP
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General reduction of the Hodgkin-Huxley Model
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2 dimensioanl Neuron Models
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$
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tau (dif u) / (dif t) = F (u,w) + I (t) \
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tau_(w) (dif w) / (dif t) = G (u,w)
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$
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where $I (t)$ is a Stimulus.
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This leads to the following equations where $beta and gamma$ are constants.
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$ (dif u) / (dif t) = u - (u^3 ) / (3) - w + I \
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(dif w) / (dif t) = epsilon (u + beta - gamma w) \
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$
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An introductionary example is the harmonix Oscillator (already did this in physics class).
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The crossing of the nullclines show the fixpoints.
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Van der Pol differential equations.
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