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LAB 8 - Synaptic Function

 

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The purpose of this lab was to use a computer program to demonstrate the basic physiological properties of a neuron-neuron synapse.

Procedure

  1. Temporal summation - this exercise demonstrates how simulation of a single presynaptic cell generates EPSPs that summate over time.

All variables were reset, cell A was set to fire, the pulses was set to four, and the firing rat of A was increases from 1 to 9. Then the experiment was ran. This demonstrated temporal summation as show in the screen capture below.

  1. Effects of Changing the Time or Length Constant of Cell C - the values of tau(time constant) and lambda (space constant) influence the degree to which EPSPs summate on the surface of the postsynaptic cell.

All variables were reset, Cell A was set to fire, the pulse was set to one and then the experiment was ran. Tau was then changed and the experiment was repeated. This screen capture shows the effects of changing tau on a single EPSP.

Changing tau increases the EPSP magnitude. The line goes from being straight to having a gradual curve in it.

  1. Spatial summation - this exercise demonstrates how stimulation of multiple presynaptic inputs can generate EPSPs that sum over distance.

Changing tau increases the EPSP magnitude. The line goes from being straight to having a gradual curve in it.

  1. Spatial summation - this exercise demonstrates how stimulation of multiple presynaptic inputs can generate EPSPs that sum over distance.

Cell A was set to fire, and the firing rate to 8. Cell B was set to fire also and the firing rate to 5. the pulse was set to 5.


ZOOLOGY 310 GUIDE TO SYNAPTIC FUNCTIONS