The reason of neuron to be at threshold

Related BrainMass Solutions

• What happens when the membrane potential reaches threshold?

  Heightened membrane potential causes the opening of sodium channels, but this allows sodium to flow INTO the cell This solution helps explain what happens when the membrane potential of a neuron reaches threshold.

• Factors Affecting Action Potentials

  That means, they must be added together at the same time. If, after we add all of the signals together, we reach threshold, then an action potential will fire.

• Turing Machines and PDP Networks

  The threshold value θ is a fixed threshold value unique to the neuron, and the model is assumed to be operating in discrete time steps.

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  Since the salty cytoplasm of an axon is electrically stimulated and the myelin inhibits charge leakage through the membrane, depolarization at one node of Ranvier is enough to raise the voltage at a nearby node to the threshold for action potential initiation

• Discussion on action potentials

  The whole process can be simplified to four main parts: 1) Resting potential- when the neuron is not stimulated, it is said to be at resting potential. Inside the neuron is negative when compared to the outside.

• Determining Neuronal Activity

  106345 Determining Neuronal Activity Since at any moment a neuron is likely to have thousands of neurons releasing neurotransmitters at its surface, how is neuronal activity (to fire or not to fire) determined?

• EPSP/IPSP

  The sum effect of all of these excitatory and inhibitory input signals determines the effect on the postsynaptic neuron. If the sum of excitatory signals is greater than the inhibitory signals, then an EPSP is generated.

• Neuron Transmission

  This causes the inside of the cell to become more positive, and hence the effect is depolarizing. If enough of this occurs, the membrane potential will reach threshold and trigger an action potential.

• Action Potential and Ion Regulation

  However, a neuron does not commit to depolarization until the threshold potential is reached at -55 millivolts. 2) Once -55 millivolts is reached, a rapid deplolarization to 30 millivolts then occurs.