Talk:Excitatory postsynaptic potential

Acetylcholine

I updated a statement that said, to paraphrase, "acetylcholine is the major excitatory neurotransmitter in the invertebrate nervous system". While acetylcholine does play an important part in many invertebrate nervous systems, so does glutamate. I edited the statement to be more flexible.

—―

^{Niubrad (talk) 22:20, 20 November 2014 (UTC)}

Untitled

Should the figures be EPSP rather than PPSP?

PPSP is probably French; changed it to EPSP.

Sources

No references listed. Please update. --1000Faces 17:38, 6 September 2007 (UTC)

sodium anions should read sodium cations in the section on fEPSPs —Preceding unsigned comment added by 155.58.11.16 (talk) 13:43, 2 October 2007 (UTC)

Gah! Fixed, thanks for catching this. delldot talk 14:03, 26 July 2008 (UTC)

Assessing

This is a very basic concept in neuroscience, so the lead ought to start by explaining it in simple functional terms, e.g., an EPSP is a rise in membrane potential produced by a synapse, which increases the probability that the postsynaptic cell will fire an action potential in the near future. That is, something that a reader with only a rudimentary understanding of synapses and neuro-electricity can make sense of. Looie496 (talk) 17:23, 20 September 2008 (UTC)

except that an EPSP is actually a decrease of the membrane potential...--Millencolin (talk) 21:59, 21 January 2009 (UTC)

It's true that it's a decrease in potential, that is: the difference in charges over the membrane but it is also an increase in the voltage since, viewing it from the inside of the cell, the potential goes from a negative value (eg -70mV) to a less negative value (eg -10) to a positive value (if threshold is reached). —Preceding unsigned comment added by Tamte (talk • contribs) 11:22, 9 January 2010 (UTC)

It could be mentioned that the definition presented here "A PSP is excitatory if it makes the neuron more likely to fire an action potential" doesn't just mean the synapse has a depolarizing effect. The reversal potential of the ion channels involved must be above the action potential threshold also. This requires also mentioning reversal potentials, which are not mentioned in this article. It's probably important to point out that a neurotransmitter by itself isn't excitatory -- it's the interaction between the neurotrasmitter and its binding ion channel that is excitatory. Everybody knows this is nowhere (talk) 15:24, 4 February 2014 (UTC)

Field EPSPs

"The extracellular signal from a single neuron is extremely small and thus next to impossible to record." This is a completely misleading statement, Barnes & McNaughton, Buzsaki group (too name just a few), routinely do this with hundreds of neurons. Including dozens from individual tetrodes. —Preceding unsigned comment added by Brngk (talk • contribs) 16:53, 23 March 2010 (UTC)

Request another image

Temporal Summation of EPSPs. The trace on the left shows the EPSP generated by a single spike in the presynaptic neuron. The trace on the right shows the EPSPs generated by a burst of spikes in the presynaptic neuron. Notice how the EPSPs resulting from the burst of spikes is able to reach the threshold of eliciting an action potential in the postsynaptic neuron

Studentne (talk) 04:46, 12 April 2011 (UTC)

@Studentne: I think this is a much superior & helpful image! Very nice! Why not just add it? Does anyone have any objection to replacing the existing image with this one?

I do wonder, though, if the probe in the presynaptic neuron shouldn't be in the axon terminal (to show the spike/s where they are), and the probe in the postsynaptic neuron be in the axon hillock (showing the resultant potential, summations &/or consequent spike where they are)? UnderEducatedGeezer (talk) 03:15, 11 April 2016 (UTC)

In theory you are correct. In practice to do such a recording would be very difficult and practically impossible. Also the wave forms would look different in the axon hillock region due to large amount of sodium channels. Classically, most people think of the soma as the point where integration occurs even though in reality the axon hillock does the integration. As with every figure, clarity and simplicity is preferred at the expense of accuracy. — Preceding unsigned comment added by Studentne (talk • contribs) 16:00, 3 June 2016 (UTC)

alpha function

should add a description of the functional form the EPSP waveform typically takes, as described here for example. (click on the link therein titled "AlphaSynapse".) . — Preceding unsigned comment added by Bjarthur (talk • contribs) 12:22, 20 September 2017 (UTC)