10

From some sources, I've read that excitatory postsynaptic potentials (EPSPs) decay over time, which would imply that they aren't abolished by action potentials. However, other sources seem to indicate the opposite (although I may be misunderstanding them). Plus, the classical leaky-integrate-and-fire neuron model implies that EPSPs are abolished by action potentials (although this could well be a simplification). Does the refractory period of an action potential affect its originating EPSP? Or is it a separate phenomenon?

Christian Hummeluhr
  • 6,972
  • 4
  • 49
  • 117
visual-kinetic
  • 475
  • 2
  • 9
  • 1
    This would probably be better suited for Bio.SE. – Josh May 13 '15 at 15:05
  • 1
    I'm okay with it, basic neuroscience seems within scope for us. – Christian Hummeluhr May 13 '15 at 15:30
  • Could you add some references to,e.g., 'other sources'? Additionally, do you include action potentials in your definition of EPSPs or not? – AliceD May 14 '15 at 01:51
  • @ChristianHummeluhr - given your answer http://meta.cogsci.stackexchange.com/questions/966/neurobiology-rivalries-part-v-a-newer-hope I would tend to say that this question crosses the CogSci boundaries and I agree with Josh. This question can be grouped entirely under Biophysics which is, and probably should be non-existent here at CogSci. I am happy to answer, though, and happy to accept its inclusion here at CogSci. In that case I will create a Biophysics tag and add an answer to the Meta question regarding the outcome of this discussion. – AliceD May 14 '15 at 01:57
  • @Josh - I think this question could be a nice boundary-defining question regarding Neurobiology questions? http://meta.cogsci.stackexchange.com/questions/966/neurobiology-rivalries-part-v-a-newer-hope – AliceD May 14 '15 at 01:59
  • 2
    @AliceD My reasoning is that "basic" neuroscience falls within a cognitive science, much like neural network questions do (i.e., anyone would learn about action potentials and EPSPs during their undergrad and could answer it with a bit of reading, unlike more involved bio/neuro questions). If you think this is actually an involved biophysical question, I may reconsider. We do not need a biophysics tag. – Christian Hummeluhr May 14 '15 at 06:12
  • 1
    @ChristianHummeluhr - If basic neuroscience is CogSci, then this question should stay. – AliceD May 14 '15 at 06:32
  • 1
    @AliceD Great! I also agree with Josh that this is a good boundary question, and would upvote a Meta answer to that effect. – Christian Hummeluhr May 14 '15 at 07:57
  • you all spend way too much effort policing what is and is not acceptable questions – honi May 15 '15 at 05:58
  • @Josh I agree with Christian, basic neuroscience question are very much on-topic here. – Artem Kaznatcheev May 15 '15 at 22:42

1 Answers1

5

While model neurons like the leaky integrate and fire may use a simplification in which the neuron forgets all previous information when it emits a spike, in a biological neuron, the synapse and the soma are relatively electrically isolated from each other, so the voltage activity of the action potential does not make the synapse "forget" the EPSP. Although see back propagating action potentials for a mechanism for somatic action potentials to affect dendritic processing. (http://www.ncbi.nlm.nih.gov/pubmed/8107777)

honi
  • 1,875
  • 13
  • 33