Talk:Summation (neurophysiology)

Peer review

The first problem that comes to mind here is your lack of references. For example, you mention Dale's law but do not cite the source from which you learned about it. You also did not reference anything in your other sections which may lead people to distrust your statements since they lack proof. Outside of that there are some other points that you could work on. In the historical context section you did not mention the importance of studies on the squid's axon. This was a major contributor to research on nerves and synaptic terminals due to its size. Also, in your temporal summation section, you failed to bring up the notion of pre-synaptic and post-synaptic cells which makes your statements somewhat confusing. Also, the wording is confusing. A better way to state your opening line would be that this deals with two ore more action potentials arriving at the presynaptic terminal in quick succession leading to an enhanced response of the postsynaptic cell. From there you could go on and talk about electrical synapses and what this means in that respect. Lastly, in the spatial summation section you failed to mention the effect of the location of the synapse on the dendrite. The synapses closer to the action hillock have a greater effect on the postsynaptic cell since the current they create leaks out less before reaching the hillock. There could be some equation out there relating distance and strength which you could mention and really solidify this section of your stub. Lakkisi (talk) 04:34, 6 April 2011 (UTC)

Peer Review

The below review does a good job explaining some of the major things that need to be clarified in this article. I agree with the fact that the wording in some of the section especially the historical section can be at times confusing. I would also advise at lengthening the article. The rubric says to have about ten paragraphs written, and I think the article is a little short. Some ways to expand this to solve the problem might be to look at some diseases associated with summation. I am not sure of any specific examples, but I'm sure some diseases are associated with summation which could be included in the article. Also, another thing I noticed was the lack of a section dealing with current research. This section is included in the rubric and should be added to the article. Maybe you could look for research being done today or inconclusive research done recently about summation. I found research being done on summation involved in human vision, so maybe you could start there. I think beside the wording in different areas of the article, it contains a lot of good information, and with some revisions could be a good article. I hope this helps. Finnry (talk) 21:05, 6 April 2011 (UTC)

As the previous reviews have mentioned, in order to improve this article you will need to find additional references and make sure to cite the information that you present. In addition, you could also add more links to other wikipedia pages, especially in the first two sections, in order to help the reader gain an understanding of some of the biological concepts that he/she may not be familiar with. I think that the differences between temporal and spatial summation need a more in depth explanation - try to first explain the basic concepts behind the two types of summation in general terms that the average reader would be able to understand, then perhaps you could allude to some specific examples of historical studies that have clarified the mechanism behind them and specific circumstances under which each occurs. To help your explanation, you could also include an image that clarifies and compares both types of summation. Furthermore, you addressed several concepts in the lead paragraph that were not explained in more detail later on in the article. More detailed explanations of topics such as the dependence of the response on the type of channel involved, Dale's Law, and EPSP and IPSP could help expand the article. Hope these suggestions help improve your article. Kamilaosypiuk (talk) 05:01, 7 April 2011 (UTC)

Just as mentioned in the above critiques, the biggest issue to be resolved in this article is the lack of referencing. With the exception of the last subsection, there are no in-text references. These need to be added to validate the information presented in the article. I would also recommend that more in-text links be added, especially in the introduction section. While the article was well-written overall, it could use some expansion. It seemed a bit short in length, and could perhaps be lengthened by adding information concerning disorders that pertain to summation, more detailed information about the mechanism of summation itself, or adding to the subsections that only contain between 1-3 sentences. An image could also be useful in the section detailing the differences between electrical and chemical synapses. A few more specific corrections to note: In the Historical Context section, a typo is present: "nd" is written rather than "end". Additionally, the second to last sentence in this section does not seem to make sense. I would suggest rewording your thoughts here to be more clear. Hopefully these suggestions will help! Keaneybr (talk) 00:25, 8 April 2011 (UTC)

Peer Review

This article is fairly well written, however I would suggest just taking a second or third read over to get out any of the grammar/ spelling errors that you might have missed when you wrote this. This article is written in a way that gives tons of scientific information in a easily understood fashion for any potential wikipedia reader even if they do not have much background in science. However you are lacking in references, links, and overall length.

Obviously you need to add some citations for this article just to give your article some validity. There are so many places where it obvious that a citation is needed, such as the last sentence of the introduction, the Bernard Katz implementation, one for the whole presynaptic transmission paragraph, etc. It would also help if you linked more pages to your article, since there are very few links, this would help direct the reader to more information about the topic. I also think that each paragraph could be expanded and the article as a whole needs to be expanded since you only have 8 paragraphs. The area about electrical and chemical synapses could be explained more just from what we have learned from class and a picture of each type of synapse could be added as a visual aid. If you just go to the electrical and chemical synapse wikipedia page, there are a few pretty good diagrams. Then in the common neurotransmitters section you might want to expand upon each neurotransmitter describing the mechanism and function of each more and explain whether they are normally a excitatory or inhibitory neurotransmitter. Glutamate, serotonin, and GABA could be added to this list since they are also important neurotransmitters. Then with the other sections, we have learned a lot about each in class, so I don't think it would be too difficult to expand upon each just from knowledge that you already know just to get the article up to 10 paragraphs. Maybe using pubmed or google scholar you could find a review that summarizes much of what we have covered in class to cite as a reference, or you might want to ask Burdo if you can even cite your text book.Lauren.ching (talk) 02:26, 8 April 2011 (UTC)

I think you can do a lot better with this article considering that there are a lot of information about it (it may have been difficult because you have too much information and you don't know what to add). On the history section, you can add more details to describe the historic findings so that the general public can read and understand the article as well. You may want to add links referring to another article on wikipedia (such as End Plate Potential and MEPP) or if there is not already an article about it, you can expand on that topic by creating a sub-heading (I don't think MEPP article is currently present so you can possibly expand on this (figures would help). The focus of the article should be summation. As such, I think more details and focus should be given to temporal and spatial summation section. All other sections are probably mentioned in other articles but it wouldn't hurt to add more relevant information for the flow of the article. More of mechanisms and biochemistry involved in summation would be helpful. If there are any current research related to summation, you can add that at the end of the article to conclude. Finally, I think more references should be found to better support and elucidate the article. Thanks,Young B. (talk) 6:30, 7 April 2011 (UTC)

A good start, but there’s lots of room for improvement. First, as everyone else has said is the referencing issue. Take care of that. Secondly, I would recommend linking terms throughout the article to their Wikipedia pages, so as to ensure that it is easy to understand terms that are unknown. For the “Common neurotransmitters” and “Presynaptic transmission” sections, you only have lists/bullet points. You should at least add a sentence or two to introduce the terms or what your list is for. This will make it clearer and more professional looking than simply a list. Finally, in the Temporal Summation section you had a section on vision. You may want to think about making this a subsection in Temporal summation. Overall, I felt that the article was somewhat light. That could be just me, and also I don’t know how much information is out there. But maybe check again with Pubmed. Just a thought. But overall, good job and keep working. BrianJLike (talk) 03:37, 8 April 2011 (UTC)

As I am sure many people before me have stated, you need to link to more articles in the first half of your page. Just looking at it quickly I see that you can link to Dale's principle, synapses, axons, neurotransmitters, dopamine (DA), acetylcholine (Ach) and norepinephrine (NE). There are many more possible links that you can make; you just need to look for them. I also noticed several spelling mistakes (one of which is in Minature End Plate Potential… you missed the e on end). Many of your sections could use more elaboration to create a smoother flowing and more informative article. The information you used about Dale’s Law is also outdated. Dale’s principle, as it should be referred to, is a controversial topic that has two different meanings depending on the interpretation of his words. In the introduction you should either state the version of Dale’s Principle that you are referring to, or you should eliminate that from the page altogether. Good Luck with the editing. Oconnedp (talk) 05:24, 8 April 2011 (UTC)

I really enjoyed reading this article, especially since I wanted to incorporate some information on summation in my Wikipedia article (Excitatory Synapse) and saw how minimal the information was on the page before you guys edited it! The image is great, however I’m not really sure if the section on neurotransmitters is needed, but if you guys think so, maybe you should move it to the end of the article? And maybe add some more and/or expand on the ones you have listed? I just found that it was kind of thrown in the middle and broke up the flow of the article. Also, I was thinking that maybe after the historical context, you might want to begin with the Presynaptic Transmission section and then either discuss chemical vs. electrical synapses in that section, or keep it as a second section that follows the Presynaptic Transmission section. That way you can move onto the Excitatory and Inhibitory Postsynaptic Potentials part and your presentation of information will follow the transmission of the signal! This may make it easier to understand for readers who are new to neuroscience. Wilsonga (talk) 2:35, 8 April 2011 (UTC)

Problem with lead

I don't want to chip in when there is such active editing going on, but I have to point out that there is a statement in the lead that is way off the mark, namely, "According to Dale's principle, every neuron can have only one type of synapse attached to the branches of its axon; it either excites all neurons that it sends signals to, in which case it is called an excitatory neuron, or it inhibits all neurons that it sends signals to, in which case it is called an inhibitory neuron." That's a serious misstatement of Dale's principle: it says that a neuron releases the same chemical neurotransmitters at all of its synapses. It is entirely possible for those transmitters to have excitatory effects on some targets and inhibitory effects on others, depending on the receptors on the target cells. Strictly speaking there is no such thing as an excitatory neuron or an inhibitory neuron. In practice, though, neurons that release glutamate are often called excitatory, because the most important glutamate receptors have excitatory effects; neurons that release GABA or glycine are often called inhibitory, because the most important receptors for those transmitters have inhibitory effects. Neurons that release other transmitters, such as acetylcholine, serotonin, dopamine, etc, cannot properly be called either excitatory or inhibtory: they often have different effects on different targets. Looie496 (talk) 15:38, 29 April 2011 (UTC)

End of Boston College BI481 Project

Hi guys, the article has certainly been improved since you started, but some issues remain. A sampling of them are discussed below:

• You are required to address the peer review comments left on the discussion page. Either incorporate the suggestions or respond back as to why you chose not to do so.
• The first two paragraphs of your intro discuss some important points about excitatory vs. inhibitory effects, as well as temporal and spatial summation. The concepts need to be reworded to make them more accessible to a lay audience. As it stands now the writing is somewhat confusing.
• For the Interneuronal relations diagram, I like that you tried to make your own diagram, but the effect of disinhibition and disfacilitation on the final neuron needs to be indicated. Also, the diagrams for spatial and temporal summation are confusing in that they don't really show how graded potentials can be summed in a postsynaptic cell.
• In the Mechanism section, you state "Neurotransmitters bind to receptors which open or close ion channels in the postsynaptic cell creating postsynaptic potentials (PSPs)." Not all neurotransmitter receptors are ionotropic. Some metabotropic receptors are not linked to ion channels.
• Also in the Mechanism section you state "These potentials alter the chances of an action potential occurring in a postsynaptic neuron. PSPs are deemed excitatory if they increase the probability that an action potential will occur, and inhibitory if they decrease the chances". Inhibitory potentials can actually increase the chance of an action potential firing if the equilibrium potential for whatever ion flows through the receptor is in between the threshold potential and the resting membrane potential. Think about the GABA and Cl example we discussed in class. NeuroJoe (talk) 01:33, 8 May 2011 (UTC)

A more generalized introduction

It took a bit but I finally got the idea to this article--it explains why multiple contacts in quick succession from an ice cube or cold piece of metal feels like it hurts a lot more than just one every 4 or 5 seconds.

While it was easy enough to figure out, maybe the intro should be a little more.... reader friendly so we don't have to dig into the background to find out what we're reading about. Acid 1 (talk) 00:37, 8 September 2011 (UTC)

Newbie on wikipedia trying to contribute

Hello, thank you very much for your welcome and for your offer to participate as a result of my contribution to Neurotransmission. I would like to contribute, as well, to this new section. I am currently doing a PhD in animal behavior and welfare, so I am around these pages quite often, searching for links mainly. I am a veterinary surgeon currently working for the UK government, although my mother tongue is Spanish. I have noticed that there are not as many Spanish articles as in English, while Santiago Ramon y Cajal my champion in the subject, was the creator of the Neuronal Theory. I would like to help making the translation of some of this articles, but I don't really know how this works. We never know if another Spanish speaker only, would ever make another fantastic contribution to the neurophysiology science and I would like to help. Could you please give me some guidance? I am not even sure if this is the right way to ask about these things. Thanks GabrielFreiria — Preceding unsigned comment added by GabrielFreiria (talk • contribs) 13:08, 21 July 2012 (UTC)

Lead sentence calls 'summation' FREQUENCY; sb both temporal & spatial?

@NeuroJoe: (I understand that you didn't write the article, just soliciting input before I try to edit it.) The lead sentence seems to define summation as frequency summation, but since the action of summation in a neuron can be both temporal and/or spatial, shouldn't that fact be made clear to begin with? Intro read: "Summation, also known as frequency summation is the method of signal transduction between neurons, which determines whether or not an action potential will be triggered by the combined effects of postsynaptic potentials.".

And summation occurs within the neuron, at the axon hillock, not between neurons.

And is summation really transduction? The signal is electrical (graded) before summation, and electrical (action potential) after summation, so in that sense the nature of the signal isn't really changed, it's still electrical, in contrast to from chemical to electrical at input from synapse, and electrical to chemical at output at synapse. (talk) 10:15, 12 April 2016 (UTC) UnderEducatedGeezer

@Tryptofish, Looie496, and Lova Falk: Ok, if no one objects, I'll try to fix some of it?UnderEducatedGeezer (talk)

Thanks for the ping. This wasn't on my watchlist, but it is now. Yikes, what a mess! Basically, I agree with all of your concerns. It's really not about "frequency" per se, so I think that should be deleted entirely from the lead sentence. (If it's a redirect, that's not a problem.) And, yes, summation is entirely within a cell. It can occur at the axon hillock, where dendritic potentials summate, either to generate an action potential or not. But there is also summation at every postsynaptic membrane, including the end plate of muscle cells, where the effects of neurotransmitters are summated (summation of miniature postsynaptic potentials). And all of that is indeed electrical, not chemical, so this should not be labeled as "transduction" at all. --Tryptofish (talk) 19:03, 16 June 2016 (UTC)

@Tryptofish: Thanks for replying, I'm glad to see that I'm finally seeming to understand neurons a little better! And thank you also for the link to summation of neurotransmitters! I think I'd come across some mentions of miniature post-synaptic potentials, but hadn't paid much attention to them. Looks like they apply principally to muscle cells, but the general idea of variable quantity of released vesicles could relate to neurons too, maybe disease states? -- UnderEducatedGeezer (talk) 10:21, 17 June 2016 (UTC)

Oh, you are very welcome! The jargon is to call them end-plate potentials on muscle cells, and postsynaptic potentials on neurons, but mechanistically, they are the exact same thing. As for disease states, botulinum toxin is exactly that, and myasthenia gravis isn't exactly the same thing, but pretty close. (And, to a first approximation, cocaine and amphetamine affect related processes, although I'm oversimplifying there.) Bernard Katz won the Nobel Prize largely for discovering how these potentials reflect transmitter vesicle release. --Tryptofish (talk) 20:33, 17 June 2016 (UTC)