# Talk:Place cell

With respect to theta phase precession, the relationship between firing rate and theta phase is highly disputed. More research is required before providing a clear answer. Therefore, the uncoupling of firing rate versus theta phase was altered to include research articles that conflict with the findings of Huxter et al.
USER BIAS:
Again, PLEASE do not use this web-site for self-promotion. Users should provide an unbiased report of the field as it stands today. Remember, this is an encyclopedia. Not a blog. —Preceding unsigned comment added by ThetaMonkey (talk • contribs) 

(A wiki error plus an internet explorer problem just ate my long post here, so I must re-write it and will necessarily make it briefer than before. Drat!)
I think the current article focuses too much attention on hippocampal place cells. I propose the following:
1. Moving the phase precession section to a new article because many neurons show phase precession and some do not have spatial correlates (e.g. medial prefrontal cortex, Hyman et al. 2005, Jones and Wilson 2005).
2. Including discussion of spatial firing in other brain regions. Place cells are not as simple as "principal neurons found in the hippocampus that fire strongly when an animal, typically a rat, is in a specific location in an environment". There is much evidence that shows that there are non-spatial correlates of hippocampal place cell firing as well(Prospective/retrospective effects: Wood et al. 2000, Ferbineanu and Shapiro 2003, Bower et al. 2005. Non-trivial response to environmental changes: Lee et al. 2004, Leutgeb et al. 2005, Wills et al. 2005). More importantly, neurons with spatial firing correlates occur in other brain regions (dentate gyrus, subiculum, parasubiculum, entorhinal cortex, postrhinal cortex, lateral septum... refs available on request) and occur with their own set of interesting properties (grid-like firing fields, head direction correlates, context dependency, path-equivalence, etc).
If no one objects, I will go ahead and make these changes in a few days (keeping as much as the current content and wording as possible while doing so). Digfarenough 22:53, 13 July 2006 (UTC)

Just a thought... is it fair to say that "many neurons show phase precession and some do not have spatial correlates". Hyman et al. 2005 never showed precession (or atleast failed to mention the word 'precession' in their manuscript) and Jones and Wilson, 2005 do not show the best of examples. I am guilty of not reading closely and would appreciate some insight- how many of Jones and Wilson's prefrontal neurons precessed and how many did not? Could they achieved these results by chance? Did any neurons PRO-cess? To my knowledge, virtually all principal neurons in the hippocampus exhibit theta phase precession. So I guess what I am getting at is that it appears that precession is the "rule" in the hippocampus rather than the "exception" seen in the PFC.  ThetaMonkey 25 July 2006
I "deboxed" your question. You're right, I forgot that we didn't include any precession stuff in the Hyman et al. paper, but we did look for it and found some hints of it, but not enough to include. You're also right about Jones and Wilson not having the best of precession, but they do sort of show it. The only reference to number of cells on the Jones and Wilson paper that I can find is n=39 mPFC cells that showed phase shifts over space. I can't seem to find where they say the total number of cells recorded, though. Basically I agree with everything you say and I may have been a bit overzealous in making the claim of precessing cells without spatial correlates (I should at least have said clear spatial correlates, because some mPFC do show spatial firing to some degree). However, not all principal cells in the hippocampus show phase precession (look at the big two page figure in Skaggs et al. 1996 and you'll see a fair number that only fire at one particular phase and don't precess). It's also true that the Moser lab has reported that ECII cells but not ECIII cells show phase precession (two abstracts from SfN 2005, which they reference in their recent paper in Nature Reviews Neuroscience--I've only seen the abstracts though, not the posters so I don't know how good the data looks). My personal view (based on a new model I've been working on) is that precession is generated in ECII and HC just inherits it, but that is clearly speculative so I wouldn't actually add it to an article. So I basically agree with your last sentence there, but with the above slight caveats. Digfarenough 17:39, 25 July 2006 (UTC)

The Place cell article needs to improve citation of sources; it needs to use a standard citation format linked to a reference list. Also, care needs to be taken to explain jargon. --JWSchmidt 16:05, 18 July 2006 (UTC)

Please define: "a late phase" --JWSchmidt 16:52, 18 July 2006 (UTC)
Taken care of. I'll take a look at the references and see where else I can add some quick citations, if anywhere. Digfarenough 17:31, 18 July 2006 (UTC)

Jhuxter, you seem to disagree with the wording I used on an earlier edit, changing my wording of "the place cell appears to produce a rhythmic discharge of a slightly higher frequency..." to "the place cell produces...". I made that change because saying that it produces a rhythmic discharge makes it sound like phase precession is caused by the higher frequency spiking instead of the higher frequency spiking merely reflecting the precession. My interpretation of Zugaro et al. (2005) and Dragoi and Buzsaki (2006) is that precession isn't caused by an intrinsic mechanism in the hippocampus but rather by external input, which is why I prefer a wording that suggests that hippocampal place cells appear to produce higher-than-theta frequency spiking. Probably the simplest way to take care of this is to include a paragraph or two on putative mechanisms for the generation of phase precession, but I tend to lean away from including models from neuroscience in general. In summary: while it is true that mechanisms of phase precession were not being discussed there, I think it best to avoid wording that might lead to conclusions that are not supported by all the data, even if said data isn't actually discussed in the article. Digfarenough 18:38, 18 July 2006 (UTC)

Saying that the cells fire at a higher rhythmic frequency than the ongoing theta field oscillation is a simple statement of fact - it is not a comment on mechanism, but a necessary condition for phase precession to occur, and there's no avoiding it. This particular wording gives an alternative way of viewing the phenomenon, and to clarify for people who are less familiar with the concept of circular-linear correlations. That's why I considered your edit a bit misleading - nobody would dispute what the place cells are doing for it to be seen as phase precession - it's not controversial. I think the current wording of the last paragraph now makes it clear to the reader that the mechanism of phase precession is still under debate. Of course, we have not yet given adequate credit to any of the other models of precession - only the depolarisation model. If you would like to correct that particular imbalance...
J. Huxter
19/07, 2006

I am content with the current wording of the section, although it should be pointed out that the actual data presented by Harris et al. and Mehta et al (2002) are not in conflict with Huxter et al. 2003 - only the interpretation of the 2002 results. For example, the latter replicated the findings of Harris and colleagues with regards to instantaneous firing rate, and simply expanded on them to demonstrate that dissociation is possible both with and without experimental manipulation. That is why I edited the section referring to Huxter et al. as "a conflicting report". To date, there is no published data refuting the dissociation of firing rate and firing phase. That said, I'm perfectly happy to leave the mechanism of phase precession described as "unresolved". 
J. Huxter, 19/07, 2006

I'd like to add a list of things that should be added to the article- if you feel that something is missing, go ahead and add it. I'll try to take a shot at writing a paragraph for these topics in the next few weeks, but if you would like to go ahead and do it (which would be greatly appreciated), feel free!

Center of Mass Shift/ Place Field Assymetry
CA3 versus CA1 (similarities and differences)
A short discussion on the subiculum (as well as pre- & para-subiculum)?
Prospective / retrospective coding
Different types of Remapping (rate versus position) —Preceding unsigned comment added by ThetaMonkey (talk • contribs) 
Related to remapping, Gothard et al. (1996)'s reference frame remapping (the linear track example is pretty easily explainable) showed some interesting results. One thing that I think is often underemphasized is that while place cells have stable place fields, the cells appear to be somewhat stochastic in that it is not uncommon for a cell to hardly fire at all on some passes through the field. I think perhaps the beginning of the article should be slightly changed to reflect that (as it is it sounds like a place cell always fires strongly whenever the animal is in the cell's place field). I'll be out of town for a week, which might actually give me a chance to make a few of these changes to the article. digfarenough (talk) 21:37, 7 August 2006 (UTC)

Concerning the suggested changes under "Article Needs Expansion":

1. moving phase procession. I agree.
2. Including discussion of spatial firing in other brain regions.  Be cautious. Over the years I've seen far too many references to spatial correlates as spatial signals. A correlation is not a code. I suspect that if you recorded in any region of the brain you'd get a weak but reliable spatial correlate. I don't recall ever hearing a formal definition of a "place cell", but, at a minimum, the cell must have a spatial correlate that is not secondary to other correlates. Since it is extremely difficult to show that a correlate is not secondary to other correlates (e.g., spatial view, locomotion, theta, arousal, fear, brightness) weak correlates should be rejected as candidates. Please don't call all cells with spatial firing correlates "place cells". I agree that the assertion that place cells are pyramidal cells is wrong. I can't recall anyone has ever saying that in the way this article does.
I'm trying to avoid the "self promotion" directive above, but I think the citations do a disservice to the place cell work that comes from Brooklyn. There is not a single reference to Muller, Ranck, Kubie (me), Fox, Fenton, Quirk, etc. Many of the assertions in the article are solid, and, I feel, should use citations from the Brooklyn group. Moreover, many of the citations are weak. I don't have time right now to work on citations. I'll try. But I'd like to see them edited.
Another comment. Overall, I don't think this article would help someone with no background. The choice of figures is poor. There should be at least one firing rate map. The phase procession figure, while pretty, is very hard to figure out. The Golgi image of a hippocampal pyramid, while pretty, doesn't do much. The complexities of extra-cellular recording (where you can't see what you are recording! ) are not clear.
The article is extremely weak on theory. In the first few sentences there is reference to the "cognitive map" theory. In the phase procession paragraph there is a reference to how phase procession could help with localization. Other than that, nothing. I think more should be said about how the set of hippocampal neurons might work in aggregate, both in terms of computation of location and, potentially, other functions. The article is extremely dry without theoretical frameworks or suggestions of significance.

John Kubie
Chachaq 14:43, 17 September 2007 (UTC)

Hi John. I've moved this comment to the bottom of the page, where new sections are traditionally added. It's true that place cells historically are characterized as having primarily spatial correlates (and usually other requirements such as a certain level of spatial information or sparsity, a threshold number of contiguous spatial bins with elevated firing rate level above the background rate, etc.). It is hard to decide whether any cell has a primarily spatial correlate, except in particular controlled experiments, and it certainly seems reasonable to me that a given cell might have spatial correlates in one experiment and nonspatial correlates in another and hence would be sometimes a place cell and sometimes not. Consider the results over the past few years on context-dependent firing of CA1 units (Wood et al. 2000, Bower et al. 2005, to name just two). Is a cell that doesn't always fire in its place field a place cell?
Regarding your other point, it's certainly true that no one from that group is cited, and that's rather surprising. You should certainly feel free to add references for any work that you like. If anyone feels that you're overstating things, they'll likely change it or call you on it. Also, if you have a rate map image that you'd like to release into the public domain or license under a free license, certainly feel free to add it. At some less busy time in my future I'll try to work on this page some, but there are others that are in worse condition, so it isn't a large priority for me. digfarenough (talk) 20:30, 17 September 2007 (UTC)

The articles claims that "In any particular environment, roughly 40-50% of the hippocampal place cells will be active". I don't think this is correct. A simple neural network model of the hippocampus suggesting its pathfinding role in episodic memory retrieval claims the number is closer to 0.1-1 % and Ensemble dynamics of hippocampal region CA3 and CA1 doesn't even mention this. And quite frankly, 50% is extremely high, even to the casual observer Paskari (talk) 21:15, 5 December 2009 (UTC)

Sorry, it turns out in A simple neural network model of the hippocampus suggesting its pathfinding role in episodic memory retrieval they claimed that 0.1-1% of the cells were active at a particular location in an environment, not the entire environment. Paskari (talk) 21:32, 5 December 2009 (UTC)
It actually depends on the size of the environment -- in a large enough environment, the great majority of cells will have a field somewhere.  The 40-50% figure is a reasonable approximation for dorsal CA1 cells in the environments typically used for recording, which tend to be around 1 meter across or less. Looie496 (talk) 05:31, 6 December 2009 (UTC)
I agree with the above statement- completely environment dependent. If I am recording from a rat in a shoebox, I'd imagine that I would be lucky to see one cell active. If my rat, however, ran through an aircraft hanger, I wouldn't be surprised to see most every cell fire. Although our paper was quite inaccessible, we compared the proportion of cells active in the extreme dorsal and middle hippocampus (Maurer et al., 2006) noting a dramatic difference within an environment of a fixed size. ThetaMonkey  —Preceding undated comment added 22:27, 23 February 2010 (UTC).

Removed the external links. Both were dead
I will be editing this article from 10/11/13 to 12/7/13KerzNeuroscience (talk) 19:09, 11 October 2013 (UTC)
Students from Middlebury College will be editing this page from 10/11/13 to 12/7/13 cabbadi ( talk)  —Preceding undated comment added 16:08, 12 November 2013 (UTC) 

This article is part of a larger project by students at Middlebury College. We will be working on this page from 11-12-13 to 12-12-13. 
Middlebury College Wepage

Very complete page, nice work! Very extensive research descriptions so I can tell you guys did a great job of looking up sources to properly understand how place cells work. I suppose it would have been better to include (if possible) research involving humans. 
My main issues with it are in terms of what topics you group together: in background i'd expect to see a more extensive history of the discovery, its why and how, and the theories that preceded it. That being said you might have been working with little available information in that respect.I feel that the different parts of the page were categorized according to terms (like Place Fields, Sensory Input, etc) instead of something more straightforward like function, areas involved, etc. I find the structure of the background section a little confusing, in terms of your bouncing back and forth between the studies you describe and the actual information those studies divulged. I'd also edit the article to make it more fluid-sounding and get rid of awkward phrasing. 
Other than that, nice visual aids, great section on abnormalities! 
Chabz333--140.233.137.50 (talk) 03:45, 26 November 2013 (UTC)
General Intro
•	2nd paragraph – reread for grammar and other small errors
•	In your definition of attractor dynamics,  it is unclear if it is referring to 
how they work within place cells or the general definition. 
•	Nice clear 3rd pharagraph in Intro. Consider saying what is involved in the circuit that “informs place awareness and place memory”. 
Background
•	After first paragraph maybe sum the findings of John O'Keefe and Lynn Nadel’s study and replace, “For more information on studies with rats, see below.”  With a new sections titled “studies” or something of that sort. It is easier to find in the text that way.
•	Look at clarifying description of the delayed non-match-to sample task. Try to use very specific language (especially in the last couple sentences).
•	Unclear: “Lesioning experiments attempting to inflict non-spatial memory deficits in the hippocampus have either failed to induce a deficit or induce a deficit using lesioning methods that affect more than just the hippocampus.[14’
Place Fields
•	Consider new pic of the hippocampus, this kind of looks like the amygdala in this photo.
Sensory Input
•	Nice section
Olfactory cues
•	Interesting first study mentioned
Effects of Ethanol on Place Cell Function
•	In the last paragraph you say “Future research should investigate whether chronic ethanol exposure produces a functional tolerance to ethanol’s effects and whether there is specificity of place cell firing during the formation of this tolerance.” This seems contradictory to what you said in your second sentence of this section, “Just as lesioning in these structures causes rats to rely on cue-based information to function, so too does chronic ethanol exposure.[29]” Maybe join two idea together to clarify the relationship
Diseases Affiliated with Place Cells
•	In the last sentence of the first paragraph, “O’Keefe who originally found the existence of place cells said that, “We suspect we’ll begin to see signs of changes in the functions of cells before we see changes in behavioral tasks."[40], consider removing, that before quote.
General Feedback
•	Nice draft. Besides the small comments I made on specific sections, you might want to address how much, or if any research has been done on humans. If there is any discussion on humans in your article make sure to make that very clear.  — Preceding unsigned comment added by MarMarBla123 (talk • contribs) 15:01, 24 November 2013 (UTC) 


### Peer Review 2
Wow, there is a lot here guys, great job! I like how in depth this page is and how many resources were referenced. It shows all of you really did your research. Most of my edits are minor details. In terms of context, I think some areas are a little repetitive and it might make sense to restructure some of the sections. The first paragraph clearly lays out the topic and I get a good sense of what the page is going to be about. The first sentence of the second paragraph seems repetitive. Maybe instead explain what a firing field is.  In the next sentence I think you want to say “studies with rats have shown” not show. The rest of the second intro paragraph is great, it explains cognitive maps very well. The quotes in the last sentence are a little confusing. I think if you are going to use a footnote it would be easier to read if you paraphrased. Otherwise the source of the quote should be introduced. The only thing in the third paragraph is that the second sentence:” Place cells fire when an animal is located in parts of the environment known as place fields,” seems repetitive of the second paragraph. 
Great Background. I don’t know if this is relevant but I would be interested to know more about the discovery. For example, how did O’Keefe discover the existence and location of place cells? What method were they using? I think in the third sentence you mean have not has. “The rat hippocampus was biologically designed to provide the rat with spatial information.” This is really interesting but needs a citation or further explanation. I really like the link describing place fields! It helped me understand the directional piece of place cells. I think you could even put this whole section above background because you reference these concepts in the background section. 
The sensory input section is clear and really interesting. Especially the part about olfactory cues! The Abnormalities section is also really well done. I think the only area that was hard to follow and a little repetitive was the ethanol section. Are there other studies with other gases or just ethanol? Other than that, this is really well written and I enjoyed reading it. I don’t think too much needs to be changed or added. 
|Maddierawding  — Preceding unsigned comment added by 140.233.136.61 (talk) 00:47, 26 November 2013 (UTC) 


### Peer Review 3
You guys did an awesome job, this page is incredibly extensive and well researched! I’m blown away at how many references you have. Since this page is so well done I don’t think much needs to be added, all my edits are very minor. 
The first paragraph was very comprehensive of the whole topic, well done! Minor edit: in the first paragraph, you need a period between “re-mapping” and “And”. In the background section the first two sentences are a little bit repetitive. I also think that you should start the Background with “Place cells” not “These cells”. Again, a very tiny detail. Also in the third paragraph of the Background the last line says “does not does not”. I think you should also stay consistent with either bolding or italicizing words. Also in the Background, when you discuss rats briefly and then say "see below" for more info, it is definitely unclear where to look below, so either just go ahead and get rid of that or just make sure it's more obvious. 
In the Abnormalities section was very well done, it was really extensive about all the different abnormalities that could occur. In regards to the Ethanol section, in the last sentence, “Research should also be done on whether chronic ethanol exposure produces a tolerance to other abused drugs with similar properties”, does this mean that they have only tested for ethanol? Or have other drugs been tested? Also in the Vestibular Lesioning section, is it possible to be more clear about what a vestibular lesion is? 
Overall this page was great, really long and definitely in-depth. I’d just read over it again to make sure there aren’t more grammatical errors, and just get rid of any repetitive sentences. Awesome job! 
Hasstheboss (talk) 01:44, 26 November 2013 (UTC)


### Response 1
Thank you for your comments and advice! We appreciate the feedback and have begun to incorporate your suggestions into a better, more informative page. We have clarified some of the information in the "Abnormalities" section, and have cleaned up some of the grammatical errors in earlier sections. Additionally, we have added more links to other Wikipedia articles and have described some of the images used in greater detail. We probably won't change the image of the hippocampus, because although the image does also include the amygdala, we feel like this won't be a necessary distinction for the general public and the 3-d rotation of the image is really helpful. We are still working on the introduction and background sections, and are most likely going to be removing some of the information here that is repeated later. Thank you so much for your help, and please feel free to comment further! Abbychick (talk) 14:46, 5 December 2013 (UTC)


### Response 2
Thank you for all of your comments! They were incredibly helpful. Below you will find all of my changes to my sections of the Wikipage based on the comments made in the Place cell talk page and my professor’s comment in my user sandbox--
Comments on my portion of the Background section:
- Look at clarifying description of the delayed non-match-to sample task. Try to use very specific language (especially in the last couple sentences).
My changes:
To clarify my description of the delayed non-match-to sample task, I deleted the last couple of sentences and replaced them with more specific language (as seen in bold below) that includes an example of what a visual representation might look like (a block). 
This task uses flexibility in that the rat is first presented with a visual representation such as a block. After a delay, when presented with the block and a novel object, the rat must choose the novel object in order to obtain a reward. 
- Unclear: “Lesioning experiments attempting to inflict non-spatial memory deficits in the hippocampus have either failed to induce a deficit or induce a deficit using lesioning methods that affect more than just the hippocampus.
My changes:
In order to clarify this part, I broke it up into several sentences that have more clear wording and are easier to understand.
Many lesioning experiments attempting to inflict non-spatial memory deficits in the hippocampus have been unsuccessful. In some cases, lesioning has been successful in inflicting non-spatial memory deficits, however, other structures besides the hippocampus were affected by lesioning. Therefore, the rat’s non-spatial memory deficits could have been unrelated to place cells.
-In the last paragraph you say “Future research should investigate whether chronic ethanol exposure produces a functional tolerance to ethanol’s effects and whether there is specificity of place cell firing during the formation of this tolerance.” This seems contradictory to what you said in your second sentence of this section, “Just as lesioning in these structures causes rats to rely on cue-based information to function, so too does chronic ethanol exposure.” Maybe join two idea together to clarify the relationship.
My changes: None. I did not make any changes because I do not see these sentences as contradicting one another. Reliance of cue-based information to function after chronic ethanol exposure does not necessarily mean that functional tolerance has developed. More research would have to be done to determine whether tolerance has developed and if so, whether place cell firing changes during the formation of the tolerance.
-In the third paragraph of the Background the last line says “does not does not”.
My changes: I fixed this typo.
-“The rat hippocampus was biologically designed to provide the rat with spatial information.” This is really interesting but needs a citation or further explanation.
My changes: I completely agree with this comment. The way I phrased this sentence made it seem like it was a fact that would need much more explanation when I meant to say that supporters of the cognitive map theory believe that the rat hippocampus was biologically designed to provide the rat with spatial information. Therefore, I combined the sentence mentioned above with the previous sentence to make it clear that it is a theory associated with the cognitive map theory. I also provided a citation at the end of this sentence as is suggested.
Comments on the Abnormalities section:
-I think the only area in the Abnormalities section that was hard to follow and a little repetitive was the ethanol section. Are there other studies with other gases or just ethanol?
AND
- In regards to the Ethanol section, in the last sentence, “Research should also be done on whether chronic ethanol exposure produces a tolerance to other abused drugs with similar properties”, does this mean that they have only tested for ethanol? Or have other drugs been tested?
My changes: I deleted the following sentences seeing that they were a little bit repetitive and unnecessary: Interestingly, studies have shown that repeated exposure to ethanol leads to a similar shift in the rat's needing to rely on non-spatial information to assess its surroundings. The behavior following repeated ethanol exposure can be explained, in part, by changes at a cellular level. Ethanol greatly alters the firing of hippocampal place cells. I also deleted “and before testing on tasks" because I think it makes the argument harder to follow. I also made the following bolded changes: “Research should also be done on whether chronic ethanol exposure produces a tolerance to other abused drugs with similar addictive properties. While research has been conducted on the effects of addictive drugs on spatial memory, there has not been research that investigates whether chronic ethanol exposure would produce tolerance to these drugs in addition to ethanol tolerance.” I added the word “addictive" to be more specific about what “similar properties” means. I also added a sentence at the end of the paragraph explaining what has been researched in terms of the effect of addictive drugs on the hippocampus and what should be researched in the future.
-In the Vestibular Lesioning section, is it possible to be more clear about what a vestibular lesion is?
My changes: I added a description of the vestibular system as part of the labyrinth of the inner ear to clarify which structure I am discussing and where it lies in the ear. The “Vestibular system” is also linked to a Wikipedia page so that further research on the vestibular system can be conducted if the reader is interested. I also described lesioning the first time it is mentioned in our article and added a link to the Wikipedia page on lesioning the first time it is mentioned so that readers who want to learn more about what it is can explore that link. 
-Comment from Professor Cronise: make sure that you have linked to other pages throughout your section at all opportunities--remember if it is linked earlier in the actual page for place cells, don't link to it again.
My changes: I went through and added the following links to the already existing links in my sections (see below)
Under introduction:
Cognitive map link to Cognitive map (this is under my partner’s section, but I later mention cognitive maps and wanted to make sure it was linked when first mentioned
Pyramidal link to Pyramidal cell (this is under my partner’s section, but I later mention pyramidal cells and wanted to make sure it was linked when first mentioned)
Under background:
non-spatial memory link to Spatial memory
Delayed non-match-to sample task link to Match-to-sample task
Trauma link to Trauma
Omnidirectionality link to Omnidirectional
Goal-oriented link to Goal-oriented
Landmarks link to Landmark
Cue link to Sensory cue
Under Effects of Ethanol on Place Cell Function:
Chronic link to Chronic
Ethanol link to Ethanol
Tolerance link to Alcohol tolerance
Addictive link to Addiction
Under Effects of Vestibular Lesioning on Place Cell Function:
Inner ear link to Inner ear
Self-motion link to Self-motion
Bilateral link to bilateral
Connectome link to Connectome
Neurotransmission link to Neurotransmission
Neuroanatomy link to Neuroanatomy
Protein expression link to Protein expression (biotechnology)
Under place cells and aging:
Pharmaceuticals link to Pharmaceutical drug
Protein synthesis link to Protein biosynthesis
Senescence link to Senescence
Frequency link to Frequency
Translation link to Translation (biology)
Transcription link to Transcription (genetics)
mRNA link to Messenger RNA
Memory consolidation link to Memory consolidation
CA1 link to Region I of hippocampus proper
CA3 link to Region III of hippocampus proper
CA2 link to Region II of hippocampus proper
Deficits link to Cognitive deficits
Amplitude link to Amplitude
Plasticity link to Neuroplasticity
Glutamate receptors to Glutamate receptor
Antagonist link to Receptor antagonist
Encoding link to Encoding (memory)
Neurogenesis link to Neurogenesis


### Response 3
In response to several comments that the background section, specifically discovery of place cells should be expanded on, I added a paragraph in the background section on studies that have proven the information we can now conclude on place cells:
After O’Keefe and Dostrovsky first found the existence of place cells within the hippocampus in 1971, they conduced a study five years later with rats that demonstrated these place cells would fire whenever the rat was within a certain place in the environment [8] . This was one of the first indications that place cells were related to spatial orientation. They also discovered that space cells fired in different areas of the hippocampus depending on where the rat went, and this whole firing network made up the rat’s environment (O’Keefe 1976, Wilson & McNaughton 1993). As environments changed, the same place cells would fire, but the relationship and dynamic between firing fields would change (O’Keefe & Conway 1978). Therefore place cells are thought to give humans and animals a guide to the environment it is navigating and its position in that environment. Place cells are generally observed through recorded action potentials. As humans or animals navigate large environments and then arrive at a particular location, there is a notable increase in the place cell firing rate once that specific location has been reached (Eichenbaum, Dudchencko Wood, Shaprio and Tanila, 1999). For more information on studies with rats, "Place Cells and Aging".
I researched more to find information on the specific study that O'Keefe and Dostrovsky conducted in 1971 to find place cells, but I found very little information on this topic. Therefore I instead added the paragraph above to give more background on the research conducted. 
Likewise, in the "Abnormalities" section I removed the study by Ming Yi because it is not a peer-reviewed article.
Also for more clarity, I changed the sentence that reads "for more information on studies with rats, see below" to  "for more information on studies with rats, see the section 'Place Cells and Aging'" so the reader would know where to look, specifically.
cabbadi (talk) 16:32, 8 December 2013 (UTC)

https://knowingneurons.files.wordpress.com/2013/04/place-cell-animation.gif?w=1000&h=607, linked in the Place Field section, purports to show the activation of place cells as a rodent moves through physical space. Unfortunately, the place cell physical geometry in the animation mirrors the physical world geometry. This seems completely wrong: no research I've seen suggests this. It makes it look as if place cells in the hippocampus are behaving like a miniature paper map corresponding to the environment (with all the implied path integration data just exposed as physical place cell relationships.)  This seems to me to be just leading the reader to an incorrect mental model of how place cells work. Update: papers refer to this as a topological map versus a topographic map. text/link removed. 
MichaelNaunton (talk) 15:05, 16 September 2019 (UTC)

I agree with your deletion of it. If nothing else, the way that it was presented in the text was clearly spammy. --Tryptofish (talk) 22:17, 9 October 2019 (UTC)

This article feels a bit like a hodgepodge of all kinds of information. I'm going to try to rework it so that it flows a lot better, but still contains all the relevant information. I think it would be great if this article could get to GA status. Might take a while though, so bear with me. If anybody wants to help and/or has suggestions, please let me know. Achaea (talk) 20:04, 27 December 2019 (UTC)

This review is transcluded from Talk:Place cell/GA1. The edit link for this section can be used to add comments to the review.
Reviewer: Chiswick Chap (talk · contribs) 20:56, 6 January 2020 (UTC)


### Comments
Well it's a very nice article on a significant topic.

I'm a bit concerned about the high number of WP:Primary articles: out of 69 sources, only 7 (at a glance) appear to be definite secondary review papers. Wikipedia more or less defines Reliable Sources as being secondary; while primary sources are not forbidden they are to be used with care, which does rather imply "sparingly", hardly the case here. The serious risk with the use of primary research is that one paper frequently contradicts another, and there are only 2 ways those contradictions can be resolved: by relying on a reliable secondary review that discusses both papers; or by making an editorial judgement (WP:OR) or synthesis (WP:SYNTH) which is not allowed.
Very good point, I indeed often cited the original sources. I have started adding secondary sources, would it be good practice to remove primary sources where I can find a secondary source? Or shall I keep both in those cases?
Thanks. It's a matter of judgement. When a secondary source adequately covers several primary sources, they can be dropped (probably best to do so). On the other hand, to write about evolution and Darwin without citing Darwin 1859 would look strange; so the rule may be to cite the key primary papers that created a field, and then to rely on secondary sources as far as possible. At the other end, if something is conjectured based only on one recent primary source, we should mention it, if at all, only with several pairs of thick gloves on ("a recent conjecture ...").
Many thanks for the new secondary sources.
The whole of the first paragraph of "Aging" is uncited, as is some of the second paragraph.
Now cited with a review paper
The last sentence of "Reactivation, replay, and preplay"  is uncited.
Now cited with a review paper
I'm surprised there are no diagrams of place and grid cells showing their interaction.
I have a found a diagram for this, will work on writing in the relationship between place cells and grid cells and add the diagram at that point.
Have added diagram, let me know if this is sort of what you had in mind. It doesn't really show the interaction but is a nice overview.
I'd agree with that. Room for post-GA improvement!
Similarly, "Remapping" is crying out for a diagram (a map?) showing the changes that occur. I visualise this as moving the map so a different 10x10 square gets covered by the hippocampus's magnifying-glass, and that could indeed form the basis of a simple cartoon-diagram, but there are other options. It's a very striking finding that remapping occurs, and since it's basically spatial it really deserves a spatial representation. It's more than possible that the artwork in some paper is CC-by-SA; if not, we can easily redraw something that's out there.
I'll try to make a nice diagram for this, good point!
Made remapping diagram
Many thanks, but please leave striking out my comments to me, I have to decide if the comment has been satisfied, or not.
Sorry, wasn't sure, won't do it again!
"a model known as the functional differentation model" - why not drop "a model known as". The term (FDM) seems to be linked at least half-wrongly; functional differentiation may be key to the model but is not the whole story, not least because it has nothing to do with biology! At the least, change the link to just the words "functional differentiation", but that leaves the term more or less unexplained: what is the connection between the maths and the structures? Something (a map of the brain?, a diagram?) is missing here.
Have dropped the phrase you suggested and removed the link (was definitely not right). I added the link by saying the compilation of inputs from downstream areas is a functional derivative of the original inputs, which is what the name of the model refers to. Will think about how I can phrase that better though.
"Metric and contextual inputs are processed together in the entorhinal cortex before reaching the hippocampal place cells." This would seem to be an ideal place for a map of the brain highlighting (in colour, say) the entorhinal cortex and the hippocampus.
Couldn't find a good enough one, but will have more of a search.
Found quite a good imaging showing the anatomy and colour. Not quite with colour what you suggested, but I think it does illustrate the point quite well.
Grid cell seems misplaced in "See also". I suggest a cited paragraph on grid cells in "Background" indicating the relationship to place cells.
Will do, really great suggestion!
Done
"The ability of place cells to incorporate new movement information is called path integration". How does that square with what's written in that article: "Path integration is the method thought to be used by animals for dead reckoning." I can see the two statements might have some connection but that will need some explaining, no?
Good point, need to have a look at that.
That sentence was wrong and not what was in the source, have fixed that now.
Well, the article is well up to the required standard by now. I hope you feel that the review has improved the article, and I hope you will take the time to pick one or two articles from the GA nominations list to review yourself. All the best, Chiswick Chap (talk) 10:17, 19 January 2020 (UTC)

The review has definitely helped, thanks so much for all your input! Achaea (talk) 10:23, 19 January 2020 (UTC)

I've just edited the subsection Relationship to grid cells, and will make a few tiddly changes more broadly in the article. I'm a non-expert, so expert editors may want to review my copy-editing. I was drawn here after reading the article on the entorhinal–hippocampal system in the most-recent Scientific American, which describes evidence that the system may function to help us navigate social relations (no mention of that here); the SciAm article does not clearly explain the difference between grid and place cells—in particular why we need both, and why grid cells are arranged hexagonally. This subsection does a better job of that, but I still don't think I've grasped current knowledge on the functional distinctions. Tony (talk) 07:04, 4 February 2020 (UTC)

Hi @Tony1:! I reviewed the changes, that's all fine. There's still a lot of discussion in the field as to why we need both and what their relationship is. Some theories suggest that place cells are derivatives of grid cells, so that grid cells are necessary to create place cell behaviour. Others suggest that grid cells rely on place cells. I think we need to make sure this is clear in the article, and we don't give one side undue weight. I have avoided that so far by not going too much in it, but it could definitely benefit from a bit more depth! Achaea (talk) 12:56, 4 February 2020 (UTC)