Talk:Evoked potential

Introductory sentence

Similar to the discussion in Talk:Visual_evoked_potential, can the "In neurophysiology" phrase be removed from the opening sentence? Edwardian 04:18, 7 August 2005 (UTC)

Yes. Whether neurophysiology or not, an evoked potential is always the same thing. Dontaskme 22:52, 12 September 2005 (UTC)

Good argument. No protests. I'll do it. Lova Falk (talk) 19:52, 14 May 2008 (UTC)

EEG includes EPs

The article currently suggests that EEG and evoked potentials are completely unrelated. My understanding is that evoked potentials are a component of the EEG. In other words, the EEG is a mix of (a) the evoked potential, (b) spontaneous/ongoing/"background" activity, (c) misc. other things, (d) possibly interactions between the aforementioned components. The article should at least reflect that the EP is a part of the EEG. Dontaskme 22:49, 12 September 2005 (UTC)

Both components are in the EEG, if you mean the actual voltages on the skalp, but the displayed measement results are distinct: You (usually) can't see the EP in a display of EEG traces as it is so much smaller, and you can't see the (background) EEG in an EP display as it averages out. I'll try to clarify this in the article. --Pjacobi 08:17, 13 September 2005 (UTC)

I meant exactly what you are saying. An EP usually cannot be identified in an EEG trace, but it's nevertheless hidden in there (and can be extracted through averaging of multiple trials). Dontaskme 18:41, 13 September 2005 (UTC)

I appreciate the talk, but you should write info in the article, not in the talk page. Yoiu17 06:41, 13 December 2006 (UTC)

Evoked Potential Synonymous with Event-Related Potential

According to Steven Luck (MIT Press 2005), and also just about everyone else who writes on this, "evoked potential" is just an outdated term for event-related potential (ERP). The two articles should therefore be merged. The article on wikipedia is out of step currently with widely-used terminology as it suggests that evoked potentials differ from ERPs in that they are sensory and stimulus-linked. This is what is commonly called an "exogenous" ERP, where as an endogenous ERP is one that depends more on organism factors than on environment factors.

In a sense, EPs and ERPs are the same thing, though "endogenous," long-latency components (used in cognitive studies) are usually referred to by the term "ERP," while "exogenous," short-/mid-latency VEPs, AEPs/BEARs and SSEPs (used to test the functional integrity of sensory systems) are always referred to as "EPs." "ERPs" often get referred to as "EPs," while I don't think anyone would call a VEP an "ERP." (I.e., I don't think anyone would say, "I just sent my patient to get a visual event-related potential to rule-out optic neuritis," while a cognitive research might in fact say, "I used to do fMRI, but now I am getting into evoked potentials.") Luck's book doesn't address those things which are called "EPs." (For that, see Fisch and Spehlmann's EP Primer or Chiappa's EP in Clinical Medicine.) I don't have a strong opinion about merging the articles, but I just wanted to share my perspective on the semantics. Shwmtpf 07:01, 30 August 2007 (UTC)

Certainly anyone searching should/would use event related potential as term? —Preceding unsigned comment added by Drrjagger (talk • contribs) 18:18, 27 February 2008 (UTC)

No, anyone searching can find the term evoked potential in a text (I did) and wonder what it is. However, that's not an argument for keeping two articles, because evoked potential could easily be redirected to event-related potential. Lova Falk (talk) 13:10, 19 April 2008 (UTC)

Just a brief comment: "evoked" is also opposed to "induced" in the field of EEG and MEG research. Induced is generally used for neuroelectric activity that is not phase-locked to a stimulus but still time-locked to it so that it may be seen by averaging the envelope of filtered EEG/MEG but not in the average of the signals themselves. cf. http://kurage.nimh.nih.gov/meglab/Meg/InducedEvoked knd (talk) 23:01, 8 May 2008 (UTC)

• After having done some thinking, I'm in favor for merging these articles, especially if in the new article the ways in which EPs and ERPs are the same and are different are pointed out, because that would lead to a greater clarity. Lova Falk (talk) 19:45, 14 May 2008 (UTC)

I totally concur with what Shwmtpf and Lova Falk have just said. Being myself in the field, I would also suggest to rename the whole page to event-related response, since in magnetoencephalography one cannot precisely speak of potentials but of magnetic fields, so that evoked fields and event-related fields are use with a perfect correspondence with their EEG analogs. Moreover, the term event-related is also used in the context of fMRI to describe the hemodynamic response to a stimulus (as well as the way to design an experiment were those responses can be measured). In single-unit electrophysiology, one speaks of "peristimulus histogram" with the very same meaning. Finally, I also find event-related more transparent: evoked (despite its professional use) might sound fuzzy to the naive reader (that's why the term must appear and be described in this page). knd (talk) 11:18, 4 October 2009 (UTC)

The two terms don't really mean quite the same thing. An evoked potential is one that results from some action taken by the experimenter; an event-related potential is associated with some event, which may or may not be generated as part of an experiment. Also, in animal research it is common to deliver stimuli using implanted electrodes -- the brain waves that result are called evoked potentials but not event-related potential. Even so, I don't think there is a really strong argument against merging the two articles. Looie496 (talk) 13:26, 4 October 2009 (UTC)

So is the conclussion that we should these two articles? I think that would be a good idea. — fnielsen (talk) 14:34, 30 October 2013 (UTC)

I believe merging the two articles is not a good idea. VEP, VECP, and EP are the terms commonly used and well established in sensory physiology, neurology, ophthalmology, vision research and perception research. The term ERP seems to be mostly used in the cognitive sciences. The terms EP and ERP are related but mean different things and have a different history and emphasis. The current article is rather long already and still misses important developments (e.g. the multifocal EP). The classic transient VEP is missing altogether (P100 etc.). Better structuring would be a good idea, though, and there should be more cross links to the ERP. Strasburger (talk) 10:10, 23 June 2015 (UTC)

I tend to agree with that. However, since the argument is that some EP technologies do not fit under ERP, then this page should only cover these technologies. The other cases, which fit under ERP, should go in the ERP page. It will be nice to find a reference where some specific EP technology is discussed as not being an ERP technology. Unfortunately, this seems to be a matter of common usage that is not necessarily made explicit in the literature. Wikipedia might not be the place to make it explicit. — Preceding unsigned comment added by 198.251.62.95 (talk) 06:52, 29 January 2017 (UTC)

I would move the section auditory evoked potential under auditory event related potential, because it seems to fit under ERP. For example, in http://www.brainvolts.northwestern.edu/documents/Kraus_Nichol_Encyclo_Neurosci_AEPs.pdf both are said to synonymous. It's a question of usage, because the concepts are the same, and this reference seems reliable as far as usage is concerned. — Preceding unsigned comment added by 198.251.62.95 (talk) 07:00, 29 January 2017 (UTC)

The terms event-related potentials (ERPs) and evoked potentials (EPs) are not synonymous. This is true for all the main sensory modalities – vision, hearing, touch, smell, taste (EPs have been recorded for all modalities). The event in an ERP can be internal or external, whereas in an EP it is external only. The term ERP was introduced as a means to generalize the EP concept to cognitive events, as was required in the cognitive sciences. Consequently, it is mostly used there and for internal events only.

The evoked potential, in contrast, is the standard term for the perceptual and sensory sciences, including their medical branches (ophthalmology, audiology). The EP has important clinical applications (VEP, BERA, AEP). In these fields one would not call it an ERP. Even the cited neuroscience page refers the reader to the EP page in the auditory case – not because the terms are synonymous but because there is no clinically important cognitive counterpart to the AEP (i.e., with an internal event). Strasburger (talk) 11:46, 29 January 2017 (UTC)

Subtopics with separate pages

I think there are links to several pages with subtopics that possibly do not merit their own pages until expanded sufficiently. Kpmiyapuram 13:51, 29 August 2007 (UTC)

I do not agree that the two pages be merged. Evoked potentials include measuring EMG (peripheral muscle response) whereas ERPs are limited to measuring brain responses. Hdesousa (talk) 22:18, 2 February 2008 (UTC) Hansel de Sousa

Multiple Sclerosis?

Would a section on the diagnosis of MS be appropriate here? Jobonki (talk) 17:12, 4 September 2016 (UTC)

A section on EP applications would be good, IMO, and in there, the application of the transient VEP for MS diagnosis should be mentioned. Strasburger (talk) 09:02, 5 September 2016 (UTC)