Talk:Dopaminergic pathways

@Petergstrom: You need to stop being so defensive of content that you add and start listening to constructive criticism, because trying to fix issues with inaccuracy (verifiability) that you repeatedly introduce is seriously annoying me. This table is not accurate because it suggests uniformity in the inputs to every brain structure which contains dopaminergic nuclei, it's not comprehensive because it's missing important inputs to the VTA (e.g., orexinergic projections from the lateral hypothalamus; that said, I have to give you credit for covering the GABAergic inputs from the RMTg - the importance of that nucleus was identified only recently so a number of refs don't cover it) and other dopaminergic cell groups, and most important of all, it fails verification because the source you cited literally illustrates that the inputs to the VTA and SNc are not uniform in a diagram.

I am not deleting the table because I think that this content should not be covered. I am deleting it because you are not accurately covering this content in a manner that is consistent with the cited source and other neuroscience reviews on this topic. Inputs are usually covered in articles on brain structures, not neural pathways, but that convention doesn't mean that this content shouldn't be added in this article. If you want to add it here, cover this material correctly by partitioning the inputs according to each dopaminergic projection nucleus:^[1]

• cell group A16 corresponds to the olfactory bulb
• cell groups A11–A15 correspond to hypothalamic nuclei, including the preoptic area, paraventricular nucleus, and adjacent regions within the hypothalamus
• cell group A10 primarily corresponds to the ventral tegmental area, although some surrounding structures (e.g., the nucleus linearis) also contain dopaminergic neurons and are classified as part of this cell group
• cell group A9 corresponds to the substantia nigra pars lateralis and pars compacta
• cell group A8 corresponds to a structure termed the "retrorubral field", which we don't currently have an article about.

These cell groups are the dopaminergic nuclei that give rise to every dopaminergic pathway in the brain. This article currently covers most of the pathways associated with cell groups A9 through A15.

Lastly, the only neurochemicals in that table that only function as excitatory neurotransmitters and inhibitory neurotransmitters are glutamate and GABA, respectively. Do not generalize or make inferences from sources based upon what you read - doing this constitutes WP:OR. The only way to ensure that you do not violate that policy is by accurately paraphrasing content from the sources you cite so that the content you add is directly supported by its source.

If you intend to continue writing content on complex topics in neuroscience, you need to pay more attention to the details of the sources you cite and generalize a lot less than you have been in order to ensure that the content you write is accurate; otherwise, I'm very likely going to end up having to revert or heavily revise your additions. If you want to have a broader discussion about this, I'm open to seeking input from WT:NEURO. Seppi333 (Insert 2¢) 22:02, 18 January 2017 (UTC)

Seppi333 (talk · contribs) I am not defensive, nor am I against constructive criticism, however I am against destructive editing. If something is factually incorrect, yes it should be removed, however if something is missing, removing it is not warranted. I am adding back the table with orexinergic projections. The table doesn't imply anything about the uniformity of inputs at all, I don't get why you keep insisting that...Lastly, the articles specifically cite what occurs when the endocannabinoidal and noradrenergic neurons are stimulated, the cause an increase in firing rate, and the articles use excitatory to describe this. Petergstrom (talk) 22:19, 18 January 2017 (UTC)

When you misrepresent a source by stating that a collection of inputs to the VTA/SNc applies to every dopaminergic cell group, yes that absolutely needs to be removed or revised. Once again you've completely missed my point though. The fact that it wasn't comprehensive was only a minor issue. The issue which I covered when I said "most important of all" was relevant to WP:VERIFIABILITY. You and I are going to continue to have problems in the future if you can't simply adhere to that policy. For now, I've greatly limited the scope of the table and fixed the issues I've pointed out. Seppi333 (Insert 2¢) 23:22, 18 January 2017 (UTC)

@Seppi333:

"Overall, NE exerts excitatory control"

Systemic administration of the natural psychoactive cannabinoid delta 9-tetrahydrocannabinol (delta 9-THC) and the synthetic cannabimimetic aminoalkylindole WIN 55,212-2 produced dose-dependent increases in firing rate and burst firing in both neuronal populations. ^[2]

I never said that the collection of inputs apply to dopaminergic nucleus, I have no idea why you interpret it that way.

Petergstrom (talk) 23:59, 18 January 2017 (UTC)

Because you titled the table as Dopaminergic pathway inputs Seppi333 (Insert 2¢) 00:16, 19 January 2017 (UTC)

Also, your ref says: The locus coeruleus and other noradrenergic nuclei in the medulla give rise to norepinephrine (NE)-containing terminals in the VTA/SNc (Phillipson, 1979, Mejias-Aponte et al., 2009). Overall, NE exerts excitatory control over DA neuron activity via activation of α1 adrenergic receptors, causing membrane depolarization, or suppressing the mGluR-induced pause (Grenhoff et al., 1995, Paladini et al., 2001). However, transient activation of α1 adrenergic receptors produces SK-mediated membrane hyperpolarization (Paladini and Williams, 2004). NE can also bind to D2 DA receptors and cause membrane hyperpolarization in DA neurons (Grenhoff et al., 1995, Guiard et al., 2008).

Read the underlined sentence and compare this statement to the bolded sentences. The alpha-1 adrenergic receptor-mediated excitatory/inhibitory effects on these neurons are time-dependent; noradrenergic signaling to D2_Lh is inhibitory. To put that statement in plain English, norepinephrine is not an excitatory neurotransmitter. Seppi333 (Insert 2¢) 00:18, 19 January 2017 (UTC)

Of course, NE is a modulatory neurotransmitter, but the net effect is excitatory. Both of us are(not technically) coming up to 3RR on this point, will add both statements.Petergstrom (talk) 00:30, 19 January 2017 (UTC)

@Petergstrom:The source DOES NOT SAY "the net effect is excitatory". THIS IS YOUR WP:OR. Your source says "Overall, Norepinephrine does one thing; however norepinephrine also does a second thing. It also produces a third effect". The "Overall" does not mean - "the net effect" - it is simply a transition word (e.g., "moreover", "however", "in addition", etc.). Seppi333 (Insert 2¢) 00:36, 19 January 2017 (UTC)

@Seppi333:Actually overall is not a transition word, it is an adjective describing when taking everything into account...the ref says that OVERALL(NET EFFECT) NE excites the VTA, although it can have an inhibitory effect on some neurons.Petergstrom (talk) 01:07, 19 January 2017 (UTC)

Actually overall is not a transition word - apparently, you are wrong. Seppi333 (Insert 2¢) 01:16, 19 January 2017 (UTC)

Wasn't in the list you gave here. Pretty much every transition word there is an adverb, preposition or conjunction. The point is, in summation , or taking into account the net effect of NE, results in it being excitatory. Thats it. No more. The net effect is excitatory. Period. But also, this, is WP:POINTY-redundant and obviously to make a point. Obnoxious not to mention. Petergstrom (talk) 01:22, 19 January 2017 (UTC)

@Petergstrom: The review I've cited directly contradicts the assertion that you're making. I'm assuming this issue is resolved now, so I'm getting off WP for the day. Seppi333 (Insert 2¢) 01:37, 19 January 2017 (UTC)

"Dopamine neurons have axons that run the entire length of the pathway." ^[1] I would like to find a citation for this statement. M4c9s0 (talk) 04:19, 30 May 2021 (UTC)

I am considering adding to this article with information from:

Principles of neural science. Eric R. Kandel, John Koester, Sarah Mack, Steven Siegelbaum (Sixth edition ed.). New York. 2021. ISBN 978-1-259-64223-4. OCLC 1199587061. M4c9s0 (talk) 04:29, 30 May 2021 (UTC)

This article was the subject of a Wiki Education Foundation-supported course assignment, between 23 August 2022 and 7 December 2022. Further details are available on the course page. Student editor(s): Denisej 2 (article contribs). Peer reviewers: Eresha8, Birmaniahern, Hkhan11.

— Assignment last updated by Hkhan11 (talk) 00:43, 2 October 2022 (UTC)

"glutaminergic" should read "glutamatergic". (Yes, the latter and former are enzymatically interconverted, but it's glutamATE that does the neurotransmitting. Glutamine is banked intracellularlyrve for rapid glutamate synthesis aprovidesfor a source of amino groups to synthesize other amino acids when necessary.) 2600:1700:5D52:530:5414:288:706D:47BA (talk) 02:37, 28 January 2024 (UTC)