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June 9

Biology behind Teenage Brain Development

lta –fifteen thousand two hundred twenty four (talk) 07:40, 9 June 2026 (UTC) The following discussion has been closed. Please do not modify it.

For this reasoning, why does the teenager's brain function differently, than the adult brains, and what is behind the biology and psychology? I remember on the example on how the teenager's brain process differently.

For these extra hints, I have learned some information in 2019. According to this books, named "How Psychology Works: The Facts Visually Explained" by DK, explain the concepts and the reasoning of the psychology. In page 22-23, the scanage has revealed that adolescent brains process to utilize information differently than adult brains, and "These differences help to offer a biological explanation for why teenagers can be impulsive, sometimes lack good judgement, and can become overly anxious in social situations." in "What is it?" section. Of course, there are some different approaches about what the body and biological process shape human behavior, and what is determined by individual genetics in some specific areas. I would like to go more in-depth about the evolutionary psychology, including natural selection, individual differences, information processing, and psychological adaptations.

Link to this Book:

• https://dk.com/en-us/products/9781465468611-how-psychology-works

• https://www.goodreads.com/book/show/36747292-how-psychology-works

• https://www.penguinrandomhouse.com/books/600739/how-psychology-works-by-dk/

~2026-33106-46 (talk) 22:02, 3 June 2026 (UTC)

Already at a young age, there is a large variation among children of the same age in how impulsively they act and how risk-averse they are. While adults tend to exercise more self-control than their younger selves, it is methodologically very difficult to determine how much of this is due to greater physiological maturity of the brain and how much can be ascribed to having learned more about the potential consequences of one's actions, whether through actual experience or through reflection.

Myelination of the brain commences before birth and progresses well into adulthood; see Timeline of human brain development. The regions of the prefrontal cortex are the last in which this maturation process reaches its completion. Since this brain region is involved in a wide range of higher-order cognitive functions, including risk processing, and its basic activity is considered to be the orchestration of thoughts and actions in accordance with internal goals, it is plausible that this plays a role in observed age-related behavioural differences. But, as said, the extent to which this physiological aspect explains these differences is very hard to assess.  ​‑‑Lambiam 05:43, 4 June 2026 (UTC)

A lot of synaptic pruning happens during adolescence. I wonder how that impacts brain function. Sean.hoyland (talk) 07:54, 4 June 2026 (UTC)

Youth often behave as if they think they're immortal. That's been true forever. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:04, 4 June 2026 (UTC)

@Baseball Bugs @Lambiam @Sean.hoyland How could this be definitely true forever? I could learn this in a book. ~2026-33106-46 (talk) 22:33, 4 June 2026 (UTC)

References

June 5

Cheap vacuum pump

Can a thing like that be any good? Purpose is evacuating those compression storage bags (plastic bag that you put around pillows and stuff to make them smaller), and similarly with a foam insulated camping pad. I tried a vacuum cleaner and that doesn't generate nearly enough vacuum. But other vac pumps e.g. at Harbor Freight cost a lot more. This would be for occasional use so I'm not too worried about durability as long as it basically works. Also it says 28.3" Hg which is about 0.94 atmosphere (i.e. all but 0.06 atm is removed). That should be plenty for the purpose, right? thx. ~2026-33254-93 (talk) 04:31, 5 June 2026 (UTC)

That pump appears to be air driven. That means you need a decent compressed-air source to drive it. An Amazon search for what you are trying to do, for low cost, gave me lots of cheap electric and hand-operated options: . DMacks (talk) 04:42, 5 June 2026 (UTC)

Thanks and good catch on the compressed air, I better look omre closely. But the devices you linked to say things like "6000 Pa vacuum" which is like 1 psi, comparable to a vacuum cleaner, and I found that using a hand vac (dustbuster style) didn't generate anywhere near enough suction. I guess I could consider a web-dry shop vac as those claim around 40 inches of water lift which is around 2 psi. But I would have thought I needed actual vacuum (say 90% rather than 10%) to really compress the stuff in the bag. I'll try some more tests I guess. (This is OP). ~2026-33680-75 (talk) 20:02, 6 June 2026 (UTC)

I recently used an Amazon-purchased bag+pump combination to reduce the volume of goods (mainly clothes). The electric pump was definitely cheap in price and construction, but managed a satisfactory result in turning a floppy bag into a fairly rigid item that could be stacked on edge without collapsing. But the thing is, this doesn't require a vacuum. All it is doing is removing the air from the bag, assisted by normal atmospheric pressure on the outside. Most of the work is done by the valve, which stops any air removed from returning. All the pump has to do is lower the pressure outside the valve to slightly less than the pressure inside the valve, which (given the bag is not a rigid container) continues to be atmospheric pressure. The result is not a vacuum, but a bag with very little air between the other contents. What that pump could not possibly do is reduce the pressure within a rigid vessel to anywhere close to a vacuum. -- Verbarson  ^talk_edits 21:28, 6 June 2026 (UTC)

When compressing things like clothes. pillows, goosedown items, etc., the limit is when the item pushes back as hard as the plastic is pushing in. Things like folded canvas pretty much resist further squeezing no matter how hard you squeeze them. Foam pillows, on the other hand, keep getting smaller as you add more force.

Another gotcha is this: sometimes "2 psi of vacuum" means "2 PSI away from 0 PSI" and other times it means "2 PSI away from 14.7 PSI". Vacuum pumps and vaccuum cleaners are especially likely to use different definitions. An engineer would say "2 PSI absolute" or "2 PSI delta".

Your best bet to get the lowest absolute pressure in the bag at a reasonable cost is a sous vide pump ( https://www.amazon.com/s?k=sous+vide+pump&s=price-asc-rank ) but be aware that if it is a hand pump you are going to do a lot of pumping and if it is electric it may be slow and you may have to stop partway through to let the pump cool down. --Guy Macon (talk) 21:53, 6 June 2026 (UTC)

Thanks, wow, the sous vide pump is a cool idea. I couldn't find any vacuum spec for the ones I looked at, but someone on reddit linked a video (timestamped yt link) showing something similar getting better than 27 inches Hg (0.9 atm) delta. It looks like a lot of pumping effort, but they're cheap, so I might give one a try. If it's good at compressing the storage bags (yes they will have springy stuff like pillows) and it's useful, then I can spend more on an HVAC style one. I think it's fair enough to read the water lift spec on a wet/dry vacuum cleaner as a delta pressure measurement. Besides the sous vide type I see some for mason jars, that look similar, and pumping out mason jars for stuff like coffee could be handy in its own right. ~2026-33929-47 (talk) 23:19, 8 June 2026 (UTC)

June 7

Taser safety issues

Could a person subjected to a Taser strike develop ventricular fibrillation appear to be unaffected, and continue in whatever activity prompted the firing of the weapon ? Doug butler (talk) 22:28, 7 June 2026 (UTC)

A court tasked to rule on the weapon crime described would have to rely on statements from involved doctor(s), police, the victim and event witnesses. Wikipedia will not speculate on a legal finding or estimate a probability with no evidence. ~2026-21660-55 (talk) 02:03, 8 June 2026 (UTC)

For how long? I seem to recall reading some time ago that if a person's heart stops during physical activity they can carry on for up to 20 seconds before collapsing (due to lack of oxygen reaching the brain): I cannot however recall the source or how reliable it likely was. {The poster formerly known as 87.81 230.195} ~2026-27434-43 (talk) 02:04, 8 June 2026 (UTC)

You are confusing Ventricular fibrillation with Cardiac arrest. Related, but not the same. And arrhythmia, which is what is mentioned on the Taser safety issues page, is different from both. I had cardiac arrest, hitting me in the middle of my WP:RfA and putting me in a coma. And yes, I do think that the stress from the hell we put RfA candidates through contributed to it happening at that particular time. I was literally reading my RfA page when it happened. Since then I have experienced Vtach and Afib, each ending when my Implantable cardioverter defibrillator/pacemaker fired. --Guy Macon (talk) 03:50, 8 June 2026 (UTC)

I was deliberately not specifying the cause of the heart's action stopping, whether due to physiological disorder, electrical interference, or for that matter a bullet or knife. The point was that (assuming my half-remembered fact is true), the cessation of effective heart function need not result in instantaneous collapse. {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 16:05, 8 June 2026 (UTC)

A resolution of this question would by extension to victims of Mme. la Guillotine go far to resolve the question of how they rate the experience. ~2026-21660-55 (talk) 21:48, 8 June 2026 (UTC)

During ventricular fibrillation the heart no longer supplies fresh blood to the brain. Normally, this will cause the patient to lose consciousness within minutes, but cases have been observed of patients remaining conscious. Continuing officer-defying activities for a sustained period is perhaps not entirely impossible, but would be quite unexpected.  ​‑‑Lambiam 09:40, 8 June 2026 (UTC)

Much more likely is police lying and saying that an unconscious person was actively resisting. --Guy Macon (talk) 14:27, 8 June 2026 (UTC)

In the United States, there are about 27,000 arrests per day. Your claim is that it is "more likely" that all of the police involved in all of the arrests are there just to claim an unconscious person was resisting? Or, perhaps, could you be taking a relatively few abnormal situations and claiming that it is the norm because you have a separate narrative to justify? ~2026-16820-81 (talk) 11:24, 9 June 2026 (UTC)

Things can be worse, like in the case of Killing of Daunte Wright, where a cop shot a gun after saying it was a taser. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:04, 9 June 2026 (UTC)

I do not know what occasioned the question, but if police officers tasered a person after the latter suffered ventricular fibrillation, and the police report states that their action was justified in accordance with official instructions because suspect refused to comply, I might be inclined to question the veracity of this statement, regardless of the fraction of legitimate and peaceful arrests.  ​‑‑Lambiam 12:33, 9 June 2026 (UTC)

The story as told above seems to be extremely unlikely, but I can think of two plausible alternative explanations: [1] that whatever source says that they tasered someone already in ventricular fibrillation is wrong or perhaps the source doesn't actually say that. Anyone got a link? Or [2] "refusing to comply" consisted of not following an order such as "put your hands behind your back" or "get out of the vehicle" while unconscious. Not that the latter makes the police look any better. Or does the source say that the cops claim resisting rather than refusing to comply? Anyone got a link? --Guy Macon (talk) 14:54, 9 June 2026 (UTC)

I was thinking of an officer believing their Taser had been ineffective, where in fact it was effective, but in an unexpected direction: sending the heart into an anomalous mode (spasm, VF, whatever). The offender could continue to operate in their antisocial activity for many seconds before unconsciousness set in. The officer might then resort to a more lethal weapon. Doug butler (talk) 13:27, 10 June 2026 (UTC)

June 8

Relations between Scientology and Science

lta –fifteen thousand two hundred twenty four (talk) 07:40, 9 June 2026 (UTC) The following discussion has been closed. Please do not modify it.

How are the relations between Scientology and Science? Are both based of reasoning, evidence, and intelligence? ~2026-33778-68 (talk) 23:45, 8 June 2026 (UTC)

Outright hostile. The latter is rational; the former is a particularly evil cult. The only thing they share is "scien". Clarityfiend (talk) 00:15, 9 June 2026 (UTC)

Maybe similar to alchemy vs. chemistry? ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:33, 9 June 2026 (UTC)

Alchemy gradually turned into chemistry as better experimental methods were developed; see History of chemistry. They are not in rivalrous opposition. A better comparison is astrology vs. astronomy, although it is fair to see astrology as the mother of astronomy, while scientology has contributed zilch to science.  ​‑‑Lambiam 07:08, 9 June 2026 (UTC)

Scientology was founded as a deliberate money-making scam in the 1950s by popular fiction writer L. Ron Hubbard, building on his earlier 'alternative Psychology' invention 'Dianetics'. Both employed pseudo-scientific assertions and the latter a great deal of elaborate psychological manipulation. Certainly no real science stems from Scientology in the way that Chemistry stemmed from Alchemy.

Hubbard seems to have been one of those people who insist on being dishonest even when honesty would be easier and possibly more lucrative. (I have worked for one such person, now dead, perhaps other examples may spring to mind.) In the 1930s and 40s Hubbard was a prolific and at times capable and effective, though not outstanding, adventure-story writer who could have built his talents in that sphere further: instead he chose a different path. Note that the long (and very bad) novels published under his name in the 1980s were almost certainly by other hands, with the possible exception of the first (which if by him was in my personal opinion a tongue-in-cheek parody). {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 02:23, 9 June 2026 (UTC)

Wikipedia covers some of Scientology's pseudoscientific claims at Flag Building#Perceptics. Here is some info on the Super Power building (later renamed the Flag Building) where Scientologists can obtain "Super Powers" such as immunity from all physical ailments, telekenesis, mind control, complete control of mass, energy, space, and time, complete recall of everything that ever happened to them, grandmaster level chess ability, telepathy, etc:

* Inside Scientology's super power building: welcome to the smell wall --The Guardian

* Scientology: Secrets of the Super Power Building --Tony Ortega, published in The Village Voice

* Scientology and oiliness: More renderings from the Super Power Building --Tony Ortega, published in The Village Voice

--Guy Macon (talk) 05:39, 9 June 2026 (UTC)

June 10

Oxidisation states

Which element has the most oxidation states? ~2026-34127-16 (talk) 00:01, 10 June 2026 (UTC)

Please make at least an effort to find the answer before asking it here. Googling "Which element has the most oxidation states" brings up the Wikipedia page Oxidation state which clearly shows that Iridium has the highest number (13). --Guy Macon (talk) 05:37, 10 June 2026 (UTC)

It’s not Magnesium (7 states)? ~2026-34127-16 (talk) 06:31, 10 June 2026 (UTC)

You may be thinking of manganese there with 9. Magnesium has 3 states in the table. Gallium is listed with 9. Graeme Bartlett (talk) 07:53, 10 June 2026 (UTC)

I count 11 states for manganese, 3 for Magnesium, and 13 for Iridium. --Guy Macon (talk) 14:50, 10 June 2026 (UTC)

A lot of entries in the table are pretty exotic, to be fair. Double sharp (talk) 16:37, 10 June 2026 (UTC)

Criminals and lead poisoning

In the United States and elsewhere, are those who are inmates or convicted criminals checked or researched for the possibility of lead poisoning?Rich (talk) 05:16, 10 June 2026 (UTC)

Why would they be? ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:37, 10 June 2026 (UTC)

Possibly a confusion between Lead poisoning and the Lead–crime hypothesis. The latter is statistical. There are many such statistical correlations. For example, males commit approximately 88% to 90% of all murders where the gender of the perpetrator is known. Also 35% to 38% of murderers are between 18 and 24 years old, compared to 7% to 10% for ages 40 to 49. The statistics tell the police nothing about whether an individual has committed a crime. --Guy Macon (talk) 05:52, 10 June 2026 (UTC)

I don't see what the confusion would be. I just asked if this is something that is done. Rich (talk) 09:06, 10 June 2026 (UTC)

...and I answered Baseball Bugs question, "Why would they be?" Which you didn't answer. What do you imaging the police would do with that information? They already have information (age and gender) which has a far larger effect, and (rightly) do nothing with it. --Guy Macon (talk) 14:37, 10 June 2026 (UTC)

I took what you said all wrong, sorry.Rich (talk) 08:37, 12 June 2026 (UTC)

Even supposing there's no good reason they would be, I just asked if it was done. Anyway criminologists might want to know what the results would be.Rich (talk) 09:16, 10 June 2026 (UTC)

No. It isn't done. Besides the obvious fact that cops don't gather data to help criminologists unless the criminologists pay them to do so, it would be a clear violation of the US constitution to take blood samples without probable cause. --Guy Macon (talk) 14:37, 10 June 2026 (UTC)

Some of them might consent.Rich (talk) 03:11, 11 June 2026 (UTC)

I don't see that as an obvious fact at all. I don't think it's a fact. You should research before you answer.Rich (talk) 03:18, 11 June 2026 (UTC)

Who said anything about cops gathering data? --jpgordon^{𝄢𝄆𝄐𝄇} 23:22, 11 June 2026 (UTC)

See also Correlation does not imply causation. Shantavira|^{feed me} 06:39, 10 June 2026 (UTC)

I never said it did.And I never asked about correlation, and I never asked about causation. Rich (talk) 09:06, 10 June 2026 (UTC)

What triggered your question? ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:20, 10 June 2026 (UTC)

The answer is yes, there have been numerous studies addressing the issue; see this Google Scholar search. Alansplodge (talk) 11:39, 10 June 2026 (UTC)

thank you for the direct answer!Rich (talk) 05:42, 12 June 2026 (UTC)

There's some very good studies showing there almost certainly is a link between lead poisoning from cars and crime. However I don't really see how a study of criminals would help, we already know poor neighbourhoods are more exposed to car fumes and criminals tend to come more from poor neighbourhoods. You'd need a lot more in there before you could produce a decent study showing anything more. NadVolum (talk) 11:56, 10 June 2026 (UTC)

But since the sale of leaded gasolene for ordinary cars was banned in the USA in 1996 (after being phased out for some years previously), this should be a declining issue. Alansplodge (talk) 12:46, 10 June 2026 (UTC)

And it is, in fact the consistent time scale because different places banned it at different times is a strong indicator of the effect. NadVolum (talk) 13:31, 10 June 2026 (UTC)

Everyone is trying to put words in my mouth. Rich (talk) 03:12, 11 June 2026 (UTC)

Are you opposed on principle to research?Rich (talk) 03:15, 11 June 2026 (UTC)

Your behavior is coming dangerously close to violating WP:NPA, and it is starting to look like you didn't come to the reference desk with a good faith question, but rather to push a particular POV. You haven't reached the point where you should be reported for WP:NOTHERE, but that's the way it appears thjat you are going. Please stop this behavior now. --Guy Macon (talk) 16:09, 11 June 2026 (UTC)

@Guy, I think you need to disengage. If anyone's behaviour is out of line, it is yours. The OP clearly specified they're asking whether convicts get tested for lead levels. You seem to have confused "convict" with "suspect" and based your answers around that misapprehension. I can't formulate another reason why you keep invoking the role of the police, when they would not be involved in such testing in any way. Matt Deres (talk) 17:52, 11 June 2026 (UTC)

Why would inmates or convicts be tested for lead poisoning? What would be the point? ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:13, 11 June 2026 (UTC)

A conjecture: if a convict/inmate learned that they had been affected by lead exposure that contributed in some way to their criminal behaviour (rather than their just being 'a bad person'), it might help their psychological resolve to rehabilitate. {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 15:12, 11 June 2026 (UTC)

A clever defense attorney might be interested. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:43, 11 June 2026 (UTC)

Indeed they would. If you have been arrested, your defense attorney is your friend and will use anything they can -- including the results of a blood test -- to help you. The police are not your friends. They will use it if it hurts you and ignore it if it helps you. --Guy Macon (talk) 16:09, 11 June 2026 (UTC)

Police officers are not social workers or doctors. They have an important and vital job, but "helping your psychological resolve to rehabilitate" isn't part of it. Nor do interactions with the police give you the legal protection of your medical privacy that you get when talking to social workers or doctors.

If you are really interested in learning about whether you should give information to a police officer, I highly recommend joining the 21 million people who have watched this video: --Guy Macon (talk) 16:09, 11 June 2026 (UTC)

Neither the OP nor any other poster here has said anything about "giving information to a police office", or about involving police officers in any way in a putative study of lead pollution's effects on convicted criminals' behaviour individually or collectively.

Drop your stick and back away from the deceased equine that you yourself dragged in here.

Maybe also take on board that worldwide, police training and police behaviour differs from country to country. 95% of the World's population and its police officers are not American. {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 01:27, 12 June 2026 (UTC)

I got overly defensive, for which I'm sorry!Rich (talk) 05:56, 12 June 2026 (UTC)

You were attacked, IMO for no good reason.  ​‑‑Lambiam 08:50, 12 June 2026 (UTC)

It's to Guy's credit that he is passionate about civil rights...I felt you unfairly attacked my pollution question as mistaken and didn't admit your own mistake, then you later said I had some kind of beef with you.Rich (talk) 13:13, 12 June 2026 (UTC)

Meanwhile, you still haven't answered my original question. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:20, 12 June 2026 (UTC)

Scientific knowledge is in general good to have. Scientific knowledge about criminology can help public policies that tend to prevent criminality and can help criminals reform, and in this case might help victims of crimes sometimes forgive the perpetrators.Rich (talk) 13:08, 12 June 2026 (UTC)

Maybe. Or it could be used as an excuse by perps. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:15, 12 June 2026 (UTC)

Your many questions about why I want to know made, and make, me wonder if you value scientific research.Rich (talk) Rich (talk) 13:25, 12 June 2026 (UTC)

your many questions about why I want to know made, and still make, me wonder if you value scientific research, or ar even opposed to scientific research on principle.Rich (talk) 13:28, 12 June 2026 (UTC)

I agree with research. I don't always agree with how it's used. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:47, 12 June 2026 (UTC)

Just gathering statistics in general without a clear target can be very useful and I can see there possibly being statistics about lead in blood for prisoners being around from something like that - but as I said I don't think it would help show much about such a link. For a directed research topic one needs a clear idea of how the hypothesis would be shown or not. Ingenious studies have clearly shown a link, but they have gone about it quite differently. NadVolum (talk) 16:05, 12 June 2026 (UTC)

This review gives you an idea of the various kinds of observational studies that have been carried out. Sean.hoyland (talk) 17:08, 12 June 2026 (UTC)

I've always wondered about that lead pipe... Martinevans123 (talk) 17:39, 12 June 2026 (UTC)

Yes, it was quite chewy. Also worked well as a tiny pencil to make notes in your small unventilated bedroom about things like your mercury collection from broken thermometers or for playing with molten solder. Sean.hoyland (talk) 03:27, 13 June 2026 (UTC)

June 11

Louth and Korolev crater locations on Mars

To help readers of Korolev (Martian crater) and Louth (crater) get an idea of where they are located, can someone please point out the craters on a full-planet photo of Mars? Thanks, cmɢʟee τaʟκ (please add {{ping|cmglee}} to your reply) 11:56, 11 June 2026 (UTC)

If you click on the coordinates in the info box you get a map of Mars with the crated marked as a yellow dot. --Wrongfilter (talk) 13:24, 11 June 2026 (UTC)