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A wonderful essay exposing all the garbage produced by lay-folks who make money writing books about the suppposed truth of brain function as shown by fMRI's. -
"Paul Fletcher, professor of health neuroscience at the University of Cambridge, says that he gets "exasperated" by much popular coverage of neuroimaging research, which assumes that "activity in a brain region is the answer to some profound question about psychological processes. This is very hard to justify given how little we currently know about what different regions of the brain actually do." Too often, he tells me in an email correspondence, a popular writer will "opt for some sort of neuro-flapdoodle in which a highly simplistic and questionable point is accompanied by a suitably grand-sounding neural term and thus acquires a weightiness that it really doesn't deserve. In my view, this is no different to some mountebank selling quacksalve by talking about the physics of water molecules' memories, or a beautician talking about action liposomes."
 
Shades of grey
 
The human brain, it is said, is the most complex object in the known universe. That a part of it "lights up" on an fMRI scan does not mean the rest is inactive; nor is it obvious what any such lighting-up indicates; nor is it straightforward to infer general lessons about life from experiments conducted under highly artificial conditions. Nor do we have the faintest clue about the biggest mystery of all ... how does a lump of wet grey matter produce the conscious experience you are having right now, reading this paragraph? How come the brain gives rise to the mind? No one knows."-http://www.newstatesman.com/culture/books/2012/09/your-brain-pseudoscience

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More truth: the neuroscience studies are small with little statistical validity:-http://blogs.scientificamerican.com/talking-back/2013/04/10/new-study-neuroscience-research-gets-an-f-for-reliability/?WT_mc_id=SA_DD_20130410

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An example of the garbage being published. Only 20 people and pain thresholds are known to be very different in different people.-http://news.sciencemag.org/sciencenow/2013/04/brain-signature-reveals-our-leve.html?ref=hp

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A good cautionary column.The brain is not the mind!-http://www.nytimes.com/2013/06/18/opinion/brooks-beyond-the-brain.html?nl=todaysheadlines&emc=edit_th_20130618&_r=4&goback=%2Egde_3008673_member_250855393&

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Machine produced accuracy from 60 to 90%. DNA is 99.9%; fingerprints 100%-The usual poppycock:-http://www.sciencedaily.com/releases/2013/06/130619195137.htm

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This article argues that the backlash against overhyped results could throw out the baby with the bathwater. But tries to conflate mind and brain. Scans do not explain conscious thought:-http://www.newyorker.com/online/blogs/elements/2013/06/the-problem-with-the-neuroscience-backlash.html

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http://www.scientificamerican.com/article.cfm?id=mind-reading-technology-speeds-ahead

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Not worth much yet:-http://www.newscientist.com/article/mg22029390.600-hidden-depths-brain-science-is-drowning-in-uncertainty.html?full=true#.VLWxFWA5C1s-"After the furore died down, many fMRI researchers realised that the critiques were essentially right. Voodoo correlations and double-dipping appear to be less common now, and the idea that you can map complex personality traits to a few specific regions like the amygdalae is increasingly considered to be "a pipe dream", says cognitive neuroscientist Tal Yarkoni, also at the University of Texas at Austin. Personality traits are now thought to be associated "with lots of different brain regions interacting in complex ways", he says.-"But as researchers patched up those holes in their methods, other equally serious concerns began to emerge. Last year, for instance, a jaw-dropping study from the University of Michigan demonstrated that an fMRI experiment could be analysed in nearly 7000 ways - and the results could vary hugely. With so much flexibility, neuroimagers can unintentionally (or indeed deliberately) analyse their experiments in a way that yields the most favourable results. One tongue-in-cheek report showed that even a dead salmon's brain could appear to be "thinking" inside a scanner if the wrong techniques were used."

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While I would agree that there is much hyperbolae in some fMRI studies, but I would argue videos like this show there also a great deal of promise in this type of study.
https://www.youtube.com/watch?v=nsjDnYxJ0bo-And bear in mind all this is simply a proxy for blood flow in the brain.

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> Rom; And bear in mind all this is simply a proxy for blood flow in the brain.-I've pointed this out all along. How many steps removed from reality? the brain is too complex to conclude that blood flow studies tell us much.

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> > Rom; And bear in mind all this is simply a proxy for blood flow in the brain.
> 
> I've pointed this out all along. How many steps removed from reality? the brain is too complex to conclude that blood flow studies tell us much.-And yet we can get surprisingly good images from the blood flow?

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> > > Rom; And bear in mind all this is simply a proxy for blood flow in the brain.
> > 
> > David: I've pointed this out all along. How many steps removed from reality? the brain is too complex to conclude that blood flow studies tell us much.
> 
>Rom: And yet we can get surprisingly good images from the blood flow?-It is like apples and oranges. We need to know neuron function and connections, and we are looking at fuel supply. Can't infer very much!

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Another reminder of what is measured, blood flow and oxygen consumption, nothing more:-http://www.the-scientist.com/?articles.view/articleNo/45366/title/Demystifying-BOLD-fMRI-Data/&utm_campaign=NEWSLETTER_TS_The-Scientist-Daily_2016&utm_source=hs_email&utm_medium=email&utm_content=26383650&_hsenc=p2ANqtz--h6TGTF6isCR92q5ugiju74xIdRiSTuZaZ3IOhs8Ie2etxK9VEykXHmtzwxQ2-s21hCtG87fjLVy4aayP0D5iV15W6lg&_hsmi=26383651/-'What we do know, of course, is what MRI measures, said Robert Turner, director emeritus of the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, Germany. MRI measures the magnetization of hydrogen protons in water molecules excited by pulses of radio waves that lead their spins to temporarily align. Over the next few tens of milliseconds, Turner noted, their orientations fan out again, and the magnetization we measure will quickly decrease.-'But what can this tell us about brain activity?-"When hemoglobinsthe iron-rich oxygen-carrying proteins in our bloodrun out of oxygen, Turner explained, they become paramagnetic, disturbing the local magnetic field. This makes the protons spin out of phase more rapidly. One might think this means BOLD fMRI highlights oxygen consumption by active neurons, but in reality, such activity is rarely measured.-"What BOLD does reveal is what usually happens next: fresh blood rushes into the area, flushing out paramagnetic deoxyhemoglobin and replacing it with new, oxygenated hemoglobin. Since this does not interfere with the proton spins, the result is a larger fMRI signal. So BOLD fMRI reflects a combination of changes in blood flow and oxygen consumption within the brainnot neuronal activity itself.-This means that if BOLD shows you a large blob of activity, that doesn't necessarily mean that all the neurons in that region are spiking, said David Attwell of University College London, one of the meeting's organizers. So what we really need to know is how neurons are influencing bloodflow.-***-
"But in some brains, BOLD may not work at all, Hillman cautioned. In the developing brain of young animals, for example, we find that BOLD activity is very unusual, she said. Initially, the bloodflow response doesn't seem to be attuned to neural activity at all, so fMRI may be as good as blind.-"Diseased brains can also skew results. Pathology may affect the BOLD signal in the absence of any changes in neurons themselves, said Bojana Stefanovic of Toronto's Sunnybrook Research Institute. In patients who suffered a stroke, for example, the amount of water may be reduced where cells have died, and increased by oedema in some of the surrounding tissues. The brain's bloodflow may also be altered by disruptions to the vasculature, for example, or the formation of scar tissue.-"The best way to deal with this depends on the research question, Stefanovic told The Scientist. There's this idea that if we can link BOLD to neuronal activitythat would be nirvana, she said. Clinicians, however, are looking for measures with a clear link to symptoms. And, fortunately, there is no shortage of disease effects BOLD can sense.'-***-'Surprisingly, we found that while BOLD responds to expected reward and actual outcome separately, the dopamine response integrates them into one better or worse' signal.'"-Comment: Still an indirect measurement of areas of the brain, nothing more.

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This paper is a review of the statistical results that come from the software that analyzes scans. Essentially not reliable:-http://www.theregister.co.uk/2016/07/03/mri_software_bugs_could_upend_years_of_research/-"A whole pile of this is how your brain looks like fMRI-based science has been potentially invalidated because someone finally got around to checking the data.-"The problem is simple: to get from a high-resolution magnetic resonance imaging scan of the brain to a scientific conclusion, the brain is divided into tiny voxels. Software, rather than humans, then scans the voxels looking for clusters.-"When you see a claim that scientists know when you're about to move an arm: these images prove it, they're interpreting what they're told by the statistical software.-"Now, boffins from Sweden and the UK have cast doubt on the quality of the science, because of problems with the statistical software: it produces way too many false positives.-"In this paper at PNAS, they write: the most common software packages for fMRI analysis (SPM, FSL, AFNI) can result in false-positive rates of up to 70%. These results question the validity of some 40,000 fMRI studies and may have a large impact on the interpretation of neuroimaging results.-"For example, a bug that's been sitting in a package called 3dClustSim for 15 years, fixed in May 2015, produced bad results (3dClustSim is part of the AFNI suite; the others are SPM and FSL).-"That's not a gentle nudge that some results might be overstated: it's more like making a bonfire of thousands of scientific papers.-"Further: Our results suggest that the principal cause of the invalid cluster inferences is spatial autocorrelation functions that do not follow the assumed Gaussian shape.-From the paper itself:-http://www.pnas.org/content/113/28/7900.full-"Significance-Functional MRI (fMRI) is 25 years old, yet surprisingly its most common statistical methods have not been validated using real data. Here, we used resting-state fMRI data from 499 healthy controls to conduct 3 million task group analyses. Using this null data with different experimental designs, we estimate the incidence of significant results. In theory, we should find 5% false positives (for a significance threshold of 5%), but instead we found that the most common software packages for fMRI analysis (SPM, FSL, AFNI) can result in false-positive rates of up to 70%. These results question the validity of some 40,000 fMRI studies and may have a large impact on the interpretation of neuroimaging results." -Comment: I'm not surprised. The fMRI is a shorthand trick to look at areas of the brain that light up with thought activity. All this does is give us a hint of which areas of the most complex organ in the universe are assigned to do the work, nothing more.

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Another version of the discovery that some fMRI is not that statistically reliable:-https://www.newscientist.com/article/2097734-thousands-of-fmri-brain-studies-in-doubt-due-to-software-flaws/-"It's another blow for neuroscience. The discovery of major software flaws could render thousands of fMRI brain studies inaccurate.-***-"Anders Eklund and Hans Knutsson at Linköping University in Sweden and Thomas Nichols at the University of Warwick, UK, calculated this by analysing brain data from a collaborative open fMRI project called 1000 Functional Connectomes. Most fMRI statistical methods have been developed using simulated data, but in this case the team was able to use real brain information to validate the techniques for identifying significant patterns of activity in fMRI scans.-"This work enabled the researchers to confirm that a statistical software flaw they first identified in 2012 truly does produce false positives at an alarmingly high rate. Four years ago, they were not taken very seriously because their work at that time was based on data from a single person.
 
"Now we know that this is a very real problem indeed. Although the software error has now been corrected, potentially thousands of fMRI studies are in doubt.-***-"According to Ekland, it is difficult to determine which studies have been affected by the spatial autocorrelation flaw because raw data from past studies is rarely available.-"Nichols estimates that around one in 10 fMRI studies may be affected. This is somewhat lower than the full 15 years of brain research that some publications have suggested are now called into question.-"However, when you take into account that, on top of the software flaw, a further 40 per cent of this type of study may be compromised by researchers failing to apply the right corrections in the first place, this hints that many studies indeed may have reported false positive results.-"The types of study most likely to be affected are those that are usually reported with headlines along the lines of X causes part Y of your brain to light up, or This is your brain on drug Z. Those that show relatively weak statistical associations are the likeliest to be inaccurate - whereas studies reporting strongly significant findings may ultimately still be sound.-***-"But not all fMRI researchers are worried. Jens Foell at Florida State University in Tallahassee likens fMRI to using a blurry magnifying glass to look at the most complex object in the universe. As a consequence, he says, we should always be sceptical of fMRI studies with results that have only borderline statistical significance.-"In light of this growing evidence of the unreliability of some fMRI research, it is more important than ever to treat findings with caution. There is a large body of psychological evidence that shows people are particularly easily swayed by neuroscience. But although neuroscience is an important field, it is a young one that relies on inherently fuzzy data. Psychological studies that measure behaviour and actions directly may often be more useful, relevant and reliable.-'What I expect the fMRI research community to do now is neither to worry nor to be surprised, but to engage in rigorous discussion, says Foell."-Comment: Caution, do not over-interpret.

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From a expert scientist:

http://nautil.us/issue/60/searches/why-happiness-is-hard-to-findin-the-brain?utm_source...

"That’s not really how fMRI works, or how it should work. Back when fMRI was developed, back in the ’90s, what we call the “bad old days” of neuroimaging, there was a lot of what we called “Blobology”: putting people in scanners and hunting around for “blobs” of activity in the brain.

"One of my favorite examples of this is from one of the very first conferences I went to; there was a study being presented called “The fMRI of Chess vs Rest.” Basically, you had people lying in a scanner, either playing chess, or doing nothing. The whole brain was active, but in different ways for the different scenarios, and in the chess scenario certain brain regions would show up as “more” active. From this, they then claimed these regions are responsible for the processes involved in chess. There was so much inverse inference applied: This part is active, and we do these things in chess, so that must be what those areas are for. It’s working backward. It’s viewing the brain like a car engine; the idea that each brain region must do one thing and one thing only.

"This approach leads to these wrong conclusions; you see activity in a brain region and assign it a specific function. But it’s completely wrong. Multiple functions are subsumed by multiple areas, which are handled by cognitive networks. It’s very complicated. That’s a problem with neuroimaging generally; it goes up a notch further when you’re dealing with anything subjective, like happiness.

***

"It turned out Professor Chambers is a very keen and active individual when it comes to highlighting the issues and problems that afflict modern neuroimaging studies, and psychology in general. He’s even written a book, The Seven Deadly Sins of Psychology,1 all about how modern psychology could and should be improved.

"There are several important issues about fMRI that clarified just how hard it would be for me to use it to set up an experiment to find happiness. Firstly, as stated, it’s expensive. So studies that utilize it tend to be relatively small, using a limited number of subjects. This is an issue, because the fewer subjects you use, the less certain you can be that your results are significant. The greater the number of subjects used, the greater the “statistical power”2 of any results, and the more confident you can be that they’re valid.

***

"The data produced by fMRI aren’t nearly as clear as mainstream reports suggest. Firstly, we talk about which parts of the brain are “active” during a study, but as Professor Chambers pointed out, “This is effectively nonsense. All parts of the brain are active, all the time. That’s how the brain works. The question is how much more active are these certain regions, and is it significantly more active than it usually is.

***

“'fMRI has a huge what we call ‘researcher degrees of freedom’ problem. People often don’t decide how they’re going to analyze their data, or sometimes even which question they’re going to ask, until after they’ve run their study. And they go ahead, and they explore, and they have this ‘garden of forking paths’ problem, where in even the simplest of fMRI studies there are thousands of analytical decisions to make, each one of which will slightly change the outcome they get. So what researchers will do is mine their data at the end to find a result which is useful.”

"This comes about because there are many different ways to analyze complex data, and one combination of approaches may provide a useful result, where others wouldn’t. It may sound dishonest, somewhat like firing a machine gun at a wall then drawing a target around where the most bullet holes are clustered and claiming to be a good shot. It’s not that bad, but it’s heading that way. But then when your career and success depends on hitting the target and this option is available, why wouldn’t you do it?"

Comment: same thoughts as usual. The fMRI follows muscle movement and other application areas fairly easily but thought may be in frontal areas and is influenced by other areas controlling emotions, which are harder to define. Gives us some info on how the s/s/c interfaces to use the brain networks.

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QUOTE: This part is active, and we do these things in chess, so that must be what those areas are for. It’s working backward. It’s viewing the brain like a car engine; the idea that each brain region must do one thing and one thing only.
"This approach leads to these wrong conclusions; you see activity in a brain region and assign it a specific function. But it’s completely wrong. Multiple functions are subsumed by multiple areas, which are handled by cognitive networks. It’s very complicated.

DAVID’s comment: […] Gives us some info on how the s/s/c interfaces to use the brain networks.

Three cheers. I hate the compartmentalization theory. The brain is a community of cell communities which all work together. I’d like to know more about the “cognitive networks”. Usual question: does the s/s/c arise out of these networks, or is it part of your God’s consciousness?

Under “Observed memory formation”:

DAVID’s comment: we have evolved from lower animals and they are conscious, but without our consciousness. Our s/s/c has followed these routes of brain connections as we have developed more thinking mind areas. It just shows how the s/s/c interlocks with brain networks.

I would love to know where you draw the line between conscious “lower animals” and robotic, pre-preprogrammed “lower animals”. At the moment we have mice as conscious and ants and weaverbirds as robots. There is no question that the s/s/c interlocks with brain networks. Same question as above: does the s/s/c have its source in the brain networks, or did your God “give it us” and it will pop out again when the brain is dead?

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QUOTE: This part is active, and we do these things in chess, so that must be what those areas are for. It’s working backward. It’s viewing the brain like a car engine; the idea that each brain region must do one thing and one thing only.
"This approach leads to these wrong conclusions; you see activity in a brain region and assign it a specific function. But it’s completely wrong. Multiple functions are subsumed by multiple areas, which are handled by cognitive networks. It’s very complicated.

DAVID’s comment: […] Gives us some info on how the s/s/c interfaces to use the brain networks.

dhw: Three cheers. I hate the compartmentalization theory. The brain is a community of cell communities which all work together. I’d like to know more about the “cognitive networks”. Usual question: does the s/s/c arise out of these networks, or is it part of your God’s consciousness?

I view the s/s/c as having to use these cognitive networks. I think iti spart of God's consciousness

dhw: Under “Observed memory formation”:

DAVID’s comment: we have evolved from lower animals and they are conscious, but without our consciousness. Our s/s/c has followed these routes of brain connections as we have developed more thinking mind areas. It just shows how the s/s/c interlocks with brain networks.

dhw: I would love to know where you draw the line between conscious “lower animals” and robotic, pre-preprogrammed “lower animals”. At the moment we have mice as conscious and ants and weaverbirds as robots. There is no question that the s/s/c interlocks with brain networks. Same question as above: does the s/s/c have its source in the brain networks, or did your God “give it us” and it will pop out again when the brain is dead?

Instincts exist at all levels of development, but I am sure ants, weaverbirds and mice are conscious. I view some instincts as learned behavior when they are simple and some as given instincts by God when they are too complex for simple adaptation. Of course God gave us consciousness which survives brain death.

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dhw: Three cheers. I hate the compartmentalization theory. The brain is a community of cell communities which all work together. I’d like to know more about the “cognitive networks”. Usual question: does the s/s/c arise out of these networks, or is it part of your God’s consciousness?

DAVID: I view the s/s/c as having to use these cognitive networks. I think it is part of God's consciousness.

Or of course it may be that the s/s/c emerges from the interplay between the cognitive networks. That is the starting-point of the dichotomy we have been discussing for so long.

Under “Observed memory formation”:

DAVID’s comment: we have evolved from lower animals and they are conscious, but without our consciousness. Our s/s/c has followed these routes of brain connections as we have developed more thinking mind areas. It just shows how the s/s/c interlocks with brain networks.

dhw: I would love to know where you draw the line between conscious “lower animals” and robotic, pre-preprogrammed “lower animals”. At the moment we have mice as conscious and ants and weaverbirds as robots. There is no question that the s/s/c interlocks with brain networks. Same question as above: does the s/s/c have its source in the brain networks, or did your God “give it us” and it will pop out again when the brain is dead?

DAVID: Instincts exist at all levels of development, but I am sure ants, weaverbirds and mice are conscious. I view some instincts as learned behavior when they are simple and some as given instincts by God when they are too complex for simple adaptation. Of course God gave us consciousness which survives brain death.

You always leave out the all-important origin of what you call instincts. The complexities of the ant hill and the weaverbird’s nest can only have originated through the work of combined intelligences in the one, and individual intelligence in the other (unless a flock of weavers got together to invent the knots). The explanation you give is that in both cases, the intelligence(s) came directly from your God either programming the first living cells with ALL the complex innovations 3.8 billion years ago, or dabbling personally to insert a nest-building programme which all forthcoming ants/weavers would be compelled to switch on. Ah, if only he’d thought of inventing a programme that would enable all organisms to work it out for themselves! Or maybe he did...

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dhw: Three cheers. I hate the compartmentalization theory. The brain is a community of cell communities which all work together. I’d like to know more about the “cognitive networks”. Usual question: does the s/s/c arise out of these networks, or is it part of your God’s consciousness?

DAVID: I view the s/s/c as having to use these cognitive networks. I think it is part of God's consciousness.

dhw: Or of course it may be that the s/s/c emerges from the interplay between the cognitive networks. That is the starting-point of the dichotomy we have been discussing for so long.

Under “Observed memory formation”:

DAVID’s comment: we have evolved from lower animals and they are conscious, but without our consciousness. Our s/s/c has followed these routes of brain connections as we have developed more thinking mind areas. It just shows how the s/s/c interlocks with brain networks.

dhw: I would love to know where you draw the line between conscious “lower animals” and robotic, pre-preprogrammed “lower animals”. At the moment we have mice as conscious and ants and weaverbirds as robots. There is no question that the s/s/c interlocks with brain networks. Same question as above: does the s/s/c have its source in the brain networks, or did your God “give it us” and it will pop out again when the brain is dead?

DAVID: Instincts exist at all levels of development, but I am sure ants, weaverbirds and mice are conscious. I view some instincts as learned behavior when they are simple and some as given instincts by God when they are too complex for simple adaptation. Of course God gave us consciousness which survives brain death.

dhw: You always leave out the all-important origin of what you call instincts. The complexities of the ant hill and the weaverbird’s nest can only have originated through the work of combined intelligences in the one, and individual intelligence in the other (unless a flock of weavers got together to invent the knots). The explanation you give is that in both cases, the intelligence(s) came directly from your God either programming the first living cells with ALL the complex innovations 3.8 billion years ago, or dabbling personally to insert a nest-building programme which all forthcoming ants/weavers would be compelled to switch on. Ah, if only he’d thought of inventing a programme that would enable all organisms to work it out for themselves! Or maybe he did...

We see the results of organisms activities, but must interpret them, as we cannot know how they were devolved. We both have our separate theories. God may have given the organisms the ability you desire them to have. I've admitted that, but have always insisted He supplied guidelines, since His purpose in evolution is to eventually produce us.

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Calcium and neuron signals:

https://www.sciencedaily.com/releases/2021/07/210721190113.htm

Unlike the rest of the body, there is not enough real estate in the brain for stored energy. Instead, the brain relies on the hundreds of miles of blood vessels within it to supply fresh energy via the blood. Yet, how the brain expresses a need for more energy during increased activity and then directs its blood supply to specific hot spots was, until now, poorly understood.

Now, University of Maryland School of Medicine and University of Vermont researchers have shown how the brain communicates to blood vessels when in need of energy, and how these blood vessels respond by relaxing or constricting to direct blood flow to specific brain regions.

"...the researchers say that understanding how the brain directs energy to itself in intricate detail can help determine what goes wrong in conditions like Alzheimer's disease and dementia, where faulty blood flow is a predictor for cognitive impairment. If the brain does not get blood to where it needs it when it needs it, the neurons become stressed, and over time they deteriorate ultimately leading to cognitive decline and memory problems.

***

"They found that when neurons fire electrical signals, they cause an increase in calcium in the cells lining the blood vessels. Then enzymes detect this calcium and direct the cells to make nitric oxide. Nitric oxide is a hormone (and a gas) that causes muscle-like cells around blood vessels to relax, which then widens the vessels allowing more blood to flow in.

"'Capillaries were traditionally thought as simple conduits for red blood cells, and the barrier between the blood and brain," says co-senior author Mark T. Nelson, PhD, University of Vermont Distinguished Professor and Chair of Pharmacology. "Here, we revealed an unknown universe of calcium signaling in capillaries, and much like traffic lights, these calcium signals direct vital nutrients to nearby active neurons.'"

Comment: This is amazingly complex system. The mammalian, not storing energy, must supply it by a precise control over blood supply of oxygen and nutrients to allow responses and thought. Too complex to be designed by chance mutations. Only a designer fits.

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