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Scientists stumble across new organs in the human head
New cancer-scanning technology reveals a previously unknown detail of human anatomy.
- Scientists using new scanning technology and hunting for prostate tumors get a surprise.
- Behind the nasopharynx is a set of salivary glands that no one knew about.
- Finding the glands may allow for more complication-free radiation therapies.
The research began about as far away from where it ended up as possible. Doctors were using PSMA PET/CT scans to assess whether patients' prostate cancer had spread to other parts of their bodies. In addition to being a promising new technology for detecting tumors, PSMA PET/CT scans also happen to be good at imaging salivary glands. Still, radiation oncologist Wouter Vogel and oral and maxillofacial surgeon Matthijs Valstar didn't know quite what to make of two lit-up areas behind the nasopharynx that looked an awful lot like big, undiscovered salivary glands.
Since finding a whole new organ in the human body at this point is unexpected, to say the least, the researchers re-examined the PSMA PET/CT from all 100 patients in their study, plus two cadavers. Every one of them had the same thing.
Says senior author of the study Vogel, "As far as we knew, the only salivary or mucous glands in the nasopharynx are microscopically small, and up to 1000 are evenly spread out throughout the mucosa. So, imagine our surprise when we found these."
The study's lead author Valstar adds, "The two new areas that lit up turned out to have other characteristics of salivary glands as well."
Vogel and Valstar work for the Netherlands Cancer Institute, specializing in the effects of radiation therapy on the head and neck. Their discovery may help technicians alleviate some common radiation side effects now that they know to avoid the new salivary organs, which they've named the "tubarial salivary glands."
The research is published in Radiotherapy & Oncology.
PSMA PET/CT technology
PSMA PET/CT is a new combination of PET scans and CT scans that is believed to offer a more reliable means of locating prostate cancer metastasis. A study published last spring suggests it may be the most accurate way to diagnose prostate cancer metastasis than any method previously available.
Prior to PSMA PET/CT, the primary way to look for metastatic prostate cancer was to image the body using x-ray-based CT scans and to perform bone scans, since bone is where prostate cancer often spreads. CT scans, however, often miss small tumors, and bone scans can generate false positives as a result of other damage or abnormalities that have nothing to do with prostate cancer.
PSMA PET/CT scans track the travels of an intravenously administered radioactive glucose tracer throughout the body. For hunting down prostate cancer, this tracer contains a molecule that binds to the PSMA protein that's present in large amounts in prostate tumors. The molecule is linked to a radioisotope, gallium-68 (Ga-68).
In last spring's research, PSAM PET/CT was shown to be 27 percent more accurate than previous methods at finding metastases (92 percent accuracy as opposed to 65 percent). In addition, it was found to be much less likely to produce false positives, and it was particularly good at detecting tumors far removed from the prostate.
A good kind of avoidance behavior
"Radiation therapy can damage the salivary glands," says Vogel, "which may lead to complications. Patients may have trouble eating, swallowing, or speaking, which can be a real burden."
The researchers looked back through the cases of 723 patients who had undergone radiation treatment, interested in seeing if inadvertent radiation of the tubarial glands was associated with the complications experienced by the patients. It turned out that this was the case: In cases where more radiation had been delivered to this area, patients did indeed report more in the way of complications of the type one would expect when salivary glands are radiated.
Now that we know the tubarial salivary glands exist, therapists can stay out of their way. Vogel says, "For most patients, it should technically be possible to avoid delivering radiation to this newly discovered location of the salivary gland system in the same way we try to spare known glands."
He's hopeful that that things may be about to get at least a bit better for cancer patients: "Our next step is to find out how we can best spare these new glands and in which patients. If we can do this, patients may experience less side effects which will benefit their overall quality of life after treatment."
A critical thinking framework developed by psychologists can help teach mental skills necessary for our times.
- Researchers propose six levels of critical thinkers: Unreflective thinkers, Challenged thinkers, Beginning thinkers, Practicing thinkers, Advanced thinkers, and Master thinkers.
- The framework comes from educational psychologists Linda Elder and Richard Paul.
- Teaching critical thinking skills is a crucial challenge in our times.
The coronavirus has not only decimated our populations, its spread has also attacked the very nature of truth and stoked inherent tensions between many different groups of people, both at local and international levels. Spawning widespread conspiracy theories and obfuscation by governments, the virus has also been a vivid demonstration of the need for teaching critical thinking skills necessary to survive in the 21st century. The stage theory of critical thinking development, devised by psychologists Linda Elder and Richard Paul, can help us gauge the sophistication of our current mental approaches and provides a roadmap to the thinking of others.
The researchers identified six predictable levels of critical thinkers, from ones lower in depth and effort to the advanced mind-masters, who are always steps ahead.
As the scientists write, moving up on this pyramid of thinking "is dependent upon a necessary level of commitment on the part of an individual to develop as a critical thinker." Using your mind more effectively is not automatic and "is unlikely to take place "subconsciously." In other words – you have to put in the work and keep doing it, or you'll lose the faculty.
Here's how the stages of intellectual development break down:
Stage One: The Unreflective Thinker
These are people who don't reflect about thinking and the effect it has on their lives. As such, they form opinions and make decisions based on prejudices and misconceptions while their thinking doesn't improve.
Unreflective thinkers lack crucial skills that would allow them to parse their thought processes. They also do not apply standards like accuracy, relevance, precision, and logic in a consistent fashion.
How many such people are out there? You probably can guess based on social media comments. As Elder and Paul write, "it is perfectly possible for students to graduate from high school, or even college, and still be largely unreflective thinkers."
Stage Two: The Challenged Thinker
This next level up thinker has awareness of the importance of thinking on their existence and knows that deficiencies in thinking can bring about major issues. As the psychologists explain, to solve a problem, you must first admit you have one.
People at this intellectual stage begin to understand that "high quality thinking requires deliberate reflective thinking about thinking", and can acknowledge that their own mental processes might have many flaws. They might not be able to identify all the flaws, however.
A challenged thinker may have a sense that solid thinking involves navigating assumptions, inferences, and points of view, but only on an initial level. They may also be able to spot some instances of their own self-deception. The true difficulty for thinkers of this category is in not "believing that their thinking is better than it actually is, making it more difficult to recognize the problems inherent in poor thinking," explain the researchers.
Stage Three: The Beginning Thinker
Thinkers at this level can go beyond the nascent intellectual humility and actively look to take control of their thinking across areas of their lives. They know that their own thinking can have blind spots and other problems and take steps to address those, but in a limited capacity.
Beginning thinkers place more value in reason, becoming self-aware in their thoughts. They may also be able to start looking at the concepts and biases underlying their ideas. Additionally, such thinkers develop higher internal standards of clarity, accuracy and logic, realizing that their ego plays a key role in their decisions.
Another big aspect that differentiates this stronger thinker – some ability to take criticism of their mental approach, even though they still have work to do and might lack clear enough solutions to the issues they spot.
Stage Four: The Practicing Thinker
This more experienced kind of thinker not only appreciates their own deficiencies, but has skills to deal with them. A thinker of this level will practice better thinking habits and will analyze their mental processes with regularity.
While they might be able to express their mind's strengths and weaknesses, as a negative, practicing thinkers might still not have a systematic way of gaining insight into their thoughts and can fall prey to egocentric and self-deceptive reasoning.
How do you get to this stage? An important trait to gain, say the psychologists, is "intellectual perseverance." This quality can provide "the impetus for developing a realistic plan for systematic practice (with a view to taking greater command of one's thinking)."
"We must teach in such a way that students come to understand the power in knowing that whenever humans reason, they have no choice but to use certain predictable structures of thought: that thinking is inevitably driven by the questions, that we seek answers to questions for some purpose, that to answer questions, we need information, that to use information we must interpret it (i.e., by making inferences), and that our inferences, in turn, are based on assumptions, and have implications, all of which involves ideas or concepts within some point of view," explain Elder and Paul.
Stage Five: The Advanced Thinker
One doesn't typically get to this stage until college and beyond, estimate the scientists. This higher-level thinker would have strong habits that would allow them to analyze their thinking with insight about different areas of life. They would be fair-minded and able to spot the prejudicial aspects in the points of view of others and their own understanding.
While they'd have a good handle on the role of their ego in the idea flow, such thinkers might still not be able to grasp all the influences that affect their mentality.
The advanced thinker is at ease with self-critique and does so systematically, looking to improve. Among key traits required for this level are "intellectual insight" to develop new thought habits, "intellectual integrity" to "recognize areas of inconsistency and contradiction in one's life," intellectual empathy" to put oneself in the place of others in order to genuinely understand them, and the "intellectual courage" to confront ideas and beliefs they don't necessarily believe in and have negative emotions towards.
Stage Six: The Master Thinker
This is the super-thinker, the one who is totally in control of how they process information and make decisions. Such people constantly seek to improve their thought skills, and through experience "regularly raise their thinking to the level of conscious realization."
A master thinker achieves great insights into deep mental levels, strongly committed to being fair and gaining control over their own egocentrism.
Such a high-level thinker also exhibits superior practical knowledge and insight, always re-examining their assumptions for weaknesses, logic, and biases.
And, of course, a master thinker wouldn't get upset with being intellectually confronted and spends a considerable amount of time analyzing their own responses.
"Why is this so important? Precisely because the human mind, left to its own, pursues that which is immediately easy, that which is comfortable, and that which serves its selfish interests. At the same time, it naturally resists that which is difficult to understand, that which involves complexity, that which requires entering the thinking and predicaments of others," write the researchers.
So how do you become a master thinker? The psychologists think most students will never get there. But a lifetime of practicing the best intellectual traits can get you to that point when "people of good sense seek out master thinkers, for they recognize and value the ability of master thinkers to think through complex issues with judgment and insight."
The significance of critical thinking in our daily lives, especially in these confusing times, so rife with quick and often-misleading information, cannot be overstated. The decisions we make today can truly be life and death.
What's the difference between brainwashing and rehabilitation?
- The book and movie, A Clockwork Orange, powerfully asks us to consider the murky lines between rehabilitation, brainwashing, and dehumanization.
- There are a variety of ways, from hormonal treatment to surgical lobotomies, to force a person to be more law abiding, calm, or moral.
- Is a world with less free will but also with less suffering one in which we would want to live?
Alex is a criminal. A violent and sadistic criminal. So, we decide to do something about it. We're going to "rehabilitate" him.
Using a new and exciting "Ludovico" technique, we'll change his brain chemistry to make him an upstanding, moral citizen. Alex will be forced to watch violent movies as his body is pumped with nausea-inducing drugs. After a while, he'll come to associate violence with this horrible sickness. And, after a course of Ludovico, Alex can happily return to society, never again doing an immoral or illegal act. He'll no longer be a danger to himself or anyone else.
This is the story of A Clockwork Orange by Anthony Burgess, and it raises important questions about the nature of moral decisions, free will, and the limits of rehabilitation.
Today's Clockwork Orange
This might seem like unbelievable science fiction, but it might be truer — and nearer — than we think. In 2010, Dr. Molly Crockett did a series of experiments on moral decision-making and serotonin levels. Her results showed that people with more serotonin were less aggressive or confrontational and much more easy-going and forgiving. When we're full of serotonin, we let insults pass, are more empathetic, and are less willing to do harm.
As Fydor Dostoyevsky wrote in The Brothers Karamazov, if the "entrance fee" for having free will is the horrendous suffering we see all around us, then "I hasten to return my ticket."
The idea that biology affects moral decisions is obvious. Most of us are more likely to be short-tempered and spiteful if we're tired or hungry, for instance. Conversely, we have the patience of a saint if we just have received some good news, had half a bottle of wine, or had sex.
If our decision-making can be manipulated or determined by our biology, should we not try various interventions to prevent the criminally inclined from harming others?
What is the point of prison? This is itself no easy question, and it's one with a rich philosophical debate. Surely one of the biggest reasons is to protect society by preventing criminals from reoffending. This might be achievable by manipulating a felon's serotonin levels, but why not go even further?
Today, we know enough about the brain to have identified a very particular part of the prefrontal cortex responsible for aggressive behavior. We know that certain abnormalities in the amygdala can result in anti-social behavior and rule breaking. If the purpose of the penal system is to rehabilitate, then why not "edit" these parts of the brain in some way? This could be done in a variety of ways.
Credit: Otis Historical Archives National Museum of Health and Medicine via Flickr / Wikipedia
Electroconvulsive therapy (ECT) is a surprisingly common practice in much of the developed world. Its supporters say that it can help relieve major mental health issues such as depression or bipolar disorder as well as alleviate certain types of seizures. Historically, and controversially, it has been used to "treat" homosexuality and was used to threaten those misbehaving in hospitals in the 1950s (as notoriously depicted in One Flew Over the Cuckoo's Nest). Of course, these early and crude efforts at ECT were damaging, immoral, and often left patients barely able to function as humans. Today, neuroscience and ECT are much more sophisticated. If we could easily "treat" those with aggressive or anti-social behavior, then why not?
Ideally, we might use techniques such as ECT or hormonal supplementation, but failing that, why not go even further? Why not perform a lobotomy? If the purpose of the penal system is to change the felon for the better, we should surely use all the tools at our disposal. With one fairly straightforward surgery to the prefrontal cortex, we could turn a violent, murderous criminal into a docile and law-abiding citizen. Should we do it?
Is free will worth it?
As Burgess, who penned A Clockwork Orange, wrote, "Is a man who chooses to be bad perhaps in some way better than a man who has the good imposed upon him?"
Intuitively, many say yes. Moral decisions must, in some way, be our own. Even if we know that our brains determine our actions, it's still me who controls my brain, no one else. Forcing someone to be good, by molding or changing their brain, is not creating a moral citizen. It's creating a law-abiding automaton. And robots are not humans.
And yet, it begs the question: is "free choice" worth all the evil in the world?
If my being brainwashed or "rehabilitated" means children won't die malnourished or the Holocaust would never happen, then so be it. If lobotomizing or neuro-editing a serial killer will prevent them from killing again, is that not a sacrifice worth making? There's no obvious reason why we should value free will above morality or the right to life. A world without murder and evil — even if it meant a world without free choices for some — might not be such a bad place.
As Fyodor Dostoyevsky wrote in The Brothers Karamazov, if the "entrance fee" for having free will is the horrendous suffering we see all around us, then "I hasten to return my ticket." Free will's not worth it.
Do you think the Ludovico technique from A Clockwork Orange is a great idea? Should we turn people into moral citizens and shape their brains to choose only what is good? Or is free choice more important than all the evil in the world?
A simple trick allowed marine biologists to prove a long-held suspicion.
- It's long been suspected that sharks navigate the oceans using Earth's magnetic field.
- Sharks are, however, difficult to experiment with.
- Using magnetism, marine biologists figured out a clever way to fool sharks into thinking they're somewhere that they're not.
For some time, scientists have suspected that sharks belong among the growing number of animals known to navigate using Earth's magnetic field. Testing anything with a shark, though, requires some care.
The key was selecting the right candidate. Keller and his colleagues chose the bonnethead shark, Sphyrna tiburo, a small critter that summers at Turkey Point Shoal off the coast of the Florida State University Coastal and Marine Laboratory with which Keller is affiliated.
Bonnetheads elsewhere have been known to complete 620-mile roundtrip migrations. As the lab's Dean Grubbs puts it, "That's not bad for a shark that is only two to three feet long. The question is how do they find their way back to that same estuary year after year." There's a report of a great white shark migrating between two locations, one in South Africa and another in Australia, year after year.
The research is published in Current Biology.
Keller and his team rounded up 20 local juvenile bonnetheads and transported them into a holding tank at the marine lab. For the tests, the researchers simulated three real-world magnetic fields. As the various magnetic fields were activated, the sharks' movements were captured by GoPro cameras and their average swimming orientations calculated by software.
The first simulation, serving as a control, mimicked the magnetic field of the nearby shoal from which the sharks had been captured. When this field was activated, the sharks essentially acted like they were "home," just swimming around as they do.
A second field was the magnetic equivalent of a location 600 kilometers south of the lab within the Gulf of Mexico. When this field was activated, the sharks, apparently mistaking themselves for being far south in the Gulf, began swimming northward toward the shoal.
The opposite occurred with a field standing in for a location in continental North America 600 km north of their home shoal — the sharks began swimming southward.
"For 50 years," says Keller, "scientists have hypothesized that sharks use the magnetic field as a navigational aid. This theory has been so popular because sharks, skates, and rays have been shown to be very sensitive to magnetic fields. They have also been trained to react to unique geomagnetic signatures, so we know they are capable of detecting and reacting to variation in the magnetic field."
His team's experiments confirm what's long been suspected, Keller says: "Sharks use map-like information from the geomagnetic field as a navigational aid. This ability is useful for navigation and possibly maintaining population structure."