The following introduction was excerpted and adapted from Wikipedia.
Bloom’s taxonomy is a proposed and widely accepted set of hierarchical models used to classify educational learning objectives into levels of complexity and specificity. They cover learning objectives in cognitive, affective and sensory domains. These ideas are frequently used to structure curriculum learning objectives, assessments and activities. However, despite popular belief, the taxonomies themselves have no scientific basis. In the following criticism section, note that there are alternate ways to conceptualize modes of thinking and learning.
The models were named after Benjamin Bloom, who chaired the committee of educators that devised the taxonomy. He edited the first volume of the standard text, Taxonomy of Educational Objectives in 1956. A second edition arrived in 1964, and a fully revised version in 2001.
In the original version of the taxonomy, the cognitive domain is broken into six levels of objectives: Knowledge, Comprehension, Application, Analysis, Synthesis, Evaluation. In the 2001 revised edition of Bloom’s taxonomy, the levels are changed to: Remember, Understand, Apply, Analyze, Evaluate, and Create.
Criticism of Bloom’s taxonomy
As Richard Morshead (1965) pointed out on the publication of the second volume, the classification was not a properly constructed taxonomy: it lacked a systemic rationale of construction.
This was eventually acknowledged in the 2001 revision. Here an attempt was made to create a taxonomy on more systematic lines.
Some consider the three lowest levels as hierarchically ordered, but the three higher levels as parallel.
Some critiques of the taxonomy’s cognitive domain admit the existence of the proposed six categories but question the existence of a sequential, hierarchical link.
Furthermore, the distinction between the categories can be seen as artificial since any given cognitive task may entail a number of processes. Many argue that any attempt to nicely categorize cognitive processes into cut-and-dried classifications undermines the holistic, interrelated nature of cognition.
Misuse of Bloom’s hierarchy
Educators may mistakenly dismiss the lowest levels as unworthy of teaching. However, the learning of lower level skills enable the building of higher level skills.
“Bloom’s taxonomy.” Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 27 Sep. 2018.
Education Week, by Ron Berger
The problem is that both versions present a false vision of learning. Learning is not a hierarchy or a linear process. This graphic gives the mistaken impression that these cognitive processes are discrete, that it’s possible to perform one of these skills separately from others. It also gives the mistaken impression that some of these skills are more difficult and more important than others. It can blind us to the integrated process that actually takes place in students’ minds as they learn.
My critique of this framework is not intended to blame anyone. I don’t assume that Benjamin Bloom and his team, or the group who revised his pyramid, necessarily intended for us to see these skills as discrete or ranked in importance. I also know that thoughtful educators use this framework to excellent ends–to emphasize that curriculum and instruction must focus in a balanced way on the full range of skills, for all students from all backgrounds. But my experience suggests that what most of us take away from this pyramid is the idea that these skills are discrete and hierarchical. That misconception undermines our understanding of teaching and learning, and our work with students.
Ron Berger, Chief Academic Officer at EL Education.
Bloom’s Taxonomy – That Pyramid is a Problem
by Doug Lemov
A couple of useful notes though. 1) Bloom’s is a ‘framework.’ This is to say it an idea—one that’s compelling in many ways perhaps but not based on data or cognitive science, say. In fact it was developed pretty much before there was such a thing as cognitive science. So it’s almost assuredly got some value to it and it’s almost assuredly gotten some things wrong. 2) I was surprised, happy and concerned (all at once) to read the italicized phrase: with the understanding that knowledge was the necessary precondition for putting these skills and abilities into practice.
Ironically this is exactly the opposite of what people interpret Bloom’s to be saying. Generally when teachers talk about “Bloom’s taxonomy,” they talk with disdain about “lower level” questions. They believe, perhaps because of the pyramid image which puts knowledge at the bottom, that knowledge-based questions, especially via recall and retrieval practice, are the least productive thing they could be doing in class. No one wants to be the rube at the bottom of the pyramid.
But this, interestingly is not what Bloom’s argued—at least according to Vanderbilt’s description. Saying knowledge questions are low value and that knowledge is the necessary precondition for deep thinking are very different things. More importantly believing that knowledge questions—even mere recall of facts—are low value doesn’t jibe with the overwhelming consensus of cognitive science, summarized here by Daniel Willingham, who writes,
Data from the last thirty years lead to a conclusion that is not scientifically challengeable: thinking well requires knowing facts, and that’s true not simply because you need something to think about. The very processes that teachers care about most — critical thinking processes such as reasoning and problem solving — are intimately intertwined with factual knowledge that is in long-term memory (not just found in the environment)
In other words there are two parts to the equation. You not only have to teach a lot of facts to allow students to think deeply but you have to reinforce knowledge enough to install it in long-term memory or you can’t do any of the activities at the top of the pyramid. Or more precisely you can do them but they are going to be all but worthless. Knowledge reinforced by recall and retrieval practice, is the precondition.
In the spirit of the FDA which recently revised its omnipresent food pyramid to address misconceptions caused by the diagram created to represent it, I’m going to propose a revision to the Bloom ‘pyramid’ so the graphic is far more representative. I’m calling it Bloom’s Delivery Service. In it, knowledge is not at the bottom of a pyramid but is the fuel that allows the engine of thinking to run. If I had more time for graphic design, I might even turn the pyramid on its side. You probably want to do quite a bit of analysis and synthesis but only if you’ve got comprehension solidly in the bag. In other words you kind of need all of the pieces.
– Doug Lemov
Seyyed Mohammad Ali Soozandehfar and Mohammad Reza Adeli
American Research Journal of English and Literature (ARJEL), Volume 2, 2016
… In 1999, Dr. Lorin Anderson, a former student of Bloom’s, and his colleagues published an updated version of Bloom’s Taxonomy that takes into account a broader range of factors that have an impact on teaching and learning. This revised taxonomy attempts to correct some of the problems with the original taxonomy. Unlike the 1956 version, the revised taxonomy differentiates between “knowing what,” the content of thinking, and
“knowing how,” the procedures used in solving problems.
… Today’s world is a different place, however, than the one Bloom’s Taxonomy reflected in 1956. Educators have learned a great deal more about how students learn and teachers teach and now recognize that teaching and learning encompasses more than just thinking. It also involves the feelings and beliefs of students and teachers as well as the social and cultural environment of the classroom.
Anderson (2000) argues that nearly all complex learning activities require the use of several different cognitive skills. Like any theoretical model, Bloom’s Taxonomy has its strengths and weaknesses. Its greatest strength is that it has taken the very important topic of thinking and placed a structure around it that is usable by practitioners. Those teachers who keep a list of question prompts relating to the various levels of Bloom’s Taxonomy undoubtedly do a better job of encouraging higher-order thinking in their students than those who have no such tool.
On the other hand, as anyone who has worked with a group of educators to classify a group of questions and learning activities according to the Taxonomy can attest, there is little consensus about what seemingly self-evident terms like “analysis,” or “evaluation” mean. In addition, so many worthwhile activities, such as authentic problems and projects, cannot be mapped to the Taxonomy, and trying to do that would diminish their potential as learning opportunities. In the following sections, this study presents several in-depth criticisms:
…. it has been maintained that Bloom’s Taxonomy is more often than not interpreted incorrectly. Booker (2007) believes that “Bloom’s Taxonomy has been used to devalue basic skills education and has promoted “higher order thinking” at its expense” (2007, p.248). In other words, lower order skills such as knowledge and comprehension are being considered as less critical or invaluable skills.
Being referred to as lower order skills does not make knowledge or comprehension any less important, rather they are arguably the most important cognitive skills because knowledge of and comprehension of a subject is vital in advancing up the levels of the taxonomy. Therefore, in line with Booker’s conclusion, the Taxonomy is being improperly used. Bloom never stated that any of his cognitive levels were less important, just that they followed a hierarchical structure. Booker (2007) points out that even Bloom himself recognized that the application of the taxonomy was unexpectedly happening at the K-12 level and much less so at the university/college level.
The Misdirection of American Education
Abstract: Plato wrote that higher order thinking could not start until the student had mastered conventional wisdom. The American educational establishment has turned Plato on his head with the help of a dubious approach to teaching developed by one Benjamin Bloom. Bloom’s taxonomy was intended for higher education, but its misappropriation has resulted in a serious distortion of the purpose of the K–12 years. Michael Booker attributes the inability of American children to compete internationally to a great extent to our reliance on Bloom in expecting critical and advanced thinking from kids who have been trained to regard facts and substantive knowledge as unimportant.
Bloom’s Taxonomy has become influential to the point of dogma in American Colleges of Education.
Bloom’s Taxonomy has been used to devalue basic skills education and haspromoted “higher order thinking”at its expense.
Shortchanging basic skills education has resulted in producing students who misunderstand true higher-order thinking and who are not equipped for advanced education.
…. Soon after it was published, a body of research began to build around theTaxonomy. In 1970, Cox and Wildemann collected an index of the existing research into Bloom’s Taxonomy.12According to their study, 118 research projects of various sorts had been conducted in the previous decade and a half. A review of their data, however, shows that most of the research lacked experimental results that might either confirm or invalidate it. The results noted are not reassuring. Initial studies showed that individuals skilled in the Taxonomy frequently could not agree on the classification of test items or objectives.
… This adds up to an extraordinary misreading of the Taxonomy. Standards intended for college students get pushed down to the K–12 system. Instead of teaching those K–12 students hierarchically, the foundation of the structure is ignored. The push is made to the highest levels of the Taxonomy, especially level six, Evaluation. Since Handbook 1 is currently out of print (a measure, perhaps, of how carefully it is studied in the colleges of education), I will quote its caveats about Evaluation.
For the most part, the evaluations customarily made by an individual are quick decisions not preceded by very careful consideration of the various aspects of the object, idea or activity being judged. These might be termed opinions rather than judgments.…For purposes of classification, only those evaluations which are or can be made with distinct criteria in mind are considered.
Despite these warnings, typical Evaluation questions take the form of “What do you think about x?”and “Do you agree with x?” These questions are often accompanied by praise for what education literature misidentifies as the “SocraticMethod.” The result of this strategy is to occupy class time with vacuous opining.
When I speak with my fellow community college instructors, we rarely complain about student ’lack of advanced intellectual skills. Our chief source of frustration is that they haven’t mastered the basics needed to succeed in college-level work. Since I teach philosophy, I don’t expect my students to come to class knowing any content about my subject area.
Still, it would be lovely if they exited high school with some knowledge of world history, science, English, and geography. A large cohort (much to my frustration) doesn’t know how many grams are in a kilogram or when to use an apostrophe. I have a friend, Dr. Lawrence Barker, who once taught statistics at a state university. Each quarter he quizzed his incoming statistics students about basic math. The majority, he learned, couldn’t determine the square root of one without access to a calculator. He left teaching and is now happily employed by theCenters for Disease Control.
A Roof without Walls: Benjamin Bloom’s Taxonomy and the Misdirection of American Education, Michael Booker, Academic Questions 20(4):347-355 · December 2007
Bloom’s Taxonomy is a classification system of learning objectives. There are three separate domains which are covered: Cognitive, Affective, and Psychomotor. We will be focusing on the Cognitive domain, which organizes thought processes according to six different cognitive levels (below). These levels can be viewed as a stairwell, for which each cognitive process as its own step. Each step, from bottom to top, has its own distinct characteristics. Benjamin Bloom Ph.D., an educational psychologist proposed that all learning occurs in order based on these steps. As you continue to progress up through Bloom’s pyramid, it implies that you have mastered the cognitive processes which you have already passed. Educators use Bloom’s Taxonomy on a regular basis by organizing their lesson plans and creating example questions for their students based on what cognitive level the students are processing at.
This is an example of the Bloom’s Taxonomy Verb Wheel. Every level within the cognitive domain has actions and verbs that are specific to it. This chart illustrates the 6 levels, followed by the verbs that are associated with them. It then shows the different activities which students engage in, which is associated with that level. By utilizing these verbs and activities, it allows educators to address questions in such a way that students “climb the staircase” of Bloom’s Taxonomy and can eventually be able to master the material.
(1) Morshead, Richard W. (1965). “On Taxonomy of educational objectives Handbook II: Affective domain”. Studies in Philosophy and Education. 4 (1)
Introduction: To be added
If an industrial civilization had existed on Earth many millions of years prior to our own era, what traces would it have left and would they be detectable today? We summarize the likely geological fingerprint of the Anthropocene, and demonstrate that while clear, it will not differ greatly in many respects from other known events in the geological record. We then propose tests that could plausibly distinguish an industrial cause from an otherwise naturally occurring climate event.
One of the primary open questions of astrobiology is whether there is extant or extinct life elsewhere the Solar System. Implicit in much of this work is that we are looking for microbial or, at best, unintelligent life, even though technological artifacts might be much easier to find. SETI work on searches for alien artifacts in the Solar System typically presumes that such artifacts would be of extrasolar origin, even though life is known to have existed in the Solar System, on Earth, for eons.
But if a prior technological, perhaps spacefaring, species ever arose in the Solar System, it might have produced artifacts or other technosignatures that have survived to present day, meaning Solar System artifact SETI provides a potential path to resolving astrobiology’s question.
Here, I discuss the origins and possible locations for technosignatures of such a prior indigenous technological species, which might have arisen on ancient Earth or another body, such as a pre-greenhouse Venus or a wet Mars. In the case of Venus, the arrival of its global greenhouse and potential resurfacing might have erased all evidence of its existence on the Venusian surface. In the case of Earth, erosion and, ultimately, plate tectonics may have erased most such evidence if the species lived Gyr ago. Remaining indigenous technosignatures might be expected to be extremely old, limiting the places they might still be found to beneath the surfaces of Mars and the Moon, or in the outer Solar System.
Neuroplasticity is the ability of the brain to change throughout an individual’s life. Research has shown that many aspects of the brain can be altered even through adulthood. However, the developing brain (in the womb, and early childhood) exhibits a much higher degree of plasticity than the adult brain.
Neuroplasticity can be observed at multiple scales, from microscopic changes in individual neurons to larger-scale changes such as cortical remapping in response to injury. Behavior, environmental stimuli, thought, and emotions may also cause neuroplastic change. This has significant implications for learning, memory, and recovery from brain damage.
At the single cell level, synaptic plasticity refers to changes in the connections between neurons, whereas non-synaptic plasticity refers to changes in their intrinsic excitability.
– Adapted from, “Neuroplasticity.” Wikipedia, The Free Encyclopedia. 21 Sep. 2018
The brain is made of several types of nerves connected to each other in an intricate web, always creating new connections as we grow and learn.
I found the following sequence of GIFs on Mr. Gruszka’s Earth Science GIFtionary.
Whenever you learn something new, you grow some dendrites that made a new circuit in your brain.
Neurons send and receive electrical signals between different parts of the brain.
How are neurons connected?
Signals enter a neuron cell body through a dendrite, and then this may send an electrical signal out along the axon, towards another neuron. Dendrites and axon terminals grow relatively easy. Each time we learn something we grow new dendrite and axon terminal connections.
Whenever you continuously practice learning a new skill, your brain rewires itself.
When your brain rewires itself, new patterns are possible.
These new patterns not only store information, they help your brain learn similar information more efficiently. For instance, the more time you spend learning how to read music and play a musical instrument, the easier it will be over time to develop your skills in this area.
This process works best if you continue to challenge yourself, practicing the skills you have and attempting to learn new ones. As you do this, new connections are made in your brain, and to some extent one can literally become smarter, and better at learning.
However, unless your brain is challenged to do something difficult, or review what it already knows how to do, it will not produce new patterns. If you stop practicing and learning, then eventually the brain will begin to lose some of those neural connections.
When the brain prunes dendrites, we forget how to do something that we learned, or forget a fact that we used to know. In this sense, we say “Use it or lose it.”
Usually, all the dendrites required for a certain skill are not pruned, so we are in luck. With review and practice, we can make new connections that replace the lost ones.
What is meant by brain plasticity? The flexibility of the brain to make new connections and patterns:
This is because “plastic” does not just mean the material we make things out of. It has a second meaning of flexible, or changeable.
Also, brain cells can even travel within the brain to become neurons where they are needed. For instance, when neurons die, new cells can migrate to where they are needed and become neurons. This can happen throughout life.
Antibiotics bill bacteria.
They don’t kill viruses, fungi, or parasites.
Antibiotics work by blocking vital processes in bacteria, killing the bacteria or stopping them from multiplying. This helps the body’s natural immune system to fight the bacterial infection. Different antibiotics work against different types of bacteria.
- Antibiotics that affect a wide range of bacteria are called broad spectrum antibiotics (eg, amoxicillin and gentamicin).
- Antibiotics that affect only a few types of bacteria are called narrow spectrum antibiotics (eg, penicillin).
Different types of antibiotics work in different ways. For example, penicillin destroys bacterial cell walls, while other antibiotics can affect the way the bacterial cell works.
Doctors choose an antibiotic according to the bacteria that usually cause a particular infection. Sometimes your doctor will do a test to identify the exact type of bacteria causing your infection and its sensitivity to particular antibiotics.
Antibiotic medicines may contain one or more active ingredients and be available under different brand names. The active ingredient is the chemical in a medicine that makes it work. The medicine label should tell you the active ingredient and the brand name.
_ from NPS MedicineWise
all the ways
from PDB-101 is developed by the RCSB PDB,
8.1 Describe how the body fights germs and disease naturally and with medicines and
8.5 Identify ways individuals can reduce risk factors related to communicable and chronic diseases
8.6 Describe the importance of early detection in preventing the progression of disease
8.7 Explain the need to follow prescribed health care procedures given by parents and health care providers
8.13 Explain how the immune system functions to prevent and combat disease
8.19 Explain the prevention and control of common communicable infestations, diseases, and infections
Inoculations use weakened germs (or parts of them) to stimulate the body’s immune system to react. This reaction prepares the body to fight subsequent invasions by actual germs of that type. Some inoculations last for life. 8F/H4
If the body’s immune system cannot suppress a bacterial infection, an antibacterial drug may be effective—at least against the types of bacteria it was designed to combat. Less is known about the treatment of viral infections, especially the common cold. However, more recently, useful antiviral drugs have been developed for several major kinds of viral infections, including drugs to fight HIV, the virus that causes AIDS. 8F/M6** (SFAA)
Pasteur found that infection by disease organisms (germs) caused the body to build up an immunity against subsequent infection by the same organisms. He then produced vaccines that would induce the body to build immunity to a disease without actually causing the disease itself. 10I/M3*
Investigations of the germ theory by Pasteur, Koch, and others in the 19th century firmly established the modern idea that many diseases are caused by microorganisms. Acceptance of the germ theory has led to changes in health practices. 10I/M4*
Current health practices emphasize sanitation, the safe handling of food and water, the pasteurization of milk, isolation, and aseptic surgical techniques to keep germs out of the body; vaccinations to strengthen the body’s immune system against subsequent infection by the same kind of microorganisms; and antibiotics and other chemicals and processes to destroy microorganisms. 10I/M7** (BSL)
For now, this intro has been adapted from Wikipedia.
More references, updates, and original work will be added over the next year.
The science wars is a series of intellectual exchanges, between scientific realists and postmodernist critics, about the nature of scientific theory and intellectual inquiry. They took place principally in the United States in the 1990s in the academic and mainstream press. Scientific realists (such as Norman Levitt, Paul R. Gross, Jean Bricmont and Alan Sokal) argued that scientific knowledge is real, and accused the postmodernists of having effectively rejected scientific objectivity, the scientific method, Empiricism, and scientific knowledge.
Postmodernists interpreted Thomas Kuhn‘s ideas about scientific paradigms to mean that scientific theories are social constructs, and philosophers like Paul Feyerabend argued that other, non-realist forms of knowledge production were better suited to serve people’s personal and spiritual needs.
Though much of the theory associated with ‘postmodernism’ (see poststructuralism) did not make any interventions into the natural sciences, the scientific realists took aim at its general influence. The scientific realists argued that large swaths of scholarship, amounting to a rejection of objectivity and realism, had been influenced by major 20th Century poststructuralist philosophers (such as Jacques Derrida, Gilles Deleuze, Jean-François Lyotard and others), whose work they declare to be incomprehensible or meaningless. They implicate a broad range of fields in this trend, including cultural studies, cultural anthropology, feminist studies, comparative literature, media studies, and science and technology studies. They accuse those postmodernist critics who did actually discuss science of having a limited understanding of it.
Higher Superstition: The Academic Left and Its Quarrels with Science, Paul R. Gross and Norman Levitt, 1994
Fashionable Nonsense: Postmodern Intellectuals’ Abuse of Science, Alan Sokal and Jean Bricmont, 1999
In 1996, Alan Sokal published an essay in the hip intellectual magazine Social Text parodying the scientific but impenetrable lingo of contemporary theorists. Here, Sokal teams up with Jean Bricmont to expose the abuse of scientific concepts in the writings of today’s most fashionable postmodern thinkers. From Jacques Lacan and Julia Kristeva to Luce Irigaray and Jean Baudrillard, the authors document the errors made by some postmodernists using science to bolster their arguments and theories. Witty and closely reasoned, Fashionable Nonsense dispels the notion that scientific theories are mere “narratives” or social constructions, and explored the abilities and the limits of science to describe the conditions of existence.
I want to share these ideas with other educators and with students.
Zombie-Based Learning (ZBL) is the brainchild of David Hunter, former teacher from the Bellevue Big Picture school, in a suburb of Seattle, Washington. It uses Project-Based Learning to encourage active engagement, problem solving and critical thinking skills.
When the zombies attack, where should we run, where regroup, and where rebuild our lives? Those questions, key to survival, can focus student attention on a highly motivating and dangerously overlooked fact: Geography skills can save you from the zombie apocalypse!
Use students’ natural desire to survive zombie assaults to motivate study of a complete curriculum based on the 2012 National Geography Standards, and then to apply those skills in a series of scenarios based on surviving when the attacks come to your own neighborhood.
Making History is Project-Based Learning curriculum created by award-winning teacher David Hunter, designed for standards-based classrooms. Launched on Kickstarter, it’s nine units with projects for middle school students. Teach cross-content or by individual subject, with a time travel backstory to drive students’ interest and engagement. The narrative follows a group of entrepreneurial and altruistic students who go back in time, and work together to invent or discover critical breakthroughs BEFORE they occur in our true historical timeline.
He Got Schizophrenia. He Got Cancer. And Then He Got Cured.
A bone-marrow transplant treated a patient’s leukemia — and his delusions, too. Some doctors think they know why.
By Moises Velasquez-Manoff
Mr. Velasquez-Manoff is a science writer.
The man was 23 when the delusions came on. He became convinced that his thoughts were leaking out of his head and that other people could hear them. When he watched television, he thought the actors were signaling him, trying to communicate. He became irritable and anxious and couldn’t sleep.
Dr. Tsuyoshi Miyaoka, a psychiatrist treating him at the Shimane University School of Medicine in Japan, eventually diagnosed paranoid schizophrenia. He then prescribed a series of antipsychotic drugs. None helped. The man’s symptoms were, in medical parlance, “treatment resistant.”
A year later, the man’s condition worsened. He developed fatigue, fever and shortness of breath, and it turned out he had a cancer of the blood called acute myeloid leukemia. He’d need a bone-marrow transplant to survive. After the procedure came the miracle. The man’s delusions and paranoia almost completely disappeared. His schizophrenia seemingly vanished.
Years later, “he is completely off all medication and shows no psychiatric symptoms,” Dr. Miyaoka told me in an email. Somehow the transplant cured the man’s schizophrenia.
A bone-marrow transplant essentially reboots the immune system. Chemotherapy kills off your old white blood cells, and new ones sprout from the donor’s transplanted blood stem cells. It’s unwise to extrapolate too much from a single case study, and it’s possible it was the drugs the man took as part of the transplant procedure that helped him. But his recovery suggests that his immune system was somehow driving his psychiatric symptoms.
At first glance, the idea seems bizarre — what does the immune system have to do with the brain? — but it jibes with a growing body of literature suggesting that the immune system is involved in psychiatric disorders from depression to bipolar disorder.
The theory has a long, if somewhat overlooked, history. In the late 19th century, physicians noticed that when infections tore through psychiatric wards, the resulting fevers seemed to cause an improvement in some mentally ill and even catatonic patients.
Inspired by these observations, the Austrian physician Julius Wagner-Jauregg developed a method of deliberate infection of psychiatric patients with malaria to induce fever. Some of his patients died from the treatment, but many others recovered. He won a Nobel Prize in 1927.
One much more recent case study relates how a woman’s psychotic symptoms — she had schizoaffective disorder, which combines symptoms of schizophrenia and a mood disorder such as depression — were gone after a severe infection with high fever.
Modern doctors have also observed that people who suffer from certain autoimmune diseases, like lupus, can develop what looks like psychiatric illness. These symptoms probably result from the immune system attacking the central nervous system or from a more generalized inflammation that affects how the brain works.
Indeed, in the past 15 years or so, a new field has emerged called autoimmune neurology. Some two dozen autoimmune diseases of the brain and nervous system have been described. The best known is probably anti-NMDA-receptor encephalitis, made famous by Susannah Cahalan’s memoir “Brain on Fire.” These disorders can resemble bipolar disorder, epilepsy, even dementia — and that’s often how they’re diagnosed initially. But when promptly treated with powerful immune-suppressing therapies, what looks like dementia often reverses. Psychosis evaporates. Epilepsy stops. Patients who just a decade ago might have been institutionalized, or even died, get better and go home.
Admittedly, these diseases are exceedingly rare, but their existencesuggests there could be other immune disorders of the brain and nervous system we don’t know about yet.
Dr. Robert Yolken, a professor of developmental neurovirology at Johns Hopkins, estimates that about a third of schizophrenia patients show some evidence of immune disturbance. “The role of immune activation in serious psychiatric disorders is probably the most interesting new thing to know about these disorders,” he told me.
Studies on the role of genes in schizophrenia also suggest immune involvement, a finding that, for Dr. Yolken, helps to resolve an old puzzle. People with schizophrenia tend not to have many children. So how have the genes that increase the risk of schizophrenia, assuming they exist, persisted in populations over time? One possibility is that we retain genes that might increase the risk of schizophrenia because those genes helped humans fight off pathogens in the past. Some psychiatric illness may be an inadvertent consequence, in part, of having an aggressive immune system.
Which brings us back to Dr. Miyaoka’s patient. There are other possible explanations for his recovery. Dr. Andrew McKeon, a neurologist at the Mayo Clinic in Rochester, Minn., a center of autoimmune neurology, points out that he could have suffered from a condition called paraneoplastic syndrome. That’s when a cancer patient’s immune system attacks a tumor — in this case, the leukemia — but because some molecule in the central nervous system happens to resemble one on the tumor, the immune system also attacks the brain, causing psychiatric or neurological problems. This condition was important historically because it pushed researchers to consider the immune system as a cause of neurological and psychiatric symptoms. Eventually they discovered that the immune system alone, unprompted by malignancy, could cause psychiatric symptoms.
Another case study from the Netherlands highlights this still-mysterious relationship. In this study, on which Dr. Yolken is a co-author, a man with leukemia received a bone-marrow transplant from a schizophrenic brother. He beat the cancer but developed schizophrenia. Once he had the same immune system, he developed similar psychiatric symptoms.
The bigger question is this: If so many syndromes can produce schizophrenia-like symptoms, should we examine more closely the entity we call schizophrenia?
Some psychiatrists long ago posited that many “schizophrenias” existed — different paths that led to what looked like one disorder. Perhaps one of those paths is autoinflammatory or autoimmune.
If this idea pans out, what can we do about it? Bone marrow transplant is an extreme and risky intervention, and even if the theoretical basis were completely sound — which it’s not yet — it’s unlikely to become a widespread treatment for psychiatric disorders. Dr. Yolken says that for now, doctors treating leukemia patients who also have psychiatric illnesses should monitor their psychiatric progress after transplantation, so that we can learn more.
And there may be other, softer interventions. A decade ago, Dr. Miyaoka accidentally discovered one. He treated two schizophrenia patients who were both institutionalized, and practically catatonic, with minocycline, an old antibiotic usually used for acne. Both completely normalized on the antibiotic. When Dr. Miyaoka stopped it, their psychosis returned. So he prescribed the patients a low dose on a continuing basis and discharged them.
Minocycline has since been studied by others. Larger trials suggest that it’s an effective add-on treatment for schizophrenia. Some have argued that it works because it tamps down inflammation in the brain. But it’s also possible that it affects the microbiome — the community of microbes in the human body — and thus changes how the immune system works.
Dr. Yolken and colleagues recently explored this idea with a different tool: probiotics, microbes thought to improve immune function. He focused on patients with mania, which has a relatively clear immunological signal. During manic episodes, many patients have elevated levels of cytokines, molecules secreted by immune cells. He had 33 mania patients who’d previously been hospitalized take a probiotic prophylactically. Over 24 weeks, patients who took the probiotic (along with their usual medications) were 75 percent less likely to be admitted to the hospital for manic attacks compared with patients who didn’t.
The study is preliminary, but it suggests that targeting immune function may improve mental health outcomes and that tinkering with the microbiome might be a practical, cost-effective way to do this.
Watershed moments occasionally come along in medical history when previously intractable or even deadly conditions suddenly become treatable or preventable. They are sometimes accompanied by a shift in how scientists understand the disorders in question.
We now seem to have reached such a threshold with certain rare autoimmune diseases of the brain. Not long ago, they could be a death sentence or warrant institutionalization. Now, with aggressive treatment directed at the immune system, patients can recover. Does this group encompass a larger chunk of psychiatric disorders? No one knows the answer yet, but it’s an exciting time to watch the question play out.
Moises Velasquez-Manoff, the author of “An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases” and an editor at Bay Nature magazine, is a contributing opinion writer.