Jon Hamilton Researchers appear to have shown how the brain creates two different kinds of thirst. The process involves two types of brain cells, one that responds to a decline in fluid in our bodies, while the other monitors levels of salt and other minerals, a team reports in the journal Nature. Together, these specialized thirst cells seem to determine whether animals and people crave pure water or something like a sports drink, which contains salt and other minerals. "Our brain can detect these two distinct stimuli with different cell types," says Yuki Oka, a professor of biology at Caltech and the study's lead author. The finding appears to help answer "this question that we've been trying to ask for decades and decades and decades," says Sean Stocker, a professor at the University of Pittsburgh who studies water and salt balance in the body. Stocker was not involved in the study. Oka's research is part of an effort to understand the brain biology underlying behavior that's seen in people and many animals. Article continues after sponsor message For example, people who've just finished a long, sweaty workout often experience a special kind of thirst. "Pure water doesn't do it, right? It's not enough," Oka says. "You need water and salt to recover. And we can easily imagine that under such condition, we crave [a] sport drink." Sports drinks like Gatorade generally include a mix of salt and sugar, as well as water. To understand what triggers this type of thirst, Oka's team studied cells in two regions of mouse brains. Both regions are known to contain neurons involved in the sensation of thirst. © 2020 npr

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 27527 - Posted: 10.16.2020

Paulina Villegas Texas Gov. Greg Abbott issued a disaster declaration in Brazoria County on Sunday after the discovery in the local water supply system of an amoeba that can cause a rare and deadly infection of the brain. “The state of Texas is taking swift action to respond to the situation and support the communities whose water systems have been impacted by this ameba,” Abbott (R) in a news release Sunday. “I urge Texans in Lake Jackson to follow the guidance of local officials and take the appropriate precautions to protect their health and safety as we work to restore safe tap water in the community.” The governor’s declaration follows an investigation of the death of 6-year-old Josiah McIntyre in Lake Jackson this month after he contracted the brain-eating microbe, which prompted local authorities and experts from the Centers for Disease Control and Prevention to test the water. The preliminary results came back Friday, showing that three out of 11 samples collected tested positive. One of the samples came from a hose bib at the boy’s home, Lake Jackson City Manager Modesto Mundo said, according to CBS News. The others came from a “splash pad” play fountain and a hydrant. “The notification to us at that time was that he had played at one of [the] play fountains and he may have also played with a water hose at the home,” Mundo said. On Friday night, the Brazosport Water Authority issued a do-not-use advisory for eight communities after confirmation of the presence of Naegleria fowleri, which destroys brain tissue, then causes swelling of the brain, known as amebic meningoencephalitis. It urged residents to not use the tap water for drinking and cooking. © 1996-2020 The Washington Post

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27499 - Posted: 09.30.2020

By Sam Roberts Donald Kennedy, a neurobiologist who headed the Food and Drug Administration before becoming president of Stanford University, where he oversaw major expansions of its campus and curriculum and weathered a crisis over research spending, died on April 21 in Redwood City, Calif. He was 88. His death, at a residential care facility, was caused by complications of the new coronavirus, his wife, Robin Kennedy, said. He had suffered a severe stroke in 2015. Stanford had been Dr. Kennedy’s life since 1960, when, not yet 30, he joined its faculty as an assistant professor of biology. And except for a stint in the late 1970s as head of the F.D.A. under President Jimmy Carter, he remained wedded to the university, becoming provost and then president in 1980, beginning an 11-year tenure. It was a productive one. During his presidency the university opened the Stanford Humanities Center and campuses in Oxford, England; Kyoto, Japan; and Washington; diversified the Western culture curriculum; and raised $1.2 billion in a five-year centennial campaign, although by the end of the decade the university was facing deficits. His tenure also coincided with fiery debates over antiwar protests and academic freedom by both professors and students, divestiture of the university’s holdings in companys doing business in South Africa, and $160 million in damage inflicted by the Loma Prieta Earthquake in 1989. A would-be writer who had become a neurobiologist in college adventitiously, Dr. Kennedy found his leadership under the microscope in the early 1990s, when the university was accused — and later cleared — of improperly billing the Navy for research expenses. The accusations were aired by federal auditors and Representative John D. Dingell Jr., a tenacious Michigan Democrat, who said that Stanford may have billed the government for as much as $200 million in improper expenses on research contracts for over a decade. © 2020 The New York Times Company

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 27214 - Posted: 04.27.2020

By Laura Sanders Neuroscientists love a good metaphor. Through the years, plumbing, telegraph wires and computers have all been enlisted to help explain how the brain operates, neurobiologist and historian Matthew Cobb writes in The Idea of the Brain. And like any metaphor, those approximations all fall short. Cobb leads a fascinating tour of how concepts of the brain have morphed over time. His writing is clear, thoughtful and, when called for, funny. He describes experiments by neurosurgeon Wilder Penfield, who zapped awake patients’ brains with electricity to provoke reactions. Zapping certain places consistently dredged up memories, which Cobb calls “oneiric experiences.” His footnote on the term: “Look it up. It’s exactly the right word.” I did, and it was. Cobb runs though the history of certain concepts used to explain how the brain works, including electricity, evolution and neurons. Next comes a section on the present, which includes discussions of memory, circuits and consciousness. Cobb offers tastes of the latest research, and a heavy dose of realism. Memory studies have made progress, but “we are still far from understanding what is happening when we remember,” Cobb writes. Despite big efforts, “we still only dimly understand what is going on when we see.” Our understanding of how antidepressants work? “Virtually non-existent.” This real talk is refreshing, and Cobb uses it to great effect to argue that neuroscience is stymied. “There have been many similar moments in the past, when brain researchers became uncertain about how to proceed,” he writes. Scientists have amassed an impressive stockpile of brain facts, but a true understanding of how the brain works eludes us. © Society for Science & the Public 2000–2020

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 20: ; Chapter 15: Language and Lateralization
Link ID: 27206 - Posted: 04.22.2020

Kristen Jordan Shamus, Detroit Free Press A 58-year-old woman hospitalized in the Henry Ford Health System who has the new coronavirus developed a rare complication: encephalitis. In a case report published online Tuesday in the journal Radiology, a team of doctors say the woman tested positive for the coronavirus, but also developed a case of acute necrotizing encephalitis, or ANE, a central nervous infection that mostly afflicts young children. It is believed to be the first published case linking COVID-19 and acute necrotizing encephalitis. The rare and serious brain disease can develop in people who have a viral infection, and causes lesions to form in the brain, tissue death and symptoms such as seizures, drowsiness, confusion and coma. The woman, who was identified as an airline worker, had several days of fever, cough and muscle aches, and was taken by ambulance March 19 to a Henry Ford emergency room, said Dr. Elissa Fory, a Henry Ford neurologist. The patient also showed signs of confusion, lethargy and disorientation. A flu test turned up negative but a rapid COVID-19 test, developed in-house by Henry Ford’s clinical microbiology lab, confirmed she had the coronavirus, Fory said. When the woman remained lethargic, doctors ordered repeat CT and MRI scans, which revealed abnormal lesions in both thalami and temporal lobes, parts of the brain that control consciousness, sensation and memory function. These scans confirmed doctors’ early suspicions.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27160 - Posted: 04.02.2020

Eric Haseltine A recent bulletin from physicians in the UK described the loss of smell and taste in COVID-19 patients, suggesting that the virus might affect parts of the central nervous system, in addition to its well-known affinity for the respiratory system. Indeed, in an earlier outbreak of coronavirus in China, Hong Kong researcher Dr. K.K. Lau and co-workers found that some patients exhibited convulsions, delirium and restlessness, while Dr. Jun Xu, of the Guangzhou Institute of Respiratory Diseases estimated that 4-5% of all SARS coronavirus patients displayed central nervous system symptoms. Some SARS coronavirus patients have even exhibited marked brain damage on CAT scans. In the latest outbreak of coronavirus, evidence of central nervous system involvement is accumulating, such as a March 21st report by Dr. Asia Filatov of Charles E. Schmidt College of Medicine, that a COVID-19 patient exhibited encephalopathy (brain disease). And recent data from Wuhan, described in the March 12 edition of Neurology Today, indicate that neurological symptoms, such as "altered consciousness," occur in up to one third of COVID-19 cases. But could central nervous system action of COVID-19 directly contribute to the acute respiratory distress associated with the disease? The answer might be “yes” according to recent collaborative research from Drs. Y.C. LI and W.Z. Bai Dr. T. and Hashikawa in Japan. Writing in the Feb 27 edition of the Journal of Medical Virology, Li and colleagues, cite research on coronavirus showing that sometimes SARS-Cov infects brainstem centers that control respiration, making it difficult for infected patients to breathe spontaneously. © 2020 Sussex Publishers, LLC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27142 - Posted: 03.25.2020

By Brian Platzer Three years ago I wrote an essay for Well about the chronic dizziness that had devastated my life. In response, I received thousands of letters, calls, tweets, emails and messages from Times readers who were grateful to see a version of their own story made public. Their symptoms varied. While some experienced a constant disequilibrium and brain fog that were similar to mine, others had become accustomed to a pattern of short periods of relative health alternating with longer periods of vertigo. Most of them, like me, felt that family and friends often didn’t understand how dizziness could be so debilitating. They told me that the combination of the loneliness and feelings of uselessness that come from an inability to work or spend time with family led to despair and depression. And, most commonly, they felt that the medical system made them feel responsible for their own suffering. “Doctors began to suggest that anxiety or depression were the cause of my symptoms,” a young woman from Connecticut wrote. “I eventually gave up on the quest for answers, as their attitudes added stress to an already stressful reality.” “Have been to so many doctors that keep saying, ‘It’s all in your head. There’s nothing wrong with you,’” wrote an older woman from Ohio. “Mostly been told there is nothing they can find,” wrote a middle-aged woman from Illinois. Her doctor told her it was probably just depression and anxiety. Dizziness is among the most common reasons people visit their doctor in the United States. When patients first experience prolonged dizziness, they may go to an emergency room or to see their primary care physician. That’s what I did. And I heard what most patients hear: “People get dizzy for all sorts of reasons, and it should resolve itself soon.” It’s true that dizziness often is a temporary symptom. The most common causes of dizziness are benign paroxysmal positional vertigo (caused by displaced pieces of small bone-like calcium in the inner ear), and vestibular neuritis (dizziness attributed to a viral infection or tiny stroke of the vestibular nerve), both of which typically last only weeks or months. © 2020 The New York Times Company

Related chapters from BN: Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 27036 - Posted: 02.13.2020

By Bradley Berman The day is approaching when commuters stuck in soul-crushing traffic will be freed from the drudgery of driving. Companies are investing billions to devise sensors and algorithms so motorists can turn our attention to where we like it these days: our phones. But before the great promise of multitasking on the road can be realized, we need to overcome an age-old problem: motion sickness. “The autonomous-vehicle community understands this is a real problem it has to deal with,” said Monica Jones, a transportation researcher at the University of Michigan. “That motivates me to be very systematic.” So starting in 2017, Ms. Jones led a series of studies in which more than 150 people were strapped into the front seat of a 2007 Honda Accord. They were wired with sensors and set on a ride that included roughly 50 left-hand turns and other maneuvers. Each subject was tossed along the same twisty route for a second time but also asked to complete a set of 13 simple cognitive and visual tasks on an iPad Mini. About 11 percent of the riders got nauseated or, for other reasons, asked that the car be stopped. Four percent vomited. Ms. Jones takes no joy in documenting her subjects’ getting dizzy, hyperventilating or losing their lunch. She feels their pain. Ms. Jones, a chronic sufferer of motion sickness, has experienced those discomforts in car back seats all her life. “I don’t remember not experiencing it,” she said. “As I’m getting older, it’s getting worse.” It’s also getting worse for the legions of commuters hailing Ubers or taxis and hopping in, barely lifting their gaze from a screen in the process. © 2020 The New York Times Company

Related chapters from BN: Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 26976 - Posted: 01.21.2020

Lateshia Beachum A Chinese man sought medical attention for seizures and a headache that lasted nearly a month. Doctors found that tapeworms from undercooked meat were causing his pain. Researchers at the First Affiliated Hospital of Zhejiang University published a paper last week that details the plight of 46-year-old construction worker Zhu (an alias for the patient) in the eastern Zhejiang province of China who bought pork and mutton about a month ago for a spicy hot pot broth. Days later, the man started feeling dizzy, having headaches and experiencing epilepsy-like symptoms such as limb twitching and mouth foaming while trying to sleep at night, according to the report. Co-workers witnessed one of Zhu’s episodes and dialed for emergency help. He was seen at a hospital where scans and tests showed that he had multiple intracranial calcifications, abnormal deposits of calcium in blood vessels to the brain; and multiple intracranial lesions, according to researchers. Medical staff wanted to examine him further, but he dismissed their concerns because he didn’t want to spend more money, according to the report. The symptoms that sent Zhu to the hospital persisted after he left, researchers reported. He became frightened. He spoke with his relatives about seeking medical treatment before deciding on care at the First Affiliated Hospital of Zhejiang University Medical College. Huang Jianrong, the hospital’s chief doctor, consulted Zhu and learned that he had eaten pork and mutton not too long ago, according to the report.

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 26855 - Posted: 11.29.2019

By Michelle Roberts Health editor, BBC News online An infectious disease that can harm the brain and is spread to people by tick bites has been identified in ticks in the UK for the first time. Public Health England (PHE) says it has confirmed cases of tick-borne encephalitis virus in ticks from two parts of England - Thetford Forest and an area on the Hampshire-Dorset border. PHE says the risk to people is still "very low". It is monitoring the situation to check how common the infected ticks may be. What is it? A tick is a tiny, spider-like creature that lives in undergrowth and on animals, including deer and dogs. People who spend time walking in countryside areas where infected ticks can be found are at risk of being bitten and catching diseases they carry. Tick-borne encephalitis virus is already circulating in mainland Europe and Scandinavia, as well as Asia. Evidence now shows it has reached the UK. How it got here is less clear. Experts say infected ticks may have hitched a ride on migratory birds. Earlier this year, a European visitor, who has since recovered, became ill after being bitten by a tick while in the New Forest area, Public Health England says. Further investigations revealed infected ticks were present in two locations in England. Should I worry? Ticks are becoming more common across many parts of the UK, largely due to increasing deer numbers. Being bitten by one doesn't necessarily mean you will get sick. Dr Nick Phin, from Public Health England, said: ''These are early research findings and indicate the need for further work. However, the risk to the general public is currently assessed to be very low." Most people who catch the virus will have no or only mild flu-like symptoms. But the disease can progress to affect the brain and central nervous system and can sometimes be fatal. © 2019 BBC

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 26782 - Posted: 11.02.2019

By Gary Stix Sigmund Freud never uttered the word neuroscience. Neither did Santiago Ramón y Cajal. It was biophysicist Francis Schmitt who grafted “neuro” with “science” in 1962 when he established the Neurosciences Research Program at MIT. The new moniker was intended to encompass a merging of relevant neuro disciplines, ranging as far afield as physiology, psychology, immunology, physics and chemistry. Brains and behaviors have been scrutinized for millennia. But as psychology blogger Vaughn Bell has pointed out, the 1960s marked a shift in perspective. Neuroscience was the formal name given by Schmitt. But the period represented the beginnings of a “neuroculture,” that put brain science on a pedestal —even leading to the familiar meme proclaiming “my brain made me do it.” One example was rooted in pharmaceutical companies’ development of psychiatric drugs that resulted in their investing “millions both into divining the neurochemistry of experience and into massive marketing campaigns that linked brain functions to the psyche,” Bell notes. The field received an adrenaline boost precisely 50 years ago with the founding of the Society for Neuroscience, allowing Schmitt’s collaborative vision to be globally shared. SFN’s first annual meeting in 1971 drew 1,395 attendees to Washington, D.C. This year’s wrapped up on October 23, bringing more than 27,500 to Chicago—and the annual numbers have occasionally topped 30,000. SFN now boasts 37,000 members from more than 95 countries. © 2019 Scientific American

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 20: ; Chapter 4: Development of the Brain
Link ID: 26766 - Posted: 10.30.2019

By Kate Murphy Maybe it was because when the waiter asked, “Still or sparkling?” you chose sparkling. It could have also been that you were ravenous and ate a little too much. Or, possibly, it was your ex, who happened to be dining at the same restaurant and stood a little too long over your table making awkward small talk. All of these things, hic, might cause spasms, hic, in your diaphragm, hic. Referred to in the medical literature as singultus (from the Latin singult, which means gasp or sob), hiccups are familiar to anyone who has ever taken a breath. In fact, you begin to hiccup while still in the womb. Most people hiccup the most during childhood, with the bouts becoming less frequent over time, but even in adulthood, hiccups are still a common, and annoying, occurrence. Just as we all have our own particular way of sneezing, we all have a unique way of hiccuping that can range from four to 60 hiccups per minute. Most hiccups are benign and last only a few minutes or hours. But sometimes hiccups are indicative of a more serious health issue, particularly when they recur or don’t go away for days, weeks or years. Beyond being embarrassing, the muscle contractions can be physically exhausting. They can interrupt sleep and make it hard to eat. Approximately 4,000 people in the United States are admitted to the hospital every year for hiccups. The patient with the longest recorded case, according to Guinness World Records, was Charles Osborne of Anthon, Iowa, who hiccuped for 68 years straight. He claimed it started while attempting to weigh a hog before slaughtering it. Doctors say there are as many causes for hiccups as there are crazy remedies, including tugging on your tongue, standing on your head and swallowing granulated sugar. Some actually work. Others are more likely just entertainment for friends and family who watch while you try to cure yourself. © 2019 The New York Times Company

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 20: ; Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 26503 - Posted: 08.15.2019

By Jennifer Leman, Liz Tormes Art and neuroscience have been intertwined for centuries. Early surgeons and scientists who poked and prodded inside cranial cavities—such as Santiago Ramón y Cajal—often drew what they saw. These artistic renderings played a critical role in helping researchers grapple with the mysteries of our most vital organ. (Cajal even shared the Nobel Prize in Physiology or Medicine in 1906 for his drawings.) Methods for exploring the brain have (thankfully) changed, and our understanding has evolved. The desire to visualize what we discover, however, has persisted. For the ninth year in a row, the Netherlands Institute for Neuroscience in Amsterdam has published the winners of its annual Art of Neuroscience competition. The contest celebrates artists and scientists who strive to illustrate the brain’s complexities. This year’s entrants questioned the origins of imagination, imaged collagen fiber, modeled starlike brain cells called astrocytes and explored other intricacies. Presented below—selected from 87 submissions representing 25 countries—are the winning entry, four honorable mentions and five works selected by Scientific American’s editors.* This video employs three artificial-intelligence-based computing systems inspired by human brain networks. The resulting three neural networks simulate the brain’s ability to generate abstract images, sounds and concepts inspired by prior experiences, a phenomenon better known as imagination. In the winning video, produced by members of the pt9 art group at Far Eastern Federal University in Russia, one neural network produces a string of jarring images prompted by a catalogue of existing photographs; a second neural network generates image descriptions; and the third neural network reads the descriptions aloud. © 2019 Scientific American

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 26466 - Posted: 07.30.2019

By Jacey Fortin A man in North Carolina died on Monday after he went swimming in a lake and was infected by Naegleria fowleri, a single-celled organism known as the “brain-eating amoeba.” The man, Eddie Gray, 59, fell ill after he visited the Fantasy Lake Water Park in Cumberland County July 12, the North Carolina Department of Health and Human Services said in a statement on Thursday. Naegleria fowleri infections are rare, but deadly. There were 145 known infected people in the United States from 1962 through 2018, and all but four cases were fatal. The amoeba is typically found in warm freshwater, and the majority of cases in the United States have occurred in Florida and Texas. “Mr. Gray’s death was tragic and untimely,” Justin Plummer, a lawyer representing his estate, said in a statement. “The family is currently asking for privacy and respect during this difficult time.” According to his obituary, Mr. Gray was an active member of the Sedge Garden United Methodist Church who enjoyed kayaking, camping, hunting, fishing and NASCAR. “Our sympathies are with the family and loved ones,” Zack Moore, North Carolina’s state epidemiologist, said in a statement. “People should be aware that this organism is present in warm freshwater lakes, rivers and hot springs across North Carolina, so be mindful as you swim or enjoy water sports.” According to the North Carolina health department, Naegleria fowleri “does not cause illness if swallowed but can be fatal if forced up the nose, as can occur during diving, water-skiing or other water activities.” © 2019 The New York Times Company

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 26454 - Posted: 07.26.2019

By Richard Klasco, M.D. Q. Please explain positional vertigo. Two of my siblings have woken up in the morning with it. What do you do if you experience it? A. Positional vertigo is a common type of dizziness that can be treated with a simple maneuver. Vertigo is an illusory sensation of motion that is often accompanied by intense nausea. Benign paroxysmal positional vertigo, or B.P.P.V., is the medical term for positional vertigo. It is important to use this term, as there are other types of vertigo with different causes and treatments. B.P.P.V. is caused by microscopic “stones” that are present on the ends of hair follicles in the ear canal and that help you maintain your balance. Vertigo occurs when these stones break off and move from the body of the inner ear into its semicircular canals, which determine our perception of three-dimensional space. This usually occurs as a result of aging or head trauma. Free-floating stones cause the inner ear to give faulty information to the brain about our position in space, creating a false sensation of motion. The mechanism of B.P.P.V. was discovered almost a century ago by the Viennese physician Dr. Robert Bárány, who won a Nobel Prize for his work. In 1979, Dr. John Epley, an ear, nose and throat specialist in Portland, Ore., found that a simple maneuver could treat most cases of B.P.P.V. without the need for drugs or surgery. The Epley maneuver is a series of rapid changes in position of the head that are performed in a doctor’s office. The maneuver repositions stones so they do not cause symptoms. Incidentally, B.P.P.V. has been reported to be cured in some people after they have ridden on roller coasters. © 2019 The New York Times Company

Related chapters from BN: Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 26365 - Posted: 06.28.2019

By Lindsey Bever Doctors had broken the disheartening news to Rachel Palma, explaining that the lesion on her brain was suspected to be a tumor, and her scans suggested that it was cancerous. Palma, a newlywed entering a new chapter in her life, said she was in shock, unwilling to believe it was true. In September, scrubbed-up surgeons in an operating room at Mount Sinai Hospital in New York City opened Palma’s cranium and steeled themselves for a malignant brain tumor, said Jonathan Rasouli, chief neurosurgery resident at the Icahn School of Medicine at Mount Sinai. But instead, Rasouli said, they saw an encapsulated mass resembling a quail egg. “We were all saying, ‘What is this?’ ” Rasouli recalled Thursday in a phone interview with The Washington Post. “It was very shocking. We were scratching our heads, surprised at what it looked like.” The surgeons removed it from Palma’s brain and placed it under a microscope to get a closer look. Then they sliced into it — and found a baby tapeworm. Palma, from Middletown, N.Y., said she had mixed emotions about it. “Of course I was grossed out,” the 42-year-old said Thursday, explaining that no one wants to think there’s a tapeworm growing inside an egg in his or her brain. “But of course, I was also relieved. It meant that no further treatment was necessary.” A scan showing the tapeworm in Rachel Palma's brain. (Mount Sinai Health System) © 1996-2019 The Washington Post

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 26308 - Posted: 06.07.2019

By Diana Kwon Few things are more refreshing than enjoying a cool beverage after spending a day under the hot summer sun. But gulping down a drink does not always quench thirst. Seawater, for example, may look appealing to someone stranded in the middle of the ocean, but taking a swig of it will only worsen dehydration. Scientists have now discovered that in rodents, signals from both the throat and gut control feelings of thirst. These distinct pathways may explain why consuming a beverage is typically refreshing but does not always sate one’s thirst, according to a study by Yuki Oka, a neuroscientist at the California Institute of Technology, and his colleagues at the California Institute of Technology, published May 29 in Neuron. Last year, Oka’s team reported that the simple act of gulping activated a circuit in the lamina terminalis, a region near the front of the brain, which ultimately led to the suppression of activity in neurons responsible for generating feelings of thirst. This throat-brain pathway, which the researchers identified in mice, switched on regardless of what an animal consumed—water, saline solution and oil produced similar effects. But the fact that all of these substances were able to inhibit the brain’s “thirst” neurons indicated that there was something missing. After all, if any liquid could satisfy an animal’s thirst, it might not consume enough water to remain hydrated. According to Oka, behavioral studies in animals dating back decades suggested that there was an additional mechanism in the gut that signaled the presence of water to the brain. So in their latest investigation, Oka’s team set out to map the brain circuits responsible for receiving these signals. By injecting fluids directly into the guts of mice, the researchers discovered that in order for the rodents to feel fully hydrated, this second gut-based circuit needed to be activated. Without these gastrointestinal signals—which, unlike ones from the throat, selectively responded to the presence of water—the brain’s “thirst” neurons quickly revved up again, driving the animals to drink more. © 2019 Scientific American

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 26280 - Posted: 05.30.2019

By C. Claiborne Ray Q. Humans can’t drink seawater. So what do sea lions, whales, dolphins and sea birds drink? A. Marine animals may consume both freshwater and saltwater. They rely on various adaptations for survival when only saltwater is available. Many marine mammals have specialized organs called reniculate kidneys with multiple lobes, increasing their urine-concentrating efficiency beyond that of humans. These animals can handle high concentrations of salt in seawater without becoming dehydrated by salt buildup, as humans would. Experts now believe, however, that many of these creatures drink seawater only occasionally. Instead they get low-salt water from what they eat or manage to produce it on their own. Whales, for example, have the specialized kidneys but need far less water than land mammals. Whales get water mostly from the small sea creatures, like krill, that form much of their diet. Seabirds, on the other hand, have special organs called salt glands above their eyes that extract excess salt from the bloodstream and excrete it through the nostrils. © 2019 The New York Times Company

Related chapters from BN: Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 26273 - Posted: 05.29.2019

By Joe Lindsey In the final episode of Season 7 of Game of Thrones, the Night King uses a terrifying weapon—the recently deceased dragon Viserion, now reanimated—to destroy the massive, magic-infused Wall that has for millennia stopped the White Walkers from invading Westeros. As the Army of the Dead lumbers through the gap, it’s pretty clear: Winter is here. We’ve only seen the Army of the Dead in action a few times now: Hardhome, in Season 5, and Season 7’s epic Wight Hunt, but it seems like Episode 3 of Game of Thrones’ final season is setting us up for an absolutely titanic clash at the Stark’s ancestral home of Winterfell. But wights—or zombies to use a more common parlance—aren’t just a well-worn trope for fantasy writers. The possibility of reanimating dead tissue—including braaaaains—has challenged neurobiologists around the world. So what are the wights, how do they work, and why does an entire army psychically linked together seem to be controlled by just one mind—the Night King? First off, are wights zombies at all? There are actually two types of zombies, the shambling dead—as representing George A. Romero’s classics—and the zombies of Haitian legend. “There’s the socio-cultural definition of zombie from tales in Haitian voodoo, where someone was put into a state similar to death and then ‘brought back to life,’” says Bradley Voytek, avid Game of Thrones fan, neuroscientist at the University of California-San Diego, and co-author of Do Zombies Dream of Undead Sheep, which uses zombies as the basis for an introduction to serious neuroscience. ©2019 Hearst Magazine Media, Inc.

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook
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Link ID: 26175 - Posted: 04.27.2019

Jon Hamilton When you're thirsty, a swig of fresh water brings instant relief. But gulp down some salty sea water and you'll still feel parched. That's because your brain is trying to keep the concentration of salt in your body within a very narrow range, says Zachary Knight, an associate professor in physiology at the University of California, San Francisco and an investigator with the Howard Hughes Medical Institute. "If you experience, for example, a 10 percent change, you would be very sick," he says. "A 20 percent change and you could die." Knight and a team of researchers wanted to know how the brain keeps that from happening. They report the results of their search in an article published Wednesday in the journal Nature. "There has to be a mechanism for the brain to track how salty the solutions that you drink are and use that to fine-tune thirst," Knight says. "But the mechanism was unknown." So Knight's team began studying brain cells known as thirst neurons. First, the team piped fresh water directly into the stomachs of some thirsty mice. "Within a minute or two, infusing water into the stomach rapidly turns off these thirst neurons in the brain," says Chris Zimmerman, a graduate student in Knight's lab who conducted the experiment. "And not only that," Zimmerman says, "if we give [the mouse] access to water it doesn't drink at all." © 2019 npr

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Link ID: 26086 - Posted: 03.28.2019