Emery N. Brown, M.D., Ph.D.

New research addresses a gap in understanding how ketamine’s impact on individual neurons leads to pervasive and profound changes in brain network function.

Ketamine, a World Health Organization Essential Medicine, is widely used at varying doses for sedation, pain control, general anesthesia, and as a therapy for treatment-resistant depression. While scientists know its target in brain cells and have observed how it affects brain-wide activity, they haven’t known entirely how the two are connected. A new study by a research team spanning four Boston-area institutions uses computational modeling of previously unappreciated physiological details to fill that gap and offer new insights into how ketamine works.

“This modeling work has helped decipher likely mechanisms through which ketamine produces altered arousal states as well as its therapeutic benefits for treating depression,” says co-senior author Emery N. Brown, the Edward Hood Taplin Professor of Computational Neuroscience and Medical Engineering at The Picower Institute for Learning and Memory at MIT, as well as an anesthesiologist at Massachusetts General Hospital and a professor at Harvard Medical School… Continue reading.

An advanced closed-loop anesthesia delivery system that monitors brain state to tailor propofol dose and achieve exactly the desired level of unconsciousness could reduce post-op side effects.

If anesthesiologists had a rigorous means to manage dosing, they could deliver less medicine, maintaining exactly the right depth of unconsciousness while reducing postoperative cognitive side effects in vulnerable groups like the elderly. But with myriad responsibilities for keeping anesthetized patients alive and stable as well as maintaining their profoundly unconscious state, anesthesiologists don’t have the time without the technology.

To solve the problem, researchers at The Picower Institute for Learning and Memory at MIT and Massachusetts General Hospital (MGH) have invented a closed-loop system based on brain state monitoring that accurately controls unconsciousness by automating doses of the anesthetic drug propofol every 20 seconds… Continue reading.

Distinctive EEG patterns indicate when a patient’s state of unconsciousness under general anesthesia is more profound than necessary.

When patients undergo general anesthesia, their brain activity often slows down as they sink into unconsciousness. Higher doses of anesthetic drugs can induce an even deeper state of unconsciousness known as burst suppression, which is associated with cognitive impairments after the patient wakes up.

A new study from MIT, in which the researchers analyzed the EEG patterns of patients under anesthesia, has revealed brain wave signatures that could help anesthesiologists determine when patients are transitioning into that deeper state of unconsciousness. This could enable them to prevent patients from falling into that state, reducing the risk of postoperative brain dysfunction… Continue reading.

Scientists hypothesize that, as in a hibernating turtle, the brain under sedation and deprived of oxygen may assume a protective state.

Many Covid-19 patients who have been treated for weeks or months with mechanical ventilation have been slow to regain consciousness even after being taken off sedation. A new article in the Proceedings of the National Academy of Sciences offers the hypothesis that this peculiar response could be the effect of a hibernation-like state invoked by the brain to protect cells from injury when oxygen is scarce.

A very similar kind of state, characterized by the same signature change of brain rhythms, is not only observed in cardiac arrest patients treated by chilling their body temperature, a method called “hypothermia,” but also by the painted turtle, which has evolved a form of self-sedation to contend with long periods of oxygen deprivation, or “anoxia,” when it overwinters underwater… Continue reading.

A new study by researchers at MIT and Massachusetts General Hospital (MGH) suggests the day may be approaching when advanced artificial intelligence systems could assist anesthesiologists in the operating room.

In a special edition of Artificial Intelligence in Medicine, the team of neuroscientists, engineers, and physicians demonstrated a machine learning algorithm for continuously automating dosing of the anesthetic drug propofol. Using an application of deep reinforcement learning, in which the software’s neural networks simultaneously learned how its dosing choices maintain unconsciousness and how to critique the efficacy of its own actions, the algorithm outperformed more traditional software in sophisticated, physiology-based simulations of patients. It also closely matched the performance of real anesthesiologists when showing what it would do to maintain unconsciousness given recorded data from nine real surgeries… Continue reading.

By developing the first statistical model to finely characterize how ketamine anesthesia affects the brain, a team of researchers at MIT’s Picower Institute for Learning and Memory and Massachusetts General Hospital have laid new groundwork for three advances: understanding how ketamine induces anesthesia; monitoring the unconsciousness of patients in surgery; and applying a new method of analyzing brain activity.

Based on brain rhythm measurements from nine human and two animal subjects, the new model published in PLOS Computational Biology defines the distinct, characteristic states of brain activity that occur during ketamine-induced anesthesia, including how long each lasts. It also tracks patterns of how the states switch from one to the next. The “beta-hidden Markov model” therefore provides anesthesiologists, neuroscientists, and data scientists alike with a principled guide to how ketamine anesthesia affects the brain and what patients will experience… Continue reading.

Carnegie Mellon University will award the Dickson Prize in Science to Dr. Emery N. Brown, an esteemed anesthesiologist, neuroscientist and statistician. He is the Edward Taplin Professor of Medical Engineering and Computational Neuroscience at Massachusetts Institute of Technology , the Warren M. Zapol Professor of Anesthesia at Harvard Medical School and a practicing anesthesiologist at Massachusetts General Hospital.

Brown will deliver the Dickson Prize Lecture, “The Dynamics of the Unconscious Brain Under General Anesthesia,” and receive a medal and cash prize at 4:30 p.m., Thursday, Jan. 31, in the Tepper Building’s Simmons Auditorium A. The event is free and open to the public.

“My goal is to provide every patient requiring surgery precisely controlled, side-effect free general anesthesia… Continue reading.

People sometimes mistakenly think of general anesthesia as just a really deep sleep, but in fact, anesthesia is really four brain states — unconsciousness, amnesia, immobility, and suppression of the body’s damage sensing response, or “nociception.” In a new paper in Anesthesia and Analgesia, MIT neuroscientist and statistician Emery N. Brown and his colleagues argue that by putting nociception at the top of the priority list and taking a principled neuroscientific approach to choosing which drugs to administer, anesthesiologists can use far less medication overall, producing substantial benefits for patients.

“We’ve come up with strategies that allow us to dose the same drugs that are generally used but in different proportions that allow us to achieve an anesthetic state that is much more desirable,” says Brown, the Edward Hood Taplin Professor of Computational Neuroscience and Health Sciences and Technology in the Picower Institute for Learning and Memory at MIT and a practicing anesthesiologist at Massachusetts General Hospital… Continue reading.

It’s intuitive that anesthesia operates in the brain, but the standard protocol among anesthesiologists when monitoring and dosing patients during surgery is to rely on indirect signs of arousal such as movement, and changes in heart rate and blood pressure. Through research in brain science and statistical modeling, Emery N. Brown, an anesthesiologist at Massachusetts General Hospital and neuroscientist at MIT’s Picower Institute for Learning and Memory, is putting the brain at the center of the field.

His findings allow him to safely give less anesthesia, for example, which can have important benefits for patients.

The key has been to develop a theoretical (i.e. neuroscientific) and analytical (i.e. statistical) understanding of electroencephalogram (EEG) brain wave measurements of patients under general anesthesia. In a presentation at the annual meeting of the American Association for the Advancement of Science in Austin, Texas, on Feb. 16, Brown described how anesthesia’s effects in the brain produce specific patterns of brain waves and how monitoring them via EEG data can lead to better care. He spoke as part of a broader discussion on the use of data analysis in brain research… Continue reading.

Emery Brown, anesthesiologist, Professor of Computational Neuroscience at MIT, and Co-Director of the Harvard-MIT Division of Health Sciences and Technology, unveiled the surprising truth about exactly what happens to your brain under anesthesia and what it suggests for understanding the brain and improving treatment.

“Anesthesia works primarily through the production of oscillations that disrupt the way regions in the brain communicate.” Emery Brown at TEDMED 2014

What motivated you to speak at TEDMED?

When I had the honor to be invited, I realized that it would be a great opportunity to educate the public on general anesthesia and other practices in anesthesiology. The state of general anesthesia is viewed as a blackbox process by the field of anesthesiology, other fields of medicine and the general public. I was motivated by the importance of bringing an informed, modern perspective on general anesthesia to the lay public, the medical field, neuroscientists and anesthesiologists.

Brain injury patients are sometimes deliberately placed in a coma with anesthesia drugs to allow swelling to go down and their brains to heal. Comas can last for days, during which patients’ brain activity must be regularly monitored to ensure the right level of sedation. The constant checking is “totally inefficient,” says Emery Brown, an anesthesiologist at Massachusetts General Hospital (MGH) and a professor in MIT’s Department of Brain and Cognitive Sciences. Brown and his colleagues at MGH have developed a “brain-machine interface” that automatically monitors brain activity and adjusts drug dosages accordingly. They’ve tested the system on rats and are now planning human trials.

Study reveals brain patterns produced by a general anesthesia drug; work could help doctors better monitor patients.

Since the mid-1800s, doctors have used drugs to induce general anesthesia in patients undergoing surgery. Despite their widespread use, little is known about how these drugs create such a profound loss of consciousness.

In a new study that tracked brain activity in human volunteers over a two-hour period as they lost and regained consciousness, researchers from MIT and Massachusetts General Hospital (MGH) have identified distinctive brain patterns associated with different stages of general anesthesia. The findings shed light on how one commonly used anesthesia drug exerts its effects, and could help doctors better monitor patients during surgery and prevent rare cases of patients waking up during operations.

Anesthesiologists now rely on a monitoring system that takes electroencephalogram (EEG) information and combines it into a single number between zero and 100. However, that index actually obscures the information that would be most useful, according to the authors of the new study, which appears in the Proceedings of the National Academy of Sciences the week of March 4.

“When anesthesiologists are taking care of someone in the operating room, they can use the information in this article to make sure that someone is unconscious, and they can have a specific idea of when the person may be regaining consciousness,” says senior author Emery Brown, an MIT professor of brain and cognitive sciences and health sciences and technology and an anesthesiologist at MGH.

Obama invites Boyden, Brown, Desimone and Seung to launch of new federal initiative.

Four MIT neuroscientists were among those invited to the White House on Tuesday, April 2, when President Barack Obama announced a new initiative to understand the human brain.

Professors Ed Boyden, Emery Brown, Robert Desimone and Sebastian Seung were among a group of leading researchers who joined Obama for the announcement, along with Francis Collins, director of the National Institutes of Health, and representatives of federal and private funders of neuroscience research.

Brown, Gore, Ploegh and Zhang receive grants for innovative biomedical research.

Four MIT faculty members have been awarded National Institutes of Health (NIH) grants designed to promote innovative biomedical research.

The Institute’s recipients of these new NIH grants are Hidde Ploegh, professor of biology and member of the Whitehead Institute; Feng Zhang, assistant professor of brain and cognitive sciences and member of the McGovern Institute; Jeff Gore, assistant professor of physics; and Emery Brown, professor of brain and cognitive sciences.

New model of neuro-electric activity could help scientists better understand quiescent brain states such as coma.

Different brain states produce different waves of electrical activity, with the alert brain, relaxed brain and sleeping brain producing easily distinguishable electroencephalogram (EEG) patterns. These patterns change even more dramatically when the brain goes into certain deeply quiescent states during general anesthesia or a coma.

MIT and Harvard University researchers have now figured out how one such quiescent state, known as burst suppression, arises. The finding, reported in the online edition of the Proceedings of the National Academy of Sciences the week of Feb. 6, could help researchers better monitor other states in which burst suppression occurs. For example, it is also seen in the brains of heart attack victims who are cooled to prevent brain damage due to oxygen deprivation, and in the brains of patients deliberately placed into a medical coma to treat a traumatic brain injury or intractable seizures.

During burst suppression, the brain is quiet for up to several seconds at a time, punctuated by short bursts of activity. Emery Brown, an MIT professor of brain and cognitive sciences and health sciences and technology and an anesthesiologist at Massachusetts General Hospital, set out to study burst suppression in the anesthetized brain and other brain states in hopes of discovering a fundamental mechanism for how the pattern arises. Such knowledge could help scientists figure out how much burst suppression is needed for optimal brain protection during induced hypothermia, when this state is created deliberately.

When patients awaken from surgery, they’re usually groggy and disoriented; it can take hours for a patient to become fully clearheaded again. Emery Brown, an MIT neuroscientist and an anesthesiologist at Massachusetts General Hospital (MGH), thinks it doesn’t have to be that way.

Brown and colleagues at MGH are studying the effects of stimulants that could be used to bring patients out of general anesthesia much faster. One potential candidate is Ritalin, the drug commonly used to treat attention deficit hyperactivity disorder (ADHD). In a study published online Sept. 20 in the journal Anesthesiology, the researchers show that giving anesthetized rats an injection of Ritalin brings them out of anesthesia almost immediately.

The National Institute of Statistical Sciences (NISS) has presented the 2011 Jerome Sacks Award for Cross-Disciplinary Research to Dr. Emery N. Brown of MIT and Harvard. Susan Ellenberg, chair of the Board of Trustees, announced the award at the 2011 Joint Statistical Meetings in Miami, Florida. The annual award, named in honor of Jerome (Jerry) Sacks, the founding director of NISS, was established in 2000 to recognize “sustained, high-quality cross-disciplinary research involving the statistical sciences.”

Dr. Emery Neal Brown, 54,  is a professor of anesthesiology at Harvard Medical School, a professor of computational neuroscience at M.I.T. and  a practicing physician, seeing patients at Massachusetts General Hospital. Between all that, he heads a laboratory seeking to unravel one of medicine’s big questions: how anesthesia works.

We spoke for three hours last month at his Massachusetts General office and more recently by telephone. An edited version of the two interviews follows.

Neuroscientist Emery Brown hopes to shed light on a longstanding medical mystery: how general anesthesia works.

Since 1846, when a Boston dentist named William Morton gave the first public demonstration of general anesthesia using ether, scientists and doctors have tried to figure out what happens to the brain during general anesthesia.

Though much has been learned since then, many aspects of general anesthesia remain a mystery. How do anesthetic drugs interfere with neurons and brain chemicals to produce the profound loss of consciousness and lack of pain typical of general anesthesia? And, how does general anesthesia differ from sleep or coma?

Emery Brown, an MIT neuroscientist and practicing anesthesiologist at Massachusetts General Hospital, wants to answer those questions by bringing the rigorous approach of neuroscience to the study of general anesthesia. In a review article published online Dec. 29 in the New England Journal of Medicine, he and two colleagues lay out a new framework for studying general anesthesia by relating it to what is already known about sleep and coma.