How anesthesia affects your brain and body

Since 1846, doctors have used a variety of drugs to make patients unconscious for surgery, but even though the medications have changed, there’s one thing that remains the same- it works. But how exactly? We don’t know every detail about what’s going on when we administer anesthesia, but then again, we also don’t know exactly how consciousness works either. Following is a transcript of the video.

Narrator: When you go to sleep, if I pinched you, you’d be up. If I shook you, you’d be up, right? But under anesthesia, I’m gonna pinch you and do a full operation and you’re not up. So it’s really further on the spectrum of unconsciousness.

Narrator: When you wake up after being put under with general anesthesia you barely feel like any time has passed. You could have been out for an hour or a day and you wouldn’t know the difference.

Fong: When you go to a natural sleep, people call your name, your alarm goes off, you wake up, right? This is not what is gonna happen during general anesthesia. You’re gonna be unconscious.

Narrator: You’re closer to being in a coma than being asleep.

Anesthesia was first used during surgery in 1846. The drug provided at that time was ether. Now anesthesiologists more commonly use a combination of drugs like propofol and fentanyl which interrupt neural pathways so you don’t feel pain and you don’t remember the surgery.

Fong: Three things that you need for general anesthesia are you need amnesia so that they don’t remember, analgesia so they have pain relief and then operating conditions for the surgeon. Some surgeries you need the patient to be very relaxed so you would use a muscle relaxant. Other surgeries the patient just needs to be asleep and anesthetized but they don’t need relaxation so how they do that varies upon the different medications that you’re using. Some will depress excitatory neurons and some will enhance inhibitory neurons.

Narrator: Excitatory neurons, for example, get excited and send signals to other neurons to fire. Depressing them means less signals telling your brain you’re in pain. Inhibitory neurons do the opposite. They make it harder for neurons to generate these electrical signals. In either case this means fewer active neurons overall which is important because when your body is being poked and prodded, neurons would typically fire to tell your brain you’re in pain. If those neurons aren’t firing, your brain doesn’t know that your body is, well, being cut open.

Fong: Basically it interrupts the pathways and the communication between your neural networks. We’re aiming for them to be not in pain by looking at their vital signs, their heart rate, their blood pressure. Then we want to make sure that they’re unconscious.

Narrator: Without anesthesia, many important surgeries wouldn’t be possible because they’d be way too traumatic.

Fong: Surgery didn’t move forward, really, until anesthesia moved forward. You know, you watch those old movies. They give you a swig of alcohol, they put a tourniquet and they hack your leg off. People don’t do well with that, right? If you had a bad heart, that would be the end of that.

Narrator: After the procedure is complete the doctors stop administering the meds and the most powerful effects of the drugs wear off but even though you’re conscious again you might continue to experience some of the drugs side effects.

EDITOR’S NOTE: This video was originally published in August 2018.

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Daylight-saving time is literally killing us – it’s time to end this switch

clocks daylight saving
Daylight-saving time begins at 2 a.m. on Sunday, March 14.

Daylight-saving time is a killer.

The annual ritual in which we “gain” an hour of evening light in the summertime by pushing the clocks forward one hour each spring may seem like a harmless shift.

But every year on the Monday after the switch, hospitals report a 24% spike in heart-attack visits around the US.

Just a coincidence? Probably not. Doctors see an opposite trend each fall: The day after we turn back the clocks, heart attack visits drop 21% as many people enjoy a little extra pillow time.

“That’s how fragile and susceptible your body is to even just one hour of lost sleep,” sleep expert Matthew Walker, author of “How We Sleep,” previously told Insider.

daylight saving time March 2021 4x3

The reason that springing the clocks forward can kill us comes down to interrupted sleep schedules. This Sunday, March 14, instead of the clock turning from 1:59 to 2:00 a.m. as usual, it will tick forward to 3:00 a.m.

For those of us who will be asleep in bed, researchers estimate we’ll all deprive ourselves of an extra 40 minutes of sleep because of the clock change. And night-shift workers will get paid only for the seven hours of work they completed instead of their usual eight-hour paycheck, according to federal law.

Over the long haul, the interrupted sleep schedules that result from shifting the clocks back and forth twice a year may be bad for our health. Our bodies may not fully recover from the shift for weeks, though the tragic heart attack trend only lasts about a day.

We’re also prone to make more deadly mistakes on the roads: Researchers estimate that car crashes in the US caused by sleepy daylight-saving drivers likely cost 30 extra people their lives over the nine-year period from 2002-2011. The problems don’t stop there. DST also causes more reports of injuries at work, more strokes, and may lead to a temporary increase in suicides.

Walker said daylight-saving time, or DST, is a kind of “global experiment” we perform twice a year. And the results show just how sensitive our bodies are to the whims of changing schedules: In the fall the shift is a blessing; in the spring it’s a fatal curse.

Why we ‘save’ daylight for the later hours of the day

Daylight-saving time was originally concocted as a way to save energy in the evening, and was implemented during World War I in Germany. But more recent research suggests it’s probably not saving us any megawatts of power at all. There is some evidence, however, that extra evening light can reduce crime and increase the time people spend exercising, at least in certain climates.

Hawaii, North Shore of Oahu, Beach, Sunset

Worldwide, fewer than half of all countries participate in this biannual clock-changing ritual.

Not everyone in the US follows it either. Hawaii and Arizona ignore DST, since it makes less sense to shift the clocks when you live near the equator, where the sun rises and sets at roughly the same time every day.

Residents and lawmakers in California and Florida are also trying to ditch the switch. Voters in the Golden State opted to get rid of the annual clock change in the 2018 midterm elections, and Florida lawmakers enacted the “Sunshine Protection Act” that March, aimed at doing the same thing.

Thirteen more states have angled to move to year-round DST since then, with proposed legislation. But the shift to a permanent daylight-saving-time plan isn’t something states can decide for themselves: The measures require a green light from Congress to take effect, something both California and Florida, as well as the others (Arkansas, Delaware, Georgia, Idaho, Louisiana, Maine, Ohio, Oregon, South Carolina, Tennessee, Utah, Washington, and Wyoming) have yet to receive.

This year, some lawmakers are pushing to ditch the switch nationwide. A bipartisan group of eight US Senators reintroduced a bill earlier this week that would make Daylight Saving Time permanent across the entire US. GOP Sen. Marco Rubio of Florida, who introduced the bill, tweeted that the current biannual time change is “senseless.”

“More daylight in the evenings results in fewer car accidents & robberies,” Rubio added. “And it allows kids to play outside longer. #LockTheClock

But for now, the tradition inevitably costs some their lives. So while you might enjoy seeing a little more evening light next week, be extra-careful with your heart – and out on the road, too.

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Everything you need to know about Neuralink, Elon Musk’s company that wants to put microchips in people’s brains

Elon Musk
Elon Musk.

  • Neuralink is one of Elon Musk’s strange and futuristic portfolio of companies.
  • It’s developing neural interface technology — a.k.a. putting microchips into people’s brains.
  • The technology could help study and treat neurological disorders. 
  • Visit the Business section of Insider for more stories.

Tesla billionaire Elon Musk is known for high-profile companies like Tesla and SpaceX, but the billionaire also has a handful of unusual ventures. One them, he says, he started to one day achieve “symbiosis” between the human brain and artificial intelligence.

Neuralink is Musk’s neural interface technology company. Simply put, it is building technology that could be embedded in a person’s brain, where it could both record brain activity and potentially stimulate it.

While Musk likes to talk up his futuristic vision for the technology, merging human consciousness with AI, the tech has plenty of near-term potential medical applications such as the treatment of Parkinson’s disease.

Here’s everything you need to know about Neuralink:

Neuralink was quietly founded under the radar in 2016.

Although Musk has touted the near-term applications of Neuralink, he often links the company up with his fears about artificial intelligence. Musk has said that he thinks humanity will be able to achieve a “symbiosis” with artificial intelligence.

Musk told “Artificial Intelligence” podcast host Lex Fridman in 2019 that Neuralink was “intended to address the existential risk associated with digital superintelligence.”

“We will not be able to be smarter than a digital supercomputer, so, therefore, if you cannot beat ’em, join ’em,” Musk added.

Musk has made lots of fanciful claims about the enhanced abilities Neuralink could confer. In 2020 Musk said people would “save and replay memories” like in “Black Mirror,” or telepathically summon their car.

Experts have expressed doubts about these claims. 

In September 2020, Insider spoke to neuroscientist Prof. Andrew Jackson of the University of Newcastle. He said: “Not to say that that won’t happen, but I think that the underlying neuroscience is much more shaky.”

He added: “We understand much less about how those processes work in the brain, and just because you can predict the position of the pig’s leg when it’s walking on a treadmill, that doesn’t then automatically mean you’ll be able to read thoughts.”

Another professor, Andrew Hires, told Insider in August 2020 that Musk’s claims about merging with AI is where he goes off into “aspirational fantasy land.”

Neuralink is developing two bits of equipment. The first is a chip that would be implanted in a person’s skull, with electrodes fanning out into their brain.

Neuralink chip
The chip sits behind the ear, while electrodes are threaded into the brain.

The chip Neuralink is developing is about the size of a coin, and would be embedded in a patients’ skull. From the chip an array of tiny wires, each roughly 20 times thinner than a human hair, fan out into the patient’s brain.

The wires are equipped with 1,024 electrodes which are able to both monitor brain activity  and, theoretically, electrically stimulate the brain. This data is all transmitted wirelessly via the chip to computers where it can be studied by researchers.

 

The second is a robot that could automatically implant the chip.

Neuralink surgical robot
Neuralink surgical robot.

The robot would work by using a stiff needle to punch the flexible wires emanating from a Neuralink chip into a person’s brain, a bit like a sewing machine.

Neuralink released a video showcasing the robot in January 2021.

 

Musk has claimed the machine could make implanting Neuralink’s electrodes as easy as LASIK eye surgery. While this is a bold claim, neuroscientists previously told Insider in 2019 that the machine has some very promising features.

Professor Andrew Hires highlighted a feature, which would automatically adjust the needle to compensate for the movement of a patient’s brain, as the brain moves during surgery along with a person’s breathing and heartbeat.

The robot as it currently stands is eight feet tall, and while Neuralink is developing its underlying technology its design was crafted by Woke Studios.

In 2020, the company showed off one of its chips working in a pig named Gertrude during a live demo.

Gertrude Neuralink
The Neuralink device in Gertrude’s brain transmitted data live during the demo as she snuffled around.

The demonstration was proof of concept, and showed how the chip was able to accurately predict the positioning of Gertrude’s limbs when she was walking on a treadmill, as well as recording neural activity when the pig snuffled about for food. Musk said the pig had been living with the chip embedded in her skull for two months.

 

“In terms of their technology, 1,024 channels is not that impressive these days, but the electronics to relay them wirelessly is state-of-the-art, and the robotic implantation is nice,” said Professor Andrew Jackson, an expert in neural interfaces at Newcastle University.

“This is solid engineering but mediocre neuroscience,” he said.

Jackson told Insider following the 2020 presentation that the wireless relay from the Neuralink chip could potentially have a big impact on the welfare of animal test subjects in science, as most neural interfaces currently in use on test animals involve wires poking out through the skin.

“Even if the technology doesn’t do anything more than we’re able to do at the moment — in terms of number of channels or whatever — just from a welfare aspect for the animals, I think if you can do experiments with something that doesn’t involve wires coming through the skin, that’s going to improve the welfare of animals,” he said.

Although none of the tech Neuralink has showcased so far has been particularly groundbreaking, neuroscientists are impressed with how well it’s been able to bundle up existing technologies.

Elon Musk Neuralink pigs
Elon Musk presenting during the 2020 demo.

“All the technology that he showed has been already developed in some way or form, […] Essentially what they’ve done is just package it into a nice little form that then sends data wirelessly,” Dr. Jason Shepherd, an associate professor of neurobiology at the University of Utah, told Insider following the 2020 demonstration.

“If you just watched this presentation, you would think that it’s coming out of nowhere, that Musk is doing this magic, but in reality, he’s really copied and pasted a lot of work from many, many labs that have been working on this,” he added.

Elon Musk has boasted multiple times that the company has put the chip in a monkey, though neuroscientists aren’t that blown away by this.

squirrel monkey
Not pictured: the monkey Neuralink has implanted a microchip into.

Elon Musk excitedly announced in Neuralink’s 2019 presentation that the company had successfully implanted its chip into a monkey. “A monkey has been able to control a computer with its brain, just FYI,” he said, which appeared to take Neuralink president Max Hodak by surprise. “I didn’t realize we were running that result today, but there it goes,” said Hodak.

Musk re-iterated the claim in February 2021 with a little extra detail. 

“We’ve already got a monkey with a wireless implant in their skull, and the tiny wires, who can play video games using his mind,” Musk said during a long and wide-ranging interview on Clubhouse.

 Neuroscientists speaking to Insider in 2019 said that while the claim might grab the attention of readers, they did not find it surprising or even particularly impressive.

“The monkey is not surfing the internet. The monkey is probably moving a cursor to move a little ball to try to match a target,”said Professor Andrew Hires, an assistant professor of neurobiology at the University of California.

Implanting primates with neural-brain interfaces that allow them to control objects on screens has been done before, and is expected in any research that aims to one day implant technology into human brains.

Elon Musk has said human testing could start by the end of this year, but he also said that last year.

Elon Musk

Elon Musk said during an appearance on the “Joe Rogan Experience” podcast in May 2020 that Neuralink could begin testing on human subjects within a year. He made the same claim during an interview on Clubhouse in February 2021.

Previously in 2019 Musk said the company hoped to get a chip into a human patient by the end of 2020.

Experts voiced doubt about this timeline at the time, as part of safety testing a neural interface device involves implanting it in an animal test subject (normally a primate) and leaving it there for an extended amount of time to test its longevity — as any chip would have to stay in a human patient’s brain for a lifetime.

“You can’t accelerate that process. You just have to wait — and see how long the electrodes last. And if the goal is for these to last decades, it’s hard to imagine how you’re going to be able to test this without waiting long periods of time to see how well the devices perform,” Jacob Robinson, a neuroengineer at Rice University, told STAT News in 2019.

 

 

In the near-term, the uses of a chip in someone’s brain could be to treat neurological disorders like Parkinson’s.

Neuralink
Close-up footage of the needle on Neuralink’s brain surgery robot.

Improved neural interface technology like Neuralink’s could be used to better study and treat severe neurological conditions such as Parkinson’s and Alzheimer’s.

Prof. Andrew Hires told Insider another application could be allowing people to control robotic prostheses with their minds.

“The first application you can imagine is better mental control for a robotic arm for someone who’s paralyzed,” Hires said in a 2019 interview with Insider, saying that the electrodes in a patient’s brain could potentially reproduce the sensation of touch, allowing the patient to exert finer motor control over a prosthetic limb.

Elon Musk also says in the long-term the chip could be used to meld human consciousness with artificial intelligence – though experts are skeptical of this.

Elon Musk

Although Musk has touted the near-term applications of Neuralink, he often links the company up with his fears about artificial intelligence. Musk has said that he thinks humanity will be able to achieve “symbiosis with artificial intelligence” through 

Musk told “Artificial Intelligence” podcast host Lex Fridman in 2019 that Neuralink was “intended to address the existential risk associated with digital superintelligence.”

“We will not be able to be smarter than a digital supercomputer, so, therefore, if you cannot beat ’em, join ’em,” Musk added.

Musk has made lots of fanciful claims about the enhanced abilities Neuralink could confer. In 2020 Musk said people would “save and replay memories” like in “Black Mirror,” or telepathically summon their car.

Experts have expressed doubts about these claims. 

“Not to say that that won’t happen, but I think that the underlying neuroscience is much more shaky. We understand much less about how those processes work in the brain, and just because you can predict the position of the pig’s leg when it’s walking on a treadmill, that doesn’t then automatically mean you’ll be able to read thoughts,” said Prof. Andrew Jackson.

In 2019 Prof. Andrew Hires said Musk’s claims about merging with AI is where he goes off into “aspirational fantasy land.”

Musk’s also made dubious claims about its medical applications. At one point he also claimed the technology could “solve autism.”

During an appearance on the “Artificial Intelligence” podcast with Lex Fridman in November 2019, Elon Musk said Neuralink could in future “solve a lot of brain-related diseases,” and named autism and schizophrenia as examples.

Autism is classified as a developmental disorder, not a disease, and the World Health Organization describes schizophrenia as a mental disorder.

One neuroscientist told Insider there are big ethical problems with the idea of performing brain surgery for anything other than essential treatment.

Dr. Rylie Green of Imperial College London told Insider in 2019 that the notion of performing brain surgery on a healthy person is deeply troubling.

“To get any of these devices into your brain […] is very, very high-risk surgery,” she said. “People do it because they have severe limitations and there is a potential there to improve their life. Doing it for fun is not a great idea,” she added.

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