Debunking the "Bereitschaftspotential", the brain signal that seemed to kill off free will

A photo of the 1964 experiment documenting the Bereitschaftspotential

In 1964, a German experiment asked people to randomly tap their fingers -- whenever they wanted -- while having their brain's electrical activity monitored. The scientists discovered something nifty: The Bereitschaftspotential, a little burst of electrical activity the subjects' brains gave off in the milliseconds just before the finger-tap. Neuroscientists were fascinated: We now had a glimpse of the brain's crucial planning activities.

In the 80s, things got super weird. The American physiologist Benjamin Libet repeated the experiment and observed the Bereitschaftspotential occurring about 350 milliseconds before the subject decided to move their fingers. In other words, your brain and body were deciding to move your finger before you yourself were aware of your intent to do so. Free will was an illusion.

Armchair philosophers went to town on this, as you can imagine: Consciousness is an illusion! We're well and truly just self-deluding bags of meat! etc etc.

Then in 2012, Aaron Schurger -- a scientist at Paris' National Institute of Health and Medical Research -- proposed a different explanation for the Bereitschaftspotential. As he knew from his research, the brain is constantly a hive of activity and electrophysiological noise, and like any natural phenomenon with tons of little jittering components, it produces wave-like crests of activity.

So maybe the Bereitschaftspotential was just that. Maybe it was just the product of a noisy brain. A couple of top neuroscientists wondered if the original 1964 finger-tap experiment had been misinterpreted, and its correlations misunderstood. Since the decision to tap your finger randomly isn't terribly consequential, maybe the subjects were unconsciously timing their fingertaps with the Bereitschaftspotential. Read the rest

Johns Hopkins Medicine launches major center for psychedelic drug research

The esteemed research institute and medical school Johns Hopkins Medicine is starting the Center for Psychedelic and Consciousness Research thanks to $17 million in private donations. The generous funders include Boing Boing pal and author Tim Ferriss, WordPress founder Matt Mullenweg, TOMS shoes founder Blake Mycoskie, and investor Craig Nerenberg. Psychedelics have tremendous unlocked therapeutic potential for the likes of severe depression, PTSD, obsessive-compulsive disorder, and alcoholism, What a wonderful, important, and worthy cause these individuals chose to support. From Johns Hopkins Medical:

In 2000, the psychedelic research group at Johns Hopkins was the first to achieve regulatory approval in the U.S. to reinitiate research with psychedelics in healthy volunteers who had never used a psychedelic. Their 2006 publication on the safety and enduring positive effects of a single dose of psilocybin sparked a renewal of psychedelic research worldwide.

Since then, the researchers have published studies in more than 60 peer-reviewed journal articles. Their research has demonstrated therapeutic benefits for people who suffer from conditions including nicotine addiction and depression and anxiety caused by life-threatening diseases such as cancer. It has paved the way for current studies on treatment of major depressive disorder. These researchers have also expanded the field of psychedelic research by publishing safety guidelines that have helped gain approval for psychedelic studies at other universities around the world and by developing new ways of measuring mystical, emotional, and meditative experiences while under the influence of psychedelics.

The group's findings on both the promise and the risks of psilocybin in particular helped create a path forward for the chemical's potential medical approval and reclassification from a Schedule I drug, the most restrictive federal government category, to a more appropriate level.

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A deep dive into how parasites hijack our behavior and how we evolved to resist them

On Slate Star Codex (previously), Scott Alexander breaks down Invisible Designers: Brain Evolution Through the Lens of Parasite Manipulation, Marco Del Giudice's Quarterly Review of Biology paper that examines the measures that parasites take to influence their hosts' behaviors, and the countermeasures that hosts evolve to combat them. Read the rest

Scientists control mouse neurons so the rodents "see" things that aren't there

Scientists have used laser light to activate neurons in a mouse's brain so the rodents "sees" non-existent lines. The technique, called optogenetics, switches on and off neurons that have been previously genetically engineered to be light-sensitive. According to Science News, "the results, described online July 18 in Science, represent the first time scientists have created a specific visual perception with laboratory trickery." In this case, the mice had been trained to drink water from a spout upon seeing the lines. From Science News:

When optogenetics first debuted about 15 years ago, everyone was hoping to achieve this level of precise control over perception, and the behaviors that follow, says Karl Deisseroth, a neuroscientist and psychiatrist who pioneered the technique. “It’s exciting to get to this point,” says Deisseroth, a Howard Hughes Medical Institute investigator at Stanford University....

Similar approaches could let scientists create other sorts of perceptions, such as smells, touches and tastes, Deisseroth says.

Previously: "Scientists remote control a mouse with a wireless LED brain implant" Read the rest

Incredible ultra-high resolution 3D brain scan from 100 hour MRI

More than 100 hours of MIR scanning has generated an image of a whole human brain with unprecedented level of detail. Massachusetts General Hospital researchers and their colleagues used a 7 Tesla MRI machine, recently approved by the FDA, to scan the donated brain from a 58-year-old-woman. The image shows detail down to .1 millimeter. From Science News:

Before the scan began, researchers built a custom spheroid case of urethane that held the brain still and allowed interfering air bubbles to escape. Sturdily encased, the brain then went into a powerful MRI machine called a 7 Tesla, or 7T, and stayed there for almost five days of scanning...

Researchers can’t get the same kind of resolution on brains of living people. For starters, people couldn’t tolerate a 100-hour scan. And even tiny movements, such as those that come from breathing and blood flow, would blur the images...

These (new kinds of) detailed brain images could hold clues for researchers trying to pinpoint hard-to-see brain abnormalities involved in disorders such as comas and psychiatric conditions such as depression.

"7 Tesla MRI of the ex vivo human brain at 100 micron resolution" (bioRxiv.org) Read the rest

Humans have a sixth sense for Earth's magnetic field

A new study suggests that humans can subconsciously sense Earth's magnetic field. While this capability, called magnetoreception, is well known in birds and fish, there is now evidence that our brains are also sensitive to magnetic fields. The researchers from Caltech and the University of Tokyo measured the brainwaves of 26 participants who were exposed to magnetic fields that could be manipulated. Interestingly, the brainwaves were not affected by upward-pointing fields. From Science News:

Participants in this study, who all hailed from the Northern Hemisphere, should perceive downward-pointing magnetic fields as natural, whereas upward fields would constitute an anomaly, the researchers argue. Magnetoreceptive animals are known to shut off their internal compasses when encountering weird fields, such as those caused by lightning, which might lead the animals astray. Northern-born humans may similarly take their magnetic sense “offline” when faced with strange, upward-pointing fields...

Even accounting for which magnetic changes the brain picks up, researchers still don’t know what our minds might use that information for, (Caltech neurobiologist and geophysicist Joseph) Kirschvink says. Another lingering mystery is how, exactly, our brains detect Earth’s magnetic field. According to the researchers, the brain wave patterns uncovered in this study may be explained by sensory cells containing a magnetic mineral called magnetite, which has been found in magnetoreceptive trout as well as in the human brain.

"Transduction of the Geomagnetic Field as Evidenced from Alpha-band Activity in the Human Brain" (eNeuro)

"Evidence for a Human Geomagnetic Sense" (Caltech) Read the rest

Where does consciousness come from?

"Consciousness is what allows us to be aware of both our surroundings and our own inner state." In the first of a three part video series, "Kruzgesagt - In a Nutshell" examines "how unaware things come aware." Stay tuned for theories of consciousness that of course may be as much about philosophy as they are neuroscience.

Sources here.

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Sleep is a brain-repair mechanism, new study proves

Scientists Lior Appelbaum and David Zada in Israel publish new proof that sleep serves to help our brains repair damage. Read the rest

Scientific tips on how to cram for an exam

ASAP Science provides some excellent tips for intensive, last-minute studying of just about any subject where you need to remember a lot of information. The video covers a lot of ground, from memory palaces and cortisol to metacognition to other things I can't remember because I didn't study enough.

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Brain-zapping implants that change mood and lift depression

Teams of researchers are developing sesame seed-size neuro-implants that detect brain activity that signals depression and then deliver targeted electrical zaps to elevate your mood. It's very early days in the science and technology but recent studies suggest that we're on the path. Links to scientific papers below. Fortunately, the goal is to develop tools and a methodology more precise than the horrifically blunt "shock therapy" of last century. From Science News:

DARPA, a Department of Defense research agency, is funding (Massachusetts General Hospital's research on new brain stimulation methods) plus work at UCLA on targeted brain stimulation. Now in its fifth and final year, the (DARPA) project, called SUBNETS, aims to help veterans with major depression, post-traumatic stress, anxiety and other psychiatric problems. “It is extremely frustrating for patients to not know why they feel the way they do and to not be able to correct it,” Justin Sanchez, the director of DARPA’s Biological Technologies Office, said in a Nov. 30 statement. “We owe them and their families better options.”

These next-generation systems, primarily being developed at UCSF and Massachusetts General Hospital, might ultimately deliver. After detecting altered brain activity that signals a looming problem, these devices, called closed-loop stimulators, would intervene electrically with what their inventors hope is surgical precision.

In contrast to the UCSF group, Widge, who is at the University of Minnesota in Minneapolis, and his collaborators don’t focus explicitly on mood. The researchers want to avoid categorical diagnoses such as depression, which they argue can be imprecise.

Read the rest

The neuroscience of creativity (and yes, right brain/left brain is mostly bullshit)

Anna Abraham literally wrote the book on creativity and the brain. The Leeds Beckett University psychology professor is the author of a new textbook titled The Neuroscience of Creativity. From an interview with Abraham by psychologist Scott Barry Kaufman in Scientific American:

SBK: Why does the myth of the “creative right brain” still persist? Is there any truth at all to this myth?

AA: Like most persistent myths, even if some seed of truth was associated with the initial development of the idea, the claim so stated amounts to a lazy generalization and is incorrect. The brain’s right hemisphere is not a separate organ whose workings can be regarded in isolation from that of the left hemisphere in most human beings. It is also incorrect to conclude that the left brain is uncreative. In fact even the earliest scholars who explored the brain lateralization in relation to creativity emphasized the importance of both hemispheres. Indeed this is what was held to be unique about creativity compared to other highly lateralized psychological functions. In an era which saw the uncovering of the dominant involvement of one hemisphere over the other for many functions, and the left hemisphere received preeminent status for its crucial role in complex functions like language, a push against the tide by emphasizing the need to also recognize the importance of the right hemisphere for complex functions like creativity somehow got translated over time into the only ‘creative right brain’ meme. It is the sort of thing that routinely happens when crafting accessible sound bites to convey scientific findings.

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Why we never forget how to ride a bike

There's scientific truth to the saying that you never forget how to ride a bike. Even if you can't remember phone numbers, birthdays, or where the hell you parked your car, it's likely that even if you haven't been on a bicycle in decades, you can climb on and ride away just fine. Why? Neuropsychologist Boris Suchan of Germany's Ruhr University Bochum lays it out as best we know in Scientific American:

As it turns out, different types of memories are stored in distinct regions of our brains. Long-term memory is divided into two types: declarative and procedural.

There are two types of declarative memory: Recollections of experiences such as the day we started school and our first kiss are called episodic memory. This type of recall is our interpretation of an episode or event that occurred. Factual knowledge, on the other hand, such as the capital of France, is part of semantic memory. These two types of declarative memory content have one thing in common—you are aware of the knowledge and can communicate the memories to others.

Skills such as playing an instrument or riding a bicycle are, however, anchored in a separate system, called procedural memory. As its name implies, this type of memory is responsible for performance...

According to one idea, in the regions where movement patterns are anchored fewer new nerve cells may be formed in adults. Without this neurogenesis, or continuous remodeling in those regions, it’s less likely for those memories to get erased.

"Why Don’t We Forget How to Ride a Bike? Read the rest

The art (and science) of lying

Now seems like a fine time to read this Scientific American article titled The Art of Lying by Theodor Schaarschmidt. According to a study conducted by UC Santa Barbara psychologist Bella M. DePaulo and referenced in the article, people make up around two stories every day. Apparently, children "initially have difficulty formulating believable lies, but proficiency improves with age. Young adults between 18 and 29 do it best. After about the age of 45, we begin to lose this ability." From Scientific American:

Current thinking about the psychological processes involved in deception holds that people typically tell the truth more easily than they tell a lie and that lying requires far more cognitive resources. First, we must become aware of the truth; then we have to invent a plausible scenario that is consistent and does not contradict the observable facts. At the same time, we must suppress the truth so that we do not spill the beans—that is, we must engage in response inhibition. What is more, we must be able to assess accurately the reactions of the listener so that, if necessary, we can deftly produce adaptations to our original story line. And there is the ethical dimension, whereby we have to make a conscious decision to transgress a social norm. All this deciding and self-control implies that lying is managed by the prefrontal cortex—the region at the front of the brain responsible for executive control, which includes such processes as planning and regulating emotions and behavior.

"The Art of Lying" (Scientific American)

image: screenshot of Pinocchio film trailer, public domain Read the rest

Johns Hopkins researchers recommend reclassifying magic mushrooms from schedule I to IV drug

Based on a new study of the safety and abuse potential of psilocybin, the hallucinogenic drug in magic mushrooms, Johns Hopkins University School of Medicine researchers recommend that "psilocybin should be re-categorized from a schedule I drug—one with no known medical potential—to a schedule IV drug such as prescription sleep aids, but with tighter control." Read the rest

How to tell if a comatose patient is actually conscious

Neurologist Steven Laureys is an expert on the mysteries of consciousness. A researcher and clinician at the Belgian National Fund of Scientific Research he's known for testing comatose patients for any hidden signs of consciousness. From Scientific American's interview with Laureys:

So how is it possible to study something as complex as consciousness?

There are a number of ways to go about it, and the technology we have at our disposal is crucial in this regard. For example, without brain scanners we would know much, much less than we now do. We study the damaged brains of people who have at least partially lost consciousness. We examine what happens during deep sleep, when people temporarily lose consciousness. We’ve also been working with Buddhist monks because we know that meditation can trigger alterations in the brain; connections that are important in the networks involved in consciousness show changes in activity. Hypnosis and anesthesia can also teach us a great deal about consciousness. In Lige, surgeons routinely operate on patients under hypnosis ( including Queen Fabiola of Belgium). Just as under anesthesia, the connections between certain brain areas are less active under hypnosis. And finally, we are curious to understand what near-death experiences can tell us about consciousness. What does it mean that some people feel they are leaving their bodies, whereas others suddenly feel elated?

Patients are brought to Lige from all over Europe to undergo testing. How do you determine whether they are conscious?

Well, of course, the physician will say, “Squeeze my hand”—but this time while the patient is in a brain scanner.

Read the rest

You can hear the smile in someone's voice even when you can't

We often unconsciously mirror the behavior of people we interact with. This can include mirroring posture, gestures, and voice patterns. A recent paper in Current Biology reports that we can mirror a smile based on speech alone, and even do so without actually detecting the smile.

The researchers applied a signal processing technique for altering recorded speech under a neutral mouth position to what it would have sounded like had the speaker been smiling. They played 60 such recordings (some manipulated, some not) to 35 subjects, and asked them to judge whether the speaker was smiling. The researchers also measured the responses of two subject muscle groups while listening, the zygomatic (smiling) muscles and the corrugator (frowning) muscles.

When the subjects correctly reported neutral expression or smiling in the speech, both of their muscle groups accurately mirrored the speech while listening (e.g., for smiling speakers, zygomatic tensing and corrugator relaxing). Interestingly, even when the subjects were wrong, their zygomatic muscles still mirrored correctly. This was not true for the corrugators, which instead reflected the subjects' report.

Our mirroring capabilities go well beyond what we see, or even perceive. Read the rest

Teaching a banjo workshop while undergoing an EEG

Patrick Costello (previously) writes, "I had to go through a 25 hr EEG, but I didn't let the wires glued to my head stop me from posting my weekly frailing banjo workshop." Read the rest

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