How can researchers map something as complex as the human brain?
- Brain mapping is an attempt to identify the location of everything in the brain.
- An accurate map of the brain would immeasurably enhance our ability to understand how it works.
- The project is massive, involving multiple fields of biomedical research and expensive cutting-edge technology.
Brain mapping is one of the hottest current areas of research.
The brain is nothing short of amazing. Billions of neurons are in there — the current best guess is about 86 billion — and a roughly equal number of non-neuronal cells. The number of interconnections, or synapses, across which neurons communicate via chemical and electrical signals is believed to be about 125 trillion. There's a whole universe in there, even though the average adult brain weighs merely three pounds and measures just 140 mm x 167 mm x 93 mm.
Though we know a lot about the anatomy of the brain, its functions remain largely enigmatic. For instance, what is the biological mechanism that encodes memories? On a computer, files are encoded digitally with a series of ones and zeroes, a type of discrete storage. Cassette tapes are analog recordings, and information is stored magnetically. How does the brain store information? We don't know. Where consciousness is located in the brain — that is, the parts and functions that make us "us" — is likewise shrouded in mystery.
The challenge is described well by the journal Nature:
"Neuroscientists know frighteningly little about the brain's complexity. They have sketched out the broad anatomy of the brain, and realize that individual functions… are mediated by circuitry that crosses anatomical borders. They can examine the detailed electrical activity of small numbers of neurons. They can wield imaging technologies that show which brain areas are activated during defined tasks, such as viewing pleasant or unpleasant pictures. But those tiny (in brain terms) pieces of information have not led neuroscientists to the big picture: what we mean by human consciousness, what makes us our individual selves or why some people develop psychiatric disorders. Neuroscientists need to be able to join the dots — and there are a lot of dots."
As intimidating as this is, neuroscience is making incremental progress. We can correlate various actions and thoughts with brain activity. Scientists at Berkeley, for example, can tell what part of your brain will exhibit electrical activity when you read certain words and phrases.
Two types of "brain mapping"
Before we dive further into the field of brain mapping, let's first define what we're talking about. There are actually two types of brain mapping.
The first type, which is what we are concerned with, is described by the Society for Brain Mapping & Therapeutics as "the study of the anatomy and function of the brain and spinal cord through the use of imaging, immunohistochemistry, molecular and optogenetics, stem cell and cellular biology, engineering, neurophysiology, and nanotechnology." One might fairly add physics and quantum physics to that list.
Credit: santiago silver / Adobe Stock / Big Think
The second type of brain mapping deals with identifying areas of the brain using qEEG technology in order to strengthen or heal them through neurofeedback training. Neurofeedback practitioners claim some impressive therapeutic value for people with all sorts of conditions relating to the brain, including ADHD, autism, depression, and anxiety. Some experts have expressed skepticism about some such claims. The jury's still out on this type of brain mapping.
What kind of map could map the brain?
A brain map, therefore, could be something like an atlas — a collection of maps that document various neural pathways. But, unlike a road map, it can't be two-dimensional. A brain map of the cortex alone would have to be three-dimensional.
The number of interconnections, or synapses, across which neurons communicate via chemical and electrical signals is believed to be about 125 trillion.
The cortex, or gray matter, which contains billions of neurons and synapses is folded in such a way that sections that would be distant from each other come into close proximity. This is useful because it shortens the distance that signals have to cross from one part of the brain to another. The folds also greatly increase the cortex's surface area, which means we can cram more gray matter inside our skulls.
Folding itself is implicated in some neural disorders, and scientists wonder if we might one day be able to modify a brain's folding.
Credit: PhD Comics
A need for unprecedented collaboration
- Maps have always betrayed the bias of their creators. Even neural cartographers will inevitably develop maps that depict the brain according to their understanding of its workings. At the same time, it's exciting to imagine breakthroughs that could occur should a map unexpectedly not conform to its makers expectations.
- One size does not fit all. Scientists strongly suspect each brain is at least somewhat unique. To construct brain maps that encompass differences between us, researchers will have to engage in some generalizing that will inevitably reduce their accuracy as it enhances their universality.
- Financial considerations make the requisite collaboration between scientists and institutions difficult. The hardware and expertise required mean that brain mapping will be costly. However, for those who discover new medical treatments or technologies along the way, the endeavor could prove profitable. Thus, some will no doubt feel that they have financial incentives not to share information.
Ultimately, La Monica's third consideration touches upon what may be the human brain mapping's biggest underlying challenge. As UCLA Health notes, the project is the polar opposite of "reductionistic approaches in medical science." Instead, "brain mapping integrates many sources of information to produce a holistic view, the value of which is greater than the sum of its parts."
Credit: gerasimov174 / Adobe Stock
This will demand an unprecedented level of collaboration and cooperation between organizations and scientists from a broad swath of scientific disciplines.
Brain mapping for the win
There is almost nothing about mapping the human brain that will be easy. From logistical issues (like the open exchange of information) to scientific challenges (such as technological and theoretical advances), much will be required to make sense of the human brain.
With the brain so central to our being, there's a tremendous amount of research relating to it. There's a continual stream of new insights regarding the way it functions and the ways it sometimes doesn't function so well.
For scientists seeking to understand the brain, and for doctors working to help their patients enjoy life to its fullest, a comprehensive map that brings all of the best, most recent information together is more than worth the Herculean effort required to make it happen.
A new study says the reason cave paintings are in such remote caverns was the artists' search for transcendence.
- Hundreds of prehistoric paintings have been found in subterranean chambers with barely enough oxygen to breathe.
- Low oxygen causes hypoxia that can induce exalted mental states.
- A new study says the artists chose these hard-to-each caverns in search of an oxygen-starved high.
Artists of all types have been known to ingest a — shall we say — creative lubricant or two. One of the paradoxical things about art, even for people who love making it — maybe especially for those people — is that it's sometimes hard to get started, despite the fact that it's even harder to stop.
A new paper suggests this problem and solution go way back.
As archaeologist Yafit Kedar from Tel-Aviv University in Israel was in France enjoying some cave art deep within the ground, she started to wonder why their creators would choose to create images so far away from natural light sources. These places are also airless, where what little oxygen there could have been would have been consumed by the burning torches the painters needed in order to see what they were painting.
Maybe, she thought, the reason these long-ago artists chose to create in such remote chambers was because of their lack of fresh oxygen. Perhaps the painters would have been down there creating in a hypoxic, trancelike state. In that pre-agricultural, pre-chemistry time, cave painting might have been a way to get inspirationally baked.
There are some 400 known prehistoric cave paintings found in Western Europe dating back to the Upper Paleolithic period from 40,000 to 11,00 years ago.
The Greek oracles were probably high, too
Credit: matiasdelcarmine/Adobe Stock
This might not be the only historical example of people inducing an oxygen-starved state to achieve transcendence or something like it. A 2006 study from scientists at the National Institute of Geophysics and Volcanology in Rome hypothesized that hypoxia might have been the source of the trances out of which Delphic oracles extracted their visions.
Plutarch had written that trances began when the oracle—really generations of female oracles, all of them ceremonially named "Pythia" — inhaled sweet noxious fumes from cracks in the ground beneath the temple. Lead author of the 2006 study Giuseppe Etiope suggested that these gasses may well have been nothing more miraculous than carbon dioxide and methane filling a poorly ventilated space, thus casting Pythia off into a netherworld of semi-consciousness.
The air down there
Credit: Aleksandr Volunkov/Adobe Stock
On the surface, the air we breathe is 21 percent oxygen. Kedar and her colleagues created computer models that revealed the likely levels of oxygen in the painted caves. They found that in some such caverns, oxygen levels can drop to 18 percent in just 15 minutes. Some models fell to 11 percent. Hypoxia is likely at oxygen levels below 14.5% percent.
Fire torches exacerbate the problem. Up near the surface in a cave open to outside air, a burning fire's exhaust flows up and out while fresh air comes in beneath it. In a narrow passageway, however, the carbon dioxide and oxygen mix, and the lighter oxygen floats upward and on out of the cavern toward the surface.
The deeper a painter went with their torch, the more extreme was the loss of oxygen. Some of Kedar's models of deep caverns found just 9 percent oxygen, the lower limit of survivability.
Kedar hopes to validate the modeled outcomes by measuring oxygen levels in existing painted caves. For now though, the models point to the "transformative nature of an underground, oxygen-depleted space."
What is a hypoxic high like?
Hypoxia releases dopamine and can produce euphoria, visions, and out-of-body sensations. Modern visitors have reported experiencing some of these same sorts of mental phenomena when viewing the artwork.
The paper suggests that, "The cave environment was conceived as both a liminal space and an ontological arena, allowing early humans to maintain their connectedness with the cosmos." The hypoxic mind may well have found it easy to imagine that they were seeing beyond the rock, and indeed, beyond their world.
"The images envisioned in such a hallucinatory state appear to float on the cave surfaces (walls, floors, and ceilings) as if these constituted a membrane connecting the upper and lower worlds," write the authors.
Considering the likelihood of hypoxic conditions inside caves, it may be that it was the promise of a transcendent experience that drove the painters deep into the ground rather than any inherent meaning attached to the caves. As the paper concludes:
"It was not the decoration that rendered the caves significant; rather, the significance of the chosen caves was the reason for their decoration."
A powerful new tool lights up the brains of worms, and may soon help draw maps of other animals brains.
- A new tool called NeuroPal allows scientists to map the brain in more detail than ever before.
- By using the same color highlight for similar neurons, it allows researchers to more fully understand what areas of the brain do what.
- It has already been made available to other researchers who are publishing new brain studies.
The human brain is one of the most complicated things in the known universe. A fatty mass containing 86 billion neurons connected by 100 trillion synapses, it automatically regulates the foundational bodily functions, reviews sensory data to permit the business of living, and is capable of abstract thought of dazzling complexity and brilliance.
Exactly how these cells and connections do this remains a mystery, however. These endless connections are difficult to trace, and how different parts of the brain work together—and even what the various components do—is still the subject of cutting edge research.
That research will soon be a little bit easier and a lot more colorful due to a new technique by scientists at Columbia that can light up neurons and synapses in vibrant tones.
I’ve heard of a vibrant imagination, but this is ridiculous.
NeuroPAL (Neuronal Polychromatic Atlas of Landmarks) is a genetic engineering technique that lights up neurons in fluorescent, easily discerned colors. Neurons expressing the same genetic information will be the same color under a microscope, allowing scientists to produce an easily readable map showing which neurons have similar genetic details and functions. This provides much more information than previous methods. When combined with other techniques that record the communications between cells, it can provide previously impossible insights into neural network dynamics.
In this study, published in Cell, the scientists used NeuroPal on Caenorhabditis elegans (C. elegans) worms and on computer screens.
C. elegans is commonly used in biological science for experimentation. A tiny creature, they have a comparatively simple and well-mapped nervous system. Previous studies using electron microscopes have mapped the connections in the worm's brain but have faced difficulties identifying every neuron in the system. As mentioned, NeuroPal can identify every neuron that expresses certain genetic features.
Using this tool, the study found that the connections in this animal's brain are much more complicated than previously known.
The researchers also created a computer program that provides optimal color schemes for using NeuroPal in other, more complicated animals.
What use is a mapped brain, exactly?
By providing a way to reliably identify different types of neuron cells and visibly present them for observation, NeuroPal will make creating comprehensive brain maps much simpler. In the discussion section of the recent study, the authors explain the potential uses of this tool in expanding our understanding of neural networks, including those not belonging to small worms:
"To date, functional networks have been investigated by recording the activity of small subsets of labeled neurons. More recent work has inaugurated whole-brain activity imaging with cellular resolution. However, the inability to reliably identify all neurons within whole-brain recordings has precluded a full picture with circuit-level details […] Coupling NeuroPAL with whole-brain activity imaging methods permits a unified view of network dynamics, across animals, without sacrificing circuit-level details."
"Being able to identify neurons, or other types of cells, using color can help scientists visually understand the role of each part of a biological system. That means when something goes wrong with the system, it may help pinpoint where the breakdown occurred."
NeuroPal has already been given to other researchers, and published studies utilizing it are beginning to trickle out. It is only a matter of time before this tool provides us with a much-improved understanding of the brain and its functions.
A new study provides validation for the recently identified phenomenon.
- Aphantasia, a recently identified psychological phenomenon, describes when people can't conjure visualizations in their mind's eye.
- A new study published in Cortex compared the visual memories of aphantasic participants with a group of controls.
- Its results found experimental validation for the condition.
Escapism is one of the imagination's great joys. Through fantastic literature, we can explore the vast stretches Arrakis's deserts or the forests of Middle Earth alongside Gandalf the Grey. We can embark on vacations weeks in advance and enjoy a sunny beach while at our desks. We can relive a cherished memory with a favorite relative in an instant, and, of course, always rely on our flock of trusty sheep to lull us to sleep.
We manage this through what is colloquially called "the mind's eye," our ability to generate psychological images without sensory input. However, such escapism is not possible for people with the rare, and only recently identified, condition aphantasia. People with aphantasia cannot conjure mental images—original or from memory. Instead, their minds' eyes produce dark, blank canvases that cannot be painted in. As Wilma Bainbridge, an assistant professor of psychology at the University of Chicago, told UChicago News:
"Some individuals with aphantasia have reported that they don't understand what it means to 'count sheep' before going to bed. They thought it was merely an expression, and had never realized until adulthood that other people could actually visualize sheep without seeing them."
For such individuals, literature may produce facts but not visual representations. Arrakis isn't a planet of vast deserts but vast emptiness, Gandalf the Grey a colorless, featureless blob. Sunny beaches can't be visited in their imaginations but must remain on the office calendar until summer vacation. And while memories exist, they cannot be visually recalled except between scrapbook cellophane.
Scientists don't yet know what causes aphantasia, whether it's a distinct psychological condition, or, indeed, if we are simply jarring against language's limited ability to accurately describe our internal realities. But a burgeoning body of research—among it a new study led by Bainbridge and published in Cortex last month—suggests the condition is more than misfiring expressions.
Changing our understanding of the mind's eye
Francis Galton was the first to describe a condition that would today be recognized as aphantasia.
Though no long-term studies have focused on aphantasia, its history stretches back more than a century. Francis Galton first described people with "no power of visualising" in 1880, an observation made during his breakfast-table survey. At that time, however, the science of psychology was still in its infancy, and Galton's observation was shelved like so many other early-day curios—brought down and dusted off by the occasional psychologist but given little attention before being shelved again.
That changed in 2003 when neurologist Adam Zeman was contacted by a 65-year-old man who claimed his mind's eye went blind. During a coronary angioplasty, the man suffered a small stroke that damaged his brain. Afterward, he lost his ability to render psychological imagery.
"He had vivid imagery previously," Zeman told Science Focus. "He used to get himself to sleep by imagining friends and family. Following the cardiac procedure, he couldn't visualise anything, his dreams became avisual, [and] he said that reading was different because previously he used to enter a visual world and that no longer happened. We were intrigued."
Zeman and his colleagues began a case study into the man's condition. Tests found he could describe objects and their color but could not visualize them. (He claimed he simply knew the answer.) He could rotate three-dimensional images in his mind, but it took him longer to manage than controls. And brain imaging showed brain regions associated with visualization to be dark when he tried to imagine images.
Zeman published his case study, and it was subsequently featured in Discover magazine. After the story's publication, more people reached out to Zeman. They too claimed their minds' eyes were blind, but unlike Zeman's original subject, many of these people had lived with the condition their entire lives. They only became aware of their condition later in life when, as Bainbridge mentions above, they realized that the mental worlds described by friends and family were based on more than fanciful expressions.
While some managed to live normal, even thriving, lives without visual memory, others found the condition distressing. As one subject told Zeman and his coauthors: "After the passing of my mother, I was extremely distraught in that I could not reminisce on the memories we had together. I can remember factually the things we did together, but never an image. After seven years, I hardly remember her."
Zeman published another case study focusing on 21 of these individuals in 2015. It was here that he coined the phrase* "aphantasia," from the Greek phantasia meaning "imagination." Since then, Zemen has connected with thousands of people claiming to have the condition, and his studies have raised intriguing questions for researchers interested in memory and the mind.
Visualizing the difference
On the left, an aphantastic participant's recreation of a photo from memory. On the right, the participant's recreation when the photo was available for reference.
Bainbridge is one such researcher. Her previous work has focused on perception and memory, both their underlying mechanics and how this content is stored. In her latest study, she and her co-authors aimed to not only tease out the distinctions between object and spatial memory but also deepen our understanding of aphantasia.
To do this, they invited 61 people with aphantasia and a group of controls to participate in their experiment. They showed each participant a photo of a room and then asked them to draw it in as much detail as possible. For one test, the participants were allowed to keep the photo for reference. For the next test, however, they had to draw the room from memory. Bainbridge and her coauthors then put the drawings online to be quantified by nearly 3,000 online assessors, who were asked to score both sets of test images for object and spatial details.
The results showed the aphantastic participants had difficulty with the memory experiment. They produced reproductions with fewer objects, less color, and fewer details than their control peers. Many leaned on verbal scaffolding in lieu of visual details—for example, one participant drew a rudimentary box with the word "window" rather than a window with a frame and panes of glass.
Although the aphantastic patients drew rooms with fewer objects, they were very accurate in their placement of those objects. They also made fewer errors than the controls and avoided incorporating features and furniture absent in the original images. The researchers write that this suggests high spatial accuracy despite a lack of visualization.
"One possible explanation could be that because aphantasics have trouble with this task, they rely on other strategies like verbal-coding of the space," Bainbridge told UChicago News. "Their verbal representations and other compensatory strategies might actually make them better at avoiding false memories."
The online assessors found no significant differences between the aphantastic participants and the controls when the original photo was available for reference. In fact, some of the aphantastic participants produced stunningly accurate and artistic recreations during this test.
Bainbridge and her coauthors suggest that these results not only support the idea that object and spatial information is store in separate neural networks. They also provide "experimental validation" for aphantasia as a valid psychological phenomenon.
Discovering a new reality in aphantasia?
And Bainbridge's study has joined an ever-growing panoply. A 2018 study, also published in Cortex, measured the binocular rivalry—the visual phenomenon in which awareness fluctuates when different images are presented to each eye—of participants with and without aphantasia. When primed beforehand, control participants choose the primed stimuli more often than not. Meanwhile, aphantastic participants showed no such favoritism, whether primed or not. Like Bainbridge's study, these results suggest a physiological underpinning for aphantasia.
Another critical factor is growing awareness. As more studies and stories are published, more and more people are realizing they aren't alone. Such a realization can empower others to come forward and share their experiences, which in turn spurs researchers with new questions and experiences to study and hypothesize over.
Yet, there's still much work to be done. Because this psychological phenomenon has only recently been identified—Galton's observation notwithstanding—there has been sparingly little research on the condition and what research has been done has relied on participants who self-report as having aphantasia. While researchers have used the Vividness of Visual Imagery Quiz to test for aphantasia, there is currently no universal method for diagnosing the condition. And, of course, there is the ever-vexing question of how one can assess one mind's experiences from another.
"Skeptics could claim that aphantasia is itself a mere fantasy: describing our inner lives is difficult and undoubtedly liable to error," Zeman and his co-authors wrote in their 2015 case study. "We suspect, however, that aphantasia will prove to be a variant of neuropsychological functioning akin to synesthesia [a neurological condition in which one sense is experienced as another] and to congenital prosopagnosia [the inability to recognize faces or learn new ones]."
Time and further research will tell. But scientists need phenomenon to test and questions to experiment on. Thanks to researchers like Zeman and Bainbridge, alongside the many people who came forward to discuss their experiences, they now have both when it comes to aphantasia.
* Zeman also coined the term "hyperphantasia" to describe the condition in which people's psychological imagery is incredibly vivid and well-defined.
It's hard to stop looking back and forth between these faces and the busts they came from.
- A quarantine project gone wild produces the possibly realistic faces of ancient Roman rulers.
- A designer worked with a machine learning app to produce the images.
- It's impossible to know if they're accurate, but they sure look plausible.
Imaginative as humans are, it's often hard not to see historical figures depicted in black-and-white photos as being somehow of another species. Confronted with colorized images can be startling — hey, they look like us — bringing home at last what they were really like. Maybe that person evens look like someone we know.
The same is true of figures whose appearance we know only from their statues, maybe even moreso. We may know their names and something about them, but, again, it's all sort of not quite real. Now cinematographer and virtual reality designer Daniel Voshart has published amazing, life-like images of 54 Roman emperors based on their statues. He used machine learning and filled in the (many) remaining blanks with his imagination. While he's careful to point out that his renderings are merely what these individuals may have looked like, they're remarkably plausible, and also remarkably familiar.
Voshart describes the whole thing as a quarantine project that got out of hand, but lots of people are excited about what he's done, and are purchasing posters of his Roman emperors.
How the Roman emperors got faced
Credit: Daniel Voshart
Voshart's imaginings began with an AI/neural-net program called Artbreeder. The freemium online app intelligently generates new images from existing ones and can combine multiple images into…well, who knows. It's addictive — people have so far used it to generate nearly 72.7 million images, says the site — and it's easy to see how Voshart fell down the rabbit hole.
The Roman emperor project began with Voshart feeding Artbreeder images of 800 busts. Obviously, not all busts have weathered the centuries equally. Voshart told Live Science, "There is a rule of thumb in computer programming called 'garbage in garbage out,' and it applies to Artbreeder. A well-lit, well-sculpted bust with little damage and standard face features is going to be quite easy to get a result." Fortunately, there were multiple busts for some of the emperors, and different angles of busts captured in different photographs.
For the renderings Artbreeder produced, each face required some 15-16 hours of additional input from Voshart, who was left to deduce/guess such details as hair and skin coloring, though in many cases, an individual's features suggested likely pigmentations. Voshart was also aided by written descriptions of some of the rulers.
There's no way to know for sure how frequently Voshart's guesses hit their marks. It is obviously the case, though, that his interpretations look incredibly plausible when you compare one of his emperors to the sculpture(s) from which it was derived.
It's fascinating to feel like you're face-to-face with these ancient and sometimes notorious figures. Here are two examples, along with some of what we think we know about the men behind the faces.
One of numerous sculptures of Caligula, left
Caligula was the third Roman Emperor, ruling the city-state from AD 37 to 41. His name was actually Gaius Caesar Augustus Germanicus — Caligula is a nickname meaning "Little Boot."
One of the reputed great madmen of history, he was said to have made a horse his consul, had conversations with the moon, and to have ravaged his way through his kingdom, including his three sisters. Caligula is known for extreme cruelty, terrorizing his subjects, and accounts suggest he would deliberately distort his face to surprise and frighten people he wished to intimidate.
A 1928 journal, Studies in Philology, noted that contemporary descriptions of Caligula depicted him as having a "head misshapen, eyes and temples sunken," and "eyes staring and with a glare savage enough to torture." In some sculptures not shown above, his head is a bit acorn-shaped.
One of numerous sculptures of Nero, left
There's a good German word for the face of Nero, that guy famous for fiddling as Rome burned. It's "backpfeifengesicht." Properly named Nero Claudius Caesar Augustus Germanicus, he was Rome's fifth emperor. He ruled from AD 54 until his suicide in AD 68.
Another Germanicus-family gem, Nero's said to have murdered his own mother, Agrippa, as well as (maybe) his second wife. As for the fiddling, he was a lover of music and the arts, and there are stories of his charitability. And, oh yeah, he may have set the fire as an excuse to rebuild the city center, making it his own.
While it may not be the most historically sound means of assessing an historical personage, Voshart's imagining of Nero does suggest an over-indulged, entitled young man. Backpfeifengesicht.