Our sweets cravings may have set the stage for the human brain to become big and powerful. That’s the finding of a new study.

The brains of our upright-walking ancestors, some 4 million years ago, weighed only around 300 grams (11 ounces). That’s about equal to a medium apple. Today, the human brain averages 1,500 grams (3.3 pounds). That’s about equal to 1.5 liters of water. Much of this brain expansion took place before early humans mastered both fire and cooking. That’s a point that marked when they could start regularly dining on energy-dense starches.

Carbohydrates come in two main classes. Sugars tend to be relatively simple molecules. Starches tend to be bigger and more complex. A new analysis of existing data from human ancestors, as well as chimps, suggests that a large share of their energy probably came from sugary carbs, such as those in fruits and honey.

Simple sugars may have played an overlooked — but important — role in human evolution, researchers now conclude. They describe why in the August 6 Science.

Until now, much of how diet affected human evolution has centered on meat. Around 2.5 million years ago, our early upright-walking ancestors began eating more meat — raw at first, then eventually cooked. Meat is rich in protein and fat. And that appeared to play a big role in fueling our ancestors’ ever-expanding brains.

But Jennie Brand-Miller thought there might be more to the story. A nutrition scientist at the University of Sydney, in Australia, she wondered how sugars might have affected the evolution of our brains.

A 2017 study had shown that fruit-eating primates had bigger brains than leaf-eating ones. Eating fruit boosts demands on various thought processes, other researchers had suggested two decades earlier. Might this have kickstarted the evolution of big brains in humans?

Explains Brand-Miller, “You need to remember when various species of ripe fruit begin to ripen, then you need to remember where it is in the forest.” And, she adds, “Your memory is associated with a bigger brain.”

Fossil primates and later hominids, such as Homo erectus, showed signs of tooth decay, Brand-Miller notes. This suggests a diet containing soft, sugary foods. (Homo erectus was the first of our ancient cousins to venture outside Africa; that was 2 million years ago).

“All these things kept adding pieces to this lovely tapestry, this puzzle that said fruit-containing sugars must be important [in human evolution],” she says.

Still, what about meat?

Brand-Miller is part of a team that has now calculated the dietary needs of chimps, humans and three early species of human ancestors. To do this, the researchers combined data from fossils, teeth, the species’ metabolism and the biology of bodily processes.

Our earliest chimp-like ancestors from around 4 million years ago were largely vegetarians, they found. Fruit likely provided more than two-thirds of their food energy. And it played a big role as hominid brains grew over the next few million years, the data also suggest.

Clever foraging skills would have helped fuel their energy-sapping brains. These would have included hunting, cracking nuts, grinding seeds or extracting bone marrow. Later, once cooking became common, humans could have turned to starches (such as grains, beans and tubers). But a constant need for sugary foods appears to have been a key player in our evolution. And it didn’t disappear after a shift to foods high in proteins and fat, such as meats.

Meat and sugars? “I see them as parallel stories, not one replacing the other,” Brand-Miller now says. “Animal foods were clearly important. They’re very nutrient dense.”

A past focus on meat-eating may have missed some food trends that helped build the human brain, agrees Julie Lee-Thorp. She’s an archaeologist at the University of Oxford in England. She did not take part in the new study.

Focusing on meat’s role may reflect a modern bias, she adds. “Meat is a high-status food today,” notes Lee-Thorp. “And that has perhaps been carried over into the way we think about the past.”

But Brian Wood largely dismisses that. The study of human evolution has not been obsessed with meat-eating, he says. A biological anthropologist, Wood works at the University of California, Los Angeles. A diverse range of foods fueled our evolution, he says. And they were made possible by our growing “ability to capture and harvest high-quality, difficult-to-acquire foods.” This included hunting, sure. But, he adds, foraging for fruit, honey, nuts and the underground parts of plants was also part of it.

The transplanted cells formed circuits, reached the spinal cord and responded to injury.

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The animals may help reveal the causes of brain disease in people and point the way to treatments. But researchers already are calling for new ethical guidelines.

Experts say that after childbirth, intrusive thoughts are common and mostly benign. Lindsay Clancy’s story provides a disturbing exception.

Scientists have uncovered two surprising forces that help guide how the human brain forms before birth. Before birth, the human brain is shaped in large part by an unusual class of stem cells known as radial glia. These cells help determine which brain cells are produced, when they appear, and how the cerebral cortex, the [...]

Models of the insect’s nervous system have been trained to solve a Rubik’s Cube, play video games and even parallel park a car.

Models of the insect’s nervous system have been trained to solve a Rubik’s Cube, play video games and even parallel park a car.

The evolutionary part of this paper relies on wishful thinking. What “could” or “might” happen occurs only in their evolutionary imaginations.

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Alzheimer’s may begin to unravel the brain when a small group of neurons switches on a receptor it was never meant to use, triggering damage that spreads from synapses to memories. Alzheimer’s disease is often defined by amyloid plaques and tau tangles, but those hallmarks are part of a much wider breakdown. Neurons become overactive, [...]

Children with ADHD showed more erratic pupil responses, a pattern that shifted with medication.

The device made by Flow Neuroscience is approved by the FDA and could help people get off antidepressants—but it costs $2,200.

As far as completely pointless ways to kill time on your phone, this is certainly one of the weirdest on record.

Behold the all-new invention of so-called “dopamine sites” — digital domains where you can browse and hunt for deals on nonexistent wares and services. Clothes, food delivery, you name it: you can pretend-shop for it all. 

You don’t actually buy anything, crucially. You’re just pretending to have money to buy the things you want. It’s window-shopping reimagined for the age of doomscrolling.

But it’s also a little more than that. These cleverly-built sites simulate the experience down to checking out and “tracking” your shipment or delivery, and their absurdly realistic rituals can help people become more conscious of their spending habits. Supposedly. 

The trend, according to the New York Times, originated in South Korea this spring, when Park Seohyun, a 21-year-old mechanical engineering student in Seoul, created a fake food-delivery site called “Food Never Arrives.” (It’s now an app).

Originally intended as a joke, she says, it lets you not only order nonexistent food, but provides you an estimate of the money and calories you saved by skipping on the real thing. 

In a wintry economic climate, it became an unexpected hit.

“People began sharing it online and discussing whether it actually helped them resist ordering food,” Park told the NYT.

A wave of imitators followed. This summer marked the launch of “FakeHaul,” a dopamine site built by a Microsoft engineer that convincingly imitates shopping on Temu. Two developers in India inspired by Park’s site, Purvansh Parmar and Anshul Sharma, created “Food Never Comes,” which simulates food deliveries but provides real recipes for the food you didn’t actually order. Parmar and Sharma told the newspaper that their site had more than 2.7 million views since launching in June.

Whether these dopamine sites provide anything more than fleeting, empty pleasures is something experts are more skeptical about. Ravi Dhar, director of the Yale Center for Customer Insights, told the NYT that the “element of looking forward brings a lot of the pleasure, and we often crash after an event or feel let down.” Lingguo Xu, a behavioral economist studying anticipatory utility, warned that the dopamine tricks could quickly get old. And by simulating consumption, you risk developing “stronger cravings.”

Some take the original idea beyond getting high on simulated shopping. Ko Seojin, another South Korean developer, created a website for taking virtual smoke breaks called Damta World. You click to start smoking an animated cigarette, which starts burning on screen. You can “whisper” disappearing messages to other smokers on break, while a counter keeps track of the number of cigarette butts that have been tossed on the office rooftop each day.

Ko told the NYT that 150,000 people visit each month, and she says that some users have become real-life friends after meeting on the website. Those friendships, we hope, are something that’ll last longer than any fake-shopping dopamine hit.

More on your brain on tech: Psychologist Says AI Is Causing Never-Before-Seen Types of Mental Disorder

The post Bizarre New Websites Are Designed Specifically to Spark Dopamine in Your Brain appeared first on Futurism.

The US government has been sharing more information about UFOs. That's fueling excitement over the possibility of the president announcing that humans are not alone.

The US government has been sharing more information about UFOs. That's fueling excitement over the possibility of the president announcing that humans are not alone.

It’s easy to see why people might latch onto the idea of a reptilian brain as an explainer, or an explainaway, for complex topics.

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For the 25th anniversary of 9/11 you may be wondering what to read or watch for the occasion. I have a few suggestions.

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After nearly two decades of work, scientists have completed a wiring diagram of the central nervous system of an adult male fruit fly (Drosophila melanogaster).

The post Researchers Unveil Complete Fruit Fly Connectome appeared first on Sci.News: Breaking Science News.

Depression in later life may be an early warning from the brain, appearing years before Alzheimer’s begins to affect memory and thinking A new study in JNeurosci found that faster accumulation of tau, a protein closely tied to Alzheimer’s, was associated with worsening depressive symptoms in older adults who remained cognitively healthy. Teodora Markova of [...]

On Friday, researchers announced the completion of a map of every neuron in the brain of a male fruit fly. The "connectome" provides a tool that can accelerate neurobiology research. But it also provides an opportunity to do some science on its own, as the connectome of a female Drosophila had been completed earlier this year. The work also provided the team behind it the opportunity to refine tools that are likely to be applied to ever-more complex nervous systems, including (potentially) those of vertebrates.

The new work involved a collaboration between biologists at the Howard Hughes Medical Institute's Janelia Research Campus and computer scientists at Google—both acknowledge that neither could have done the project without the other. Preparation of an entire brain for imaging at the necessary resolution requires a distinct set of skills, as does interpreting what those images indicate. But building a complete picture of the hundreds of millions of synapses in a brain as small as the fruit fly's is a task that can't be achieved by humans in a manageable amount of time.

The people behind the effort expect that in the long term, the effort will be worth it, as the connectome could give neurobiologists a valuable tool for understanding how the brain works.

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© Philip Hubbard/HHMI Janelia

A University of St. Andrews-led research team has proposed that the red wavelengths of flickering light emitted by early human ancestors’ campfires helped reprogram the human brain to boost social and verbal communication, leading to modern language and storytelling behaviors found only in humans.

The team, which included researchers from Dartmouth College, said the study builds on earlier theories linking fire and language to the extra hours it added to the day.

However, their findings suggest that the biological changes caused by fire use may have enabled complex language as much as fire-associated behavioral changes, accelerating the evolution of verbal communication away from the ape-like systems still used by modern apes toward more complex, “uniquely human” interactions.

Researchers Wondered if Firelight Reprogrammed the Human Brain

Catherine Hobaiter, a Professor of the School of Psychology and Neuroscience at the University of St Andrews and the lead author of a paper detailing the team’s idea, said she has always been fascinated by the origins of language.

“What was the first word?” the professor asked. “The first story?”

Unfortunately, Professor Hobaiter noted, many questions about the origin of humanity’s complex and diverse forms of verbal communication remain unanswered.

Some earlier research has explored a possible link between the first spoken words and the advent of controlled fire use. However, the team notes that most studies have focused primarily on the extra hours of practical light added to the end of each day.

Curious whether other biological mechanisms also contributed to the evolution of language and complex storytelling behavior, Professor Hobaiter and colleagues examined the effects of sitting around a campfire to see whether the emitted light could reprogram the human brain.

Potential Effects of Red Wavelengths and Flickering Lights

First, the team noted that one potential catalyst emitted by firelight that could help reprogram the human brain for complex language is the color of the light wavelengths emitted by campfires. Specifically, Hobaiter and colleagues noted that campfire light emits almost no blue wavelengths but instead mostly in the visible red spectrum.

Many modern studies have focused on the potentially adverse effects of exposure to blue light wavelengths from modern technology on sleep patterns and overall health. Conversely, the paper’s authors described the red wavelengths emitted from fire as ‘uniquely suited’ for human socializing, “allowing an extension to the day without negatively impacting sleep.”

Another component of firelight the study authors suggest could have reprogrammed the human brain for speech is the way a campfire behaves. Unlike a modern, steady light source, the authors noted that firelight “flickers.”

Hobaiter and colleagues said that neurons in the human brain synchronize firing patterns with external flickering lights. For example, flickering lights in movies and TV shows often come with warnings against possible neurological effects on vulnerable viewers. The research team said this mechanism might also help synchronize the behavior of those seated around the campfire, resulting in a much deeper feeling of connection.

Finally, the researchers noted that firelight emits infrared wavelengths, which may have also contributed to helping firelight reprogram the human brain for complex verbal communication.

Are We the Storytelling Ape?

When discussing the potential impact of their proposal, study co-author Nathaniel Dominy, the Charles Hansen Professor of Anthropology at Dartmouth College, said many of the chemical properties have been well researched. However, Professor Dominy also notes that understanding the properties of light that capture our attention and focus, thereby instilling “harmony and cooperation,” has received far less attention.

“Measuring these features is an exciting part of this project,” the study author added.

Professor Hobaiter agreed, while also noting the conundrum scientists face when explaining why humans speak, when “decades of research with other species has shown us that you don’t need language to learn from each other, to organize where and when to forage, to learn cultural knowledge about tools and songs, to co-ordinate hunting, or navigate social politics.”

“While other species share all these skills, there is a fundamental puzzle: we struggle to find evidence of key differences between human and ape communication,” Professor Hobaiter explained. “And yet, we are surrounded by evidence of human distinctiveness. For all their incredible, rich communication and cultures, no other ape is inventing algebra, writing King Lear, or heading out into interstellar space.”

“So, it’s especially exciting to be able to generate testable predictions, to be able to ask if, at the end of the day, we are the storytelling ape,” the professor added.

The paper “Firelight and the Origins of Spoken Language” was published in Proceedings of the Royal Society. 

Christopher Plain has spent the last six years as Associate News Editor and Head Science Reporter at The Debrief. Follow and connect with him on X, learn about his novels at plainfiction.com, or email him at christopher@thedebrief.org.