https://www.sciencealert.com/insulin-isnt-just-made-by-the-pancreas-heres-another-locat...

"Your brain makes insulin – the same insulin produced by your pancreas. The same insulin that is not produced in people with type 1 diabetes and the same insulin that does not work properly in people with type 2 diabetes.

***

"Insulin can and does move from the blood to the brain. But local sources of insulin are produced in specific places to do specific things.

***

"First, what is surprising about brain insulin production is that there is not one but at least six types of insulin-producing brain cell. Some have been confirmed in both rodent and human brain, others currently just in rodents.

"One of the first brain cells shown to make insulin is the neurogliaform cell. These live in a brain area important for learning and memory. Most surprisingly, the production of insulin here depends on the amount of glucose present – a feature shared with pancreatic beta cells.

"Its not clear what this insulin source does. Based on the location, it may contribute to cognitive function.

***

"...one insulin producing brain cell might regulate growth. A 2020 study showed that insulin is made and released from stress-sensing neurons in the mouse hypothalamus. This is a brain area that controls growth and metabolism. It also has the highest insulin levels in the human brain.

***

"Hypothalamic insulin maintained growth hormone levels in the pituitary gland. This is sometimes called the master gland as its involved in making or controlling production of other hormones. Having less local insulin meant less growth hormone production.

"Then there is the choroid plexus. This is the brain region that makes cerebrospinal fluid. In humans, that is about half a litre of this clear colourless liquid every day.

"Cells lining the choroid plexus – the epithelial cells – make a nourishing broth of growth factors and nutrients to keep the brain healthy. Only recently was insulin production found here in mice.

"The choroid plexus secretes fluid directly into brain ventricles, the spaces deep inside the brain. This fluid flows around the whole brain, perhaps delivering insulin more widely.

"One place it does travel to is the appetite control centre in the hypothalamus.

A 2023 study in mice showed that genetic control of insulin production by the choroid plexus could change food intake. The hypothalamus was rewired by changing choroid plexus insulin levels. Insulin released from here suppressed appetite.***

"There is still much to learn about brain insulin production. For example, which insulin source came first? The brain or the beta cell? Hopefully it doesn't take another 30 years to find out.

"But given the strength of evidence of brain insulin production, it won't be long until our school textbooks are updated."

Comment: since glucose is brain fuel it is logical that insulin is produced there to metabolize the glucose. It produces a fail-safe mechanism. The concept supports the design argument.

https://www.livescience.com/human-behavior/strikingly-simple-dial-in-the-brain-may-help...

"Imagination relies on an ability to differentiate between what's real and what's not — and now, scientists have uncovered potential brain mechanisms that make this distinction possible. These, they hypothesize, may be significant in conditions like schizophrenia, which can affect people's perception of reality.

"A paper published June 5 in the journal Neuron explored these mechanisms. Scientists know from previous research that a specific brain region — the fusiform gyrus, a large ridge that runs across two lobes of the brain — is active both when you see something in reality and when you imagine something, first study author Nadine Dijkstra, a neuroscientist at University College London, told Live Science.

"'But what we found was that the activity levels in that region predicted whether or not you think something is real, irrespective of whether you see or imagine it," she explained.

"The fusiform gyrus is involved in high-level visual processing, such as identifying objects and people's faces from their appearance. The study suggests that during imagination, the signal strength is weaker compared with during perception; this difference in signal strength enables the brain to distinguish between the two. That is, if the activity crosses a certain threshold, the brain interprets it as reality.

***

"The fMRI scans helped the researchers monitor the patterns of activity in specific parts of the brain associated with perception and imagination. The fusiform gyrus was active both when the lines were imaginary and when they were real. However, when the activity crossed a certain threshold, the study participants assumed it was real, Dijkstra said.

"'In general, the activation during imagination [alone] is not strong enough to cross this threshold," she added.

"When the activity in the fusiform gyrus went up, so did the activity of the anterior insula, a region in the brain's prefrontal cortex, which is broadly responsible for cognitive behaviors like decision-making and problem-solving. It's almost as if the anterior insula "reads out" a reality signal from the fusiform gyrus, the researchers noted in their paper. However, the mechanism behind this connection between the two brain areas is still unclear.

***

"The study suggests "our sense of reality is a judgment call based on signal strength, and by its very design, this system can be influenced by the power of our own mind," he told Live Science in an email. It's a "finding that helps explain how reality monitoring can fail, and lays the foundation for understanding complex experiences like hallucinations.'"

Comment: this is an early step in this aspect of brain research. Our brain must have a control of this sort, since we have such enormous intellectual capacity for imagination. I think lower forms of brains do not have this and it is a de novo development.

https://medicalxpress.com/news/2025-06-elav-protein-brain-unique-circular.html

"Deep within our nerve cells, a molecule is at work that has no beginning and no end. Instead of a straight chain, as is common for most RNA strands, it forms a closed loop. Known as circular RNAs (circRNAs), these molecules are crucial for development, thought, and synaptic function, yet their high prevalence in neurons has long been a scientific mystery. How does the brain produce so many of them?

"Now, Max Planck researchers from Freiburg have discovered a crucial mechanism that explains the remarkable abundance of circRNAs in the nervous system. Published in Genes & Development, the study reveals that the protein ELAV acts as a global master switch for the production of these molecules.

***

"The ring structure of circRNAs is crucial for their roles because it gives the molecules extreme stability. Unlike linear RNA molecules, circRNAs have no open ends that act as starting points for enzymes, which could rapidly degrade them. This longevity makes circRNAs ideal candidates for long-lasting regulatory tasks, especially in cells that don't divide, such as neurons.

"'They can control gene activity, act as sponges for other molecules, or even produce proteins. In our lab, we are fascinated by these RNAs and want to understand how they are regulated," says Mengjin Shi, one of the first-authors of the study.

"New research by the lab of Valérie Hilgers conducted on Drosophila embryos, identified the well-known RNA-binding protein ELAV as the key factor. The team found that in developing neurons, ELAV is the central mediator driving the widespread creation of circRNAs.

***

"'When we removed the ELAV protein from the fruit fly embryos, the production of neuronal circRNAs plummeted, with a downregulation by over 75%. Conversely, when we introduced ELAV into cells that normally produce very few circRNAs, it triggered their formation. This confirms ELAV's role as a potent regulator of circRNA expression," says Hilgers.

"The study also provides a clear mechanical insight into how ELAV performs this function: ELAV binds to pre-mRNA, the precursor to mature RNA. By binding there, ELAV slows down the standard process of "linear splicing," which in turn promotes an alternative process called "back-splicing." This action effectively brings the two ends of the future circRNA molecule together, facilitating the creation of the closed loop.

"'Our discovery suggests that neuronal circRNAs are not just byproducts of gene expression, but are purposefully generated to fulfill important functions. It enhances our understanding of the molecular basis of how the brain works by revealing how a specific type of molecule in neurons, circRNAs, is regulated. And ELAV is clearly a central part of that story," says Hilgers.

"Given that proteins similar to ELAV are conserved from flies to humans, these findings strongly suggest a similar mechanism governs circRNA production also in the human brain. By manipulating ELAV or similar proteins, the researchers could potentially influence circRNA levels providing new strategies to investigate the molecules' role in brain health and neurodegenerative disorders.

Comment: the genetic role in the nervous system becomes more complex. Tight controls are very important since neurons dont' divide and should not be altered in functions.

https://www.livescience.com/health/neuroscience/star-shaped-brain-cells-may-underpin-th...

"For decades, scientists believed neurons were the brain's sole architects of thought and memory — but now, new research suggests that another, often-overlooked type of brain cell may play a more central role in memory than previously thought.

"The study, published in May in the journal PNAS, proposes that these other brain cells, called astrocytes, could be responsible for the brain's impressive memory-storage capacity through a newly discovered kind of network architecture.

"Astrocytes are star-shaped cells that perform many maintenance tasks in the brain, including clearing cellular debris, supplying neurons with nutrients and regulating blood flow. They also sport thin branching structures, known as processes, that wrap around the points where neurons exchange messages. This wrapping forms what is called a tripartite synapse, a kind of three-way handshake involving the two connected neurons and the astrocyte.

***

"Astrocytes don't transmit electrical impulses like neurons do. Instead, they communicate via calcium signaling, sending waves of charged calcium particles within and between cells. Studies have shown that astrocytes respond to synaptic activity by altering their internal calcium levels. These changes can then trigger the release of chemical messengers from the astrocyte into the synapse.

"'These processes act as tiny calcium computers, sensing when information is sent through the synapse, passing that information to other processes, and then receiving feedback in return," Kozachkov said. Ultimately, this chain email gets back to the neurons, which adjust their activity in turn. However, researchers don't yet fully understand the precise computational functions astrocytes perform with the information they receive from neurons."

Comment: our consciousness must require this degree of complexity. I would say it is quite a design.

https://www.sciencealert.com/your-brain-wrinkles-are-way-more-important-than-we-ever-re...

"The folds and ridges of the human brain are more complex than any other in the animal kingdom, and a new study shows that this complexity may be linked to the brain's level of connectivity and our reasoning abilities. (my bold)

"Research led by a team from the University of California, Berkeley (UC Berkeley) looked at the brain shapes and neural activity of 43 young people, and in particular the lateral prefrontal cortex (LPFC) and lateral parietal cortex (LPC) – parts of the brain that handle reasoning and high-level cognition.

"The grooves and folds on the brain are known as sulci, with the smallest grooves known as tertiary sulci. These are the last to form as the brain grows, and the research team wanted to see how these grooves related to cognition.

"'The hypothesis is that the formation of sulci leads to shortened distances between connected brain regions, which could lead to increased neural efficiency, and then, in turn, individual differences in improved cognition with translational applications," says neuroscientist Kevin Weiner, from UC Berkeley.

"The analysis revealed each sulci had its own distinct connectivity pattern, and that the physical structure of some of these grooves was linked to the level of communication between brain areas – and not just areas that were close to each other.

"It adds to the findings of a 2021 study carried out by some of the same researchers, which found the depth of certain sulci are associated with cognitive reasoning. Now we have more data to help scientists understand why that might be.

"Between 60 and 70 percent of the brain's cortex (or outer layer) is hidden away inside folds, and these patterns change with age too. Tertiary sulci can vary significantly between individuals as well.

""While sulci can change over development, getting deeper or shallower and developing thinner or thicker gray matter – probably in ways that depend on experience – our particular configuration of sulci is a stable individual difference: their size, shape, location and even, for a few sulci, whether they're present or absent," says neuroscientist Silvia Bunge, from UC Berkeley.

"It's clear from this research that the peaks and valleys of these brain structures are much more important than previously realized. They're not just random folds used to pack brains inside skulls – and may have evolved in certain directions over time."

Comment: The 3-D relationships of cortical parts of the brain help create our cognitive abilities and must be considered part of the brain's plasticity ability.

https://www.sciencedaily.com/releases/2025/06/250603172903.htm

"A new study from Pitt researchers challenges a decades-old assumption in neuroscience by showing that the brain uses distinct transmission sites -- not a shared site -- to achieve different types of plasticity. The findings offer a deeper understanding of how the brain balances stability with flexibility, a process essential for learning, memory and mental health.

***

"...the researchers applied a chemical that activates otherwise silent receptors on the postsynaptic side. This caused spontaneous activity to increase, while evoked signals remained unchanged -- strong evidence that the two types of transmission operate through functionally distinct synaptic sites.

"This division likely enables the brain to maintain consistent background activity through spontaneous signaling while refining behaviorally relevant pathways through evoked activity. This dual system supports both homeostasis and Hebbian plasticity, the experience-dependent process that strengthens neural connections during learning.

"'Our findings reveal a key organizational strategy in the brain," said Yang. "By separating these two signaling modes, the brain can remain stable while still being flexible enough to adapt and learn.'"

Comment: A different form of plasticity than having new learned materials enlarge an area. It allows the brain an extreme form of plasticity while maintaining an equilibrium for the entire brain.

https://www.quantamagazine.org/how-much-energy-does-it-take-to-think-20250604/

"It often feels as though we allocate our mental energy through strenuous attention and focus. But the new research builds on a growing understanding that the majority of the brain’s function goes to maintenance. While many neuroscientists have historically focused on active, outward cognition, such as attention, problem-solving, working memory and decision-making, it’s becoming clear that beneath the surface, our background processing is a hidden hive of activity. Our brains regulate our bodies’ key physiological systems, allocating resources where they’re needed as we consciously and subconsciously react to the demands of our ever-changing environments.

***

"The human brain is incredibly expensive to run. At roughly 2% of body weight, the organ gorges on 20% of our body’s energetic resources. “It’s hugely metabolically demanding,” Jamadar said. For infants, that number is closer to 50%.

***

"The brain’s energy comes in the form of the molecule adenosine triphosphate (ATP), which cells make from glucose and oxygen. A tremendous expanse of thin capillaries — an estimated 400 miles of vascular wiring — weaves through brain tissue to carry glucose- and oxygen-rich blood to neurons and other brain cells. Once synthesized within cells, ATP powers communication between neurons, which enact the brain’s functions. Neurons carry electrical signals to their synapses, which allow the cells to exchange molecular messages; the strength of a signal determines whether they will release molecules (or “fire”). If they do, that molecular signal determines whether the next neuron will pass on the message, and so on. Maintaining what are known as membrane potentials — stable voltages across a neuron’s membrane that ensure that the cell is primed to fire when called upon — is known to account for at least half of the brain’s total energy budget.

***

"When performed simultaneously, PET and fMRI can provide complementary information on how glucose is being consumed by the brain, Jamadar said. It’s not a complete measure of the brain’s energy use because neural tissues can also convert some amino acids(opens a new tab) into ATP, but the vast majority of the brain’s ATP is produced by glucose metabolism.

"Jamadar’s analysis showed that a brain performing active tasks consumes just 5% more energy compared to a resting brain. When we are engaged in an effortful, goal-directed task, such as studying a bus schedule in a new city, neuronal firing rates increase in the relevant brain regions or networks — in that example, visual and language processing regions. This accounts for that extra 5%; the remaining 95% goes to the brain’s base metabolic load.

"Researchers don’t know precisely how that load is allocated, but over the past few decades, they have clarified what the brain is doing in the background. “Around the mid-’90s we started to realize as a discipline [that] actually there is a whole heap of stuff happening when someone is lying there at rest and they’re not explicitly engaged in a task,” she said. “We used to think about ongoing resting activity that is not related to the task at hand as noise, but now we know that there is a lot of signal in that noise.”

"Much of that signal is from the default mode network, which operates while we’re resting or otherwise not engaged in apparent activity. This network is involved in the mental experience of drifting between past, present and future scenarios — what you might make for dinner, a memory from last week, some pain in your hip. Additionally, beneath the iceberg of awareness, our brains are keeping track of the mosaic of physical variables — body temperature, blood glucose level, heart rate, respiration, and so on — that must remain stable, in a state known as homeostasis, to keep us alive. If any of them stray too far, things can get bad pretty quickly.

***

"A 5% increased energy demand during active thought may not sound like much, but in the context of the entire body and the energy-hungry brain, it can add up. And when you consider the strict energetic constraints our ancestors had to deal with, weariness at the end of a taxing day suddenly makes a lot more sense.

***

"To better understand these energetic constraints, in 2023 Padamsey summarized research on certain peculiarities of electrical signaling that indicate an evolutionary tendency toward energy efficiency. For one thing, you might imagine that the faster you transmit information, the better. But the brain’s optimal transmission rate is far lower than might be expected.

"Theoretically, the top speed for a neuron to feasibly fire and send information to its neighbor is 500 hertz. However, if neurons actually fired at 500 hertz, the system would become completely overwhelmed. The optimal information rate(opens a new tab) — the fastest rate at which neurons can still distinguish messages from their neighbors — is half that, or 250 hertz."

Comment: an overall constraint on burn rate is logical. The energy use is well known.

https://www.nature.com/articles/d41586-025-01655-2

"Special-agent immune cells carry information about the gut and fat tissue deep into the brain. This surveillance system, uncovered in mice, is crucial to the brain’s control of behaviour such as pursuit of food, researchers report today in Nature1.

"Similar immune cells are known to populate the membranes covering the brain, but the newly identified cells have molecular traits that give them entry into the core of the organ. Their function is shaped by diet and the microbiome; without them, even hungry mice are slow to eat.

***

"To gain a more definitive answer, Yoshida and her colleagues spent five years searching for T cells across the entire mouse brain. They found that T cells are concentrated in a hotspot in the subfornical organ, a structure in the centre of the brain that regulates a range of bodily processes, including eating and drinking. The scientists then sampled tissue from the human subfornical organ, where they also found T cells.

"In both mouse and human brains, the subfornical T cells were distinct from those found in the meninges. They produced more proteins that enabled them to reside in brain tissue and secreted more immune-signalling proteins known as cytokines under normal conditions.

"Curiously, the researchers found that the T cells from inside mouse brains were very similar to those in the animals’ fat deposits. To understand this similarity, they gave some mice a high-fat diet. These mice ended up with more T cells in their fat and brain tissues than did mice that ate standard food — evidence of a link between fat mass and brain T-cell populations. After mice on the same diet fasted for 48 hours, the number of T cells in their brains rose and the number in their fat fell, suggesting that food intake affects the number of T cells travelling to the brain.

"Next, the researchers used antibiotics to deplete populations of gut microorganisms in some mice. These animals’ levels of brain T cells decreased, which could mean that the microbiome influences immune-cell populations.

"Finally, the researchers assessed the potential role of the brain-resident T cells. Hungry mice that had been genetically engineered to lack the T cells took longer to find and consume food than did controls, suggesting that brain T cells play a part in feeding behaviour.

"More work is needed to uncover the mechanisms that enable brain T cells to influence eating and other functions, says Emanuela Pasciuto, a neuroimmunologist at the Vlaams Institute of Biotechnology in Antwerp, Belgium. This would require developing a whole new suite of tools that capture more than correlations, she adds. “That would be my wish experiment.'”

Comment: dhw will tell us how in tell us how intelligent the T cells are. This is a complex mechanism to control satiety, a very important function to halt overeating. It needs a designer not natural evolution,

https://www.sciencenews.org/article/silent-cells-surprising-brains

"These findings — from the brains of fruit flies, zebrafish and mice — open new possibilities for therapies aimed at mental illnesses such as depression and schizophrenia. They could also lead to a deeper understanding of how current therapies work.

"Astrocytes used to be thought of as helpers, assisting with grunt work in the brain. These starburst-shaped cells clean up waste between nerve cells, serve as barriers that keeps harmful threats out of the brain and guide nerve cells into forming connections with each other.

***

"Astrocytes grow until they meet another astrocyte, and form thousands of connections with other cells, “which means that every square millimeter of the brain is within the domain of an astrocyte,” Guttenplan says.

"Recent discoveries have revealed that the roles of astrocytes include a more sophisticated job: influencing messages at synapses, the connections between two nerve cells or neurons, and influencing behaviors. But how astrocytes were contributing to these neural conversations wasn’t clear.

***

"The new results, along with a growing body of research, suggest that astrocytes sense key chemical messages that were commonly thought to be intended for neurons and, in response, change the activity of neurons around them. Astrocytes seem to act as necessary intermediaries that sense key messages and relay them to nerve cells as needed.

"In the spinal cord equivalent of a fruit fly, for instance, a chemical signal called tyramine dramatically changes astrocytes. Tyramine is a “pay attention” signal, enabling astrocytes to respond to other chemical messages, including dopamine, the researchers found. Without the tyramine signal, astrocytes don’t respond to dopamine and other messages.

"The existence of this switch was “stunning,” says study coauthor Marc Freeman, also of Oregon Health and Science University. “The fact that an arousal cue could take an astrocyte from ignoring all of those major neurotransmitters to suddenly listening to everything … it boggles the mind when you think about the implications.”

***

“'There’s specificity to [astrocytes] being able to turn on and off the different knobs,” Guttenplan says. “It has effects on [neural] circuits as well as on whole animal behavior.”

"Similar findings came from a study on larval zebrafish, which found that astrocytes could change brain cell activity and control the animals’ behavior. And even more evidence comes from mouse brain cells, where astrocytes sensed norepinephrine, the mammalian counterpart of tyramine, and then altered nerve cell behavior.

***

"Understanding why brains evolved to include this layer of astrocyte oversight is a big question, Eroglu says. “There is something really beautiful here that remains to be understood.” She points to a warning issued from her former advisor, the late Ben Barres, a glial cell pioneer at Stanford University: Ignoring the astrocyte is always a mistake. b]"
(my bold)

Comment: The final point of the article tells us do not ignore any facet of an organism. From a design standpoint everyting we see is there for a reason.

https://medicalxpress.com/news/2025-05-groovy-brains-efficient.html

"Many grooves and dimples on the surface of the brain are unique to humans, but they're often dismissed as an uninteresting consequence of packing an unusually large brain into a too-small skull.

"But neuroscientists are finding that these folds are not mere artifacts, like the puffy folds you get when forcing a sleeping bag into a stuff sack. The depths of some of the smallest of these grooves seem to be linked to increased interconnectedness in the brain and better reasoning ability.

"In a study published in The Journal of Neuroscience, University of California, Berkeley researchers show that in children and adolescents, the depths of some small grooves are correlated with increased connectivity between regions of the brain—the lateral prefrontal cortex and lateral parietal cortex—involved in reasoning and other high-level cognitive functions.

"The grooves may actually bring those areas closer together in space, shortening the connections between them and speeding communications.

"The implication, the researchers say, is that variability in these small grooves, which are called tertiary sulci, may help explain individual differences in cognitive performance, and could serve as diagnostic indicators or biomarkers of reasoning ability or neurodevelopmental disorders.

***

"'We had explicit predictions about which tertiary sulci in the lateral prefrontal cortex would be functionally connected to tertiary sulci in the lateral parietal cortex, and that panned out," added Kevin Weiner, UC Berkeley associate professor of psychology and of neuroscience and a member of HWNI. "Prefrontal and parietal cortices aside, the hypothesis is that the formation of sulci leads to shortened distances between connected brain regions, which could lead to increased neural efficiency, and then, in turn, individual differences in improved cognition with translational applications."

***

"The brains of most animals, mammals included, have smooth surfaces. Primates have hills and valleys covering their cerebral cortex. While one group of primates, the New World monkeys called marmosets, have shallow, barely perceptible sulci, those of humans are deeply incised, with between 60% and 70% of the cortex buried in these folds.

"The cortical folding patterns in humans also change with age, establishing their final structure late in prenatal development while becoming less prominent in old age.

***

"The smallest grooves, many of which are uniquely human, are called tertiary sulci because they appear last in prenatal development and are never as deep as the major or primary sulci that are most evident on the cerebral surface.

***

"Across these individuals, greater depth for several of the sulci implicated in reasoning was associated with higher network centrality across the set of prefrontal and parietal sulci.

***

"Do we think that an individual's capacity for reasoning is set in stone based on their cortical folding? No," she said. "Cognitive function depends on variability in a variety of anatomical and functional features, and importantly, we know that experience, like quality of schooling, plays a powerful role in shaping an individual's cognitive trajectory, and that it is malleable, even in adulthood."

***

"'Dozens of brain maps have been proposed in just the last five years, but they disagree about the areas of associated regions in the cortex, and there are mismatches between areas at the group and individual level," Weiner said. "Examining network architecture based on individual sulcal morphology circumvents these disagreements and mismatches, with the opportunity to glean network-level insight from the local sulcal anatomy that is specific to a given individual.'"

Comment: That it is hard to map the brain with such individual variability to cover, is explained by the brain plasticity accommodating itself to the needs of each individual. Packing a brain into a small skull producing groves is empty thinking. Start with the premise based on design theory, everything is there for a reason.

https://mail.google.com/mail/u/0/#trash/FMfcgzQbfLWxPPwbTWKtfhGGxSvpHVKn

They discovered that, when calcium builds up in astrocytes, they release the energy-carrying "molecule ATP into the space between cells. Enzymes convert the ATP into adenosine, a known neuromodulator in the brain, which then activates neurons in the hindbrain and causes the fish to stop swimming.

“'It was surprising to me because it seems like such an indirect pathway,” lead study author Alex Chen says in a statement. “First of all, a non-neuronal cell is involved and then, second of all, there’s this biochemical circuit instead of some sort of neuronal circuit that implements this behavior.” This type of indirect circuit operates on a much slower time scale than neural circuits and could be useful for changes in behavior that occur over periods of seconds or minutes, the team speculates.

***

"the new study describes experiments in mice that demonstrated that norepinephrine actually triggers a wave of coordinated activity in astrocytes, which use their calcium levels to regulate how the neuromodulator affects synapse activity. “ It seems that a lot of brain wiring and activity is probably orchestrated by astrocytes, on slower timescales,” senior study author Thomas Papouin explains in a statement. “This is the type of discovery that profoundly reshapes our understanding of how the brain works.”

"A third study examined astrocyte activity in the brains of live fruit flies and found that these cells play an active role in regulating complex neuronal signaling networks. Because astrocytes are quite large, they can receive signals from thousands of neuronal connections at once. But instead of becoming overwhelmed, these cells pick and choose which neurons to listen to by switching off their ability to respond to neurotransmitters like dopamine and glutamate. The team found a similar mechanism in rodent brains, suggesting that it evolved early and has continued to be relevant for survival. “ If a tiger is behind you, you need to rapidly change how whole brain regions are thinking,” lead study author Kevin Guttenplan explains in a statement. “It’s time to shut out everything else on your mind and entirely focus the brain on escaping.”

"Together, these findings add to growing evidence that astrocytes play a much more active role in the brain than previously thought. The new studies should also change the way scientists think about “investigating neurological and psychiatric disorders that involve dysregulation of neuromodulation,” neuroscientist Cagla Eroglu writes in a related Science Perspective. She notes that disorders like depression, anxiety, and schizophrenia, which are traditionally attributed to neuronal dysfunction, “may stem from disrupted astrocyte signaling.'”

Comment: because the effect of astrocytes action is so indirect it was late in discovery. They were placed there for a reason and now that reason is now understood. From a design standpoint having systems for slower reactions makes perfect sense.

https://www.the-scientist.com/is-the-world-spinning-or-is-it-me-how-the-brain-distingui...

"In the 1860s, physician Hermann von Helmholtz did a simple experiment to understand how the world stays still during eye movements. With a still head, he closed one eye and swiveled the other to look around. Despite the rapid darting of the open eye, he noticed the image of the surroundings appeared stable rather than blurred. Next, instead of moving the eye naturally, he gently pushed it around in the socket with a finger and noticed the chaotic movement of the view. Why does the world shift when an external force is used to move the eye, but not when it swivels on its own?

"Von Helmholtz proposed that when an animal decides to move its eyes naturally, certain areas of the brain receive a duplicate of this command called the efference copy, which signals that the upcoming motion of the world is a result of eye movement and not actual shifting of the environment.1 This message is absent when an external force moves the visual field. “When the finger hijacks the movement, it takes away the efference copy and we see what happens in a world without one,” said Tomas Vega-Zuniga, a neuroscientist at the Institute of Science and Technology Austria (ISTA). The efference copy plays a crucial role in an animal’s ability to differentiate its own motion from that of the surrounding world, which in turn is essential for coherent perception and behavior.

***

"Now, researchers at ISTA have shown that a region of the thalamus, called the ventral lateral geniculate nucleus (vLGN), serves as an interface between visual and motor neural circuits and is responsible for correcting self-motion-induced blur. These findings in mice, published in Nature Neuroscience, could help researchers better understand how an organism’s senses faithfully represent the world and enable appropriate behavior.

'Visual perception is complex and requires seamless communication between different brain areas. One such region that integrates visual and other sensory perceptions with movement is the superior colliculus.4 This multi-layered structure receives visual information directly from the retina, as well as indirectly via the visual cortex. “The superior colliculus is like a map of the world. It knows where things are in space,” said Vega-Zuniga, a study coauthor. In previous experiments in primates, researchers showed that the superior colliculus sends signals to areas in the cortex that control eye movements. So, Vega-Zuniga and his colleagues hypothesized that neurons that send information to the superior colliculus could serve as a source of the efference copy and correct motion-induced blur.

"An important function of the efference copy is to block certain sensory inputs to maintain coherent perception for the organism. For example, auditory signaling in crickets is diminished during their own chirps, so as not to desensitize hearing at other times. Since this is achieved through suppression or inhibition, the team focused on the vLGN, which forms inhibitory connections with neurons in superior colliculus.

***

"They found that the vLGN neurons only responded to self-motion. Additionally, when the team blocked vLGN activity, the neuronal responses to eye movement in the superior colliculus became longer and more frequent, suggesting that the vLGN shortens the effective time of visual exposure during movement, thus reducing blur.

"To confirm this, Vega-Zuniga and his colleagues tested how well the mice could perceive depth, which not only requires both visual and movement perception, but is detrimentally affected by blurry vision. They observed that mice in which the vLGN output was blocked showed reduced avoidance of a cliff in the behavioral arena, demonstrating difficulty in judging depth. Based on this, the authors suggested that the vLGN is important for visual perception during self-generated movements."

Comment: since rapid movement is essential to survival this mechanism is essential. Assuming the new brain arrived as a blank slate this entire mechanism had to be learned. God designs for facility.

https://medicalxpress.com/news/2025-04-insight-human-motor-cortex-encodes.html

"Compared to other animal species, humans can plan and execute highly sophisticated motor tasks, including the ability to write complex characters using their hands. While many past studies have tried to better understand the neural underpinnings of handwriting and other complex human motor capabilities, these have not yet been fully elucidated.

***

"Researchers at Zhejiang University in China recently carried out a study aimed at further exploring the role of the human motor cortex in the encoding of intricate handwriting, such as Chinese characters. Their findings, published in Nature Human Behavior, suggest that this encoding unfolds via a sequence of stable neural states.

***

"'The experiment task was simple," explained Qi. "We asked our participant to write Chinese characters one by one, with the guidance of a video, just like a karaoke game for writing. We recorded single-unit MC neural activity from his motor cortex (MC) with two microelectrode arrays as he performed the handwriting task."

"The brain activity recordings gathered by the researchers provided new interesting insights into the underpinnings of handwriting, suggesting that the motor cortex encodes complex handwriting by breaking it into a series of small movement segments or states. In their paper, Qi and her colleagues hypothesize that these states are the primitive units of movement encoding.

***

"This recent work by Qi and her colleagues enriches the present understanding of how the human brain executes more advanced motor tasks that require high levels of precision. In the future, their findings could inform the development of new BCIs that allow users to write on a computer via their brain signals."

Comment: more evidence of how special we are

https://mail.google.com/mail/u/0/#inbox/FMfcgzQZVKDRSMzCWSBdLxPjsrlMVCJG

[Sabine again] "I want to talk about a group of researchers that looked at how humans can make decisions so quickly and now believe they have identified an essential ingredient to consciousness.

***

"Think about catching a ball mid-flight. Your brain figures out where the ball is going, predicts where it will land, and tells your muscles to move—all in a fraction of a second. Yet, the neurons that power this process are super slow. It takes 10 to 20 milliseconds for a signal to travel from one neuron to another. Today’s computers, for comparison, perform hundreds of billions, if not trillions, of operations per second. So how does the brain do it?

"The new study reveals that the brain’s secret lies in its ability to teeter on the edge of chaos. And not only this, they say that the mathematics of quantum physics is a surprisingly good description for consciousness.

"The “edge of chaos” is the range in which a system switches from orderly behaviour to a chaotic one. This transition regime is somewhat less poetically called the “critical” range and it’s where interesting things happen. The critical range is where emergent features develop and where complexity arises.

***

"This is the world that we live in: we seek a balance between order and chaos: This is what “criticality” means. And, here is the important bit, a critical system has long-range correlations, like those links between nations.

***

"...back to the brain. It’s also a complex system, so if the idea of the “edge of chaos” is correct, then the human brain must also linger in the critical range between order and chaos. It can probably switch from one to the other and use the long-range correlations that come with the transition.

"In the new paper now the authors say that this criticality is why the human brain can make surprisingly fast and accurate decisions even though the individual computational operations are so slow.

"The long-range connections of critical systems let different parts of the brain talk to each other. It’s not just fast but part of the reason why the human brain can function with so little power. Your average supercomputer needs at least MegaWatts of power, whereas the human brain runs on typically 20 Watts, that’s about what it takes to power a dim bulb.

"Wilder still, they say they used the mathematics of quantum mechanics to develop a model for what’s going on in the human brain, and that allowed them to quantify how “critical” the state of a brain is. They then used functional MRI brain scans from over 1,000 people, and found that using this measure for “criticality” they could tell apart people who were awake from those who were sleeping. It seems that “criticality” indeed tells us something about consciousness.

"What does it mean that they use the equations of quantum mechanics? I don’t know. They use these equations because, well, they work. They don’t know why. But I am pretty sure that it doesn’t mean that the human brain is a quantum computer.

"I think that AI researchers haven’t fully appreciated the relevance of criticality for the emergence of complexity. Because if that’s right it means that to get to consciousness, you need a system that can descend into chaos."

Comment: Remember the Penrose Hameroff theory that the brain has quantum actions in little tubules in the brain. If NDE theories are correct, this is how the brain must work to receive consciousness and use it. This article DOES NOT give us any new information. It is just very theoretical. But I find it reasonable to consider. If the universe at its base is quantum mechanics, it is no surprise the most complex item in the universe runs at a quantum level.

https://www.quantamagazine.org/intelligence-evolved-at-least-twice-in-vertebrate-animal...

"Humans tend to put our own intelligence on a pedestal. Our brains can do math, employ logic, explore abstractions and think critically. But we can’t claim a monopoly on thought. Among a variety of nonhuman species known to display intelligent behavior, birds have been shown time and again to have advanced cognitive abilities. Ravens plan(opens a new tab) for the future, crows count and use tools(opens a new tab), cockatoos open and pillage(opens a new tab) booby-trapped garbage cans, and chickadees keep track(opens a new tab) of tens of thousands of seeds cached across a landscape. Notably, birds achieve such feats with brains that look completely different from ours: They’re smaller and lack the highly organized structures that scientists associate with mammalian intelligence.

“'A bird with a 10-gram brain is doing pretty much the same as a chimp with a 400-gram brain,” said Onur Güntürkün(opens a new tab), who studies brain structures at Ruhr University Bochum in Germany. “How is it possible?”

***

"A series of studies published in Science(opens a new tab) in February 2025 provides the best evidence yet that birds and mammals did not inherit the neural pathways that generate intelligence from a common ancestor, but rather evolved them independently. This suggests that vertebrate intelligence arose not once, but multiple times. Still, their neural complexity didn’t evolve in wildly different directions: Avian and mammalian brains display surprisingly similar circuits, the studies found.

***

"Rather than neat layers, birds have “unspecified balls of neurons without landmarks or distinctions,” said Fernando García-Moreno(opens a new tab), a neurobiologist at the Achucarro Basque Center for Neuroscience in Spain. These structures compelled neuroanatomists a century ago to suggest that much of bird behavior is reflexive, and not driven by learning and decision-making.

***

"What he found was a surprise: The brain regions thought to be involved only in reflexive movements were built from neural circuits — networks of interconnected neurons — that resembled those found in the mammalian neocortex. This region in the bird brain, the dorsal ventricular ridge (DVR), seemed to be comparable to a neocortex; it just didn’t look like it

***

"They found that the mature circuits looked remarkably alike across animals(opens a new tab), just as Karten and others had noted, but they were built differently, as Puelles had found. The circuits that composed the mammalian neocortex and the avian DVR developed at different times, in different orders and in different regions of the brain.

***

"By comparing the bird pallium to lizard and mouse palliums, they also found that the neocortex and DVR were built with similar circuitry(opens a new tab) — however, the neurons that composed those neural circuits were distinct.

***

Taken together, the studies provide the clearest evidence yet that birds and mammals independently evolved brain regions for complex cognition. They also echo previous research from Tosches’ lab, which found that the mammalian neocortex evolved independently from the reptile DVR.

***

"Similarly, “there’s limited degrees of freedom into which you can generate an intelligent brain, at least within vertebrates,” Tosches said. Drift outside the realm of vertebrates, however, and you can generate an intelligent brain in much weirder ways — from our perspective, anyway. “It’s a wild west,” she said. Octopuses, for example, “evolved intelligence in a way that’s completely independent.” Their cognitive structures look nothing like ours, except that they’re built from the same broad type of cell: the neuron. Yet octopuses have been caught performing incredible feats such as escaping aquarium tanks, solving puzzles, unscrewing jar lids and carrying shells as shields."

Comment: same sort of intelligent action based on totally different brain organizations. Amazing.

https://www.sciencealert.com/new-study-identifies-unexpected-part-of-your-brain-thats-u...

"Our recent study may have brought us one step closer by taking a new approach – comparing the way brains are internally connected.

"We used publicly available MRI data of white matter, the fibres connecting parts of the brain's cortex. Communication between brain cells runs along these fibres. This costs energy and the mammalian brain is therefore relatively sparsely connected, concentrating communications down a few central pathways.

"The connections of each brain region tell us a lot about its functions. The set of connections of any brain region is so specific that brain regions have a unique connectivity fingerprint.

"In our study, we compared these connectivity fingerprints across the human, chimpanzee, and macaque monkey brain.

***

"Much of the previous research on human brain uniqueness has focused on the prefrontal cortex, a group of areas at the front of our brain linked to complex thought and decision making. We indeed found that aspects of prefrontal cortex had a connectivity fingerprint in the human that we couldn't find in the other animals, particularly when we compared the human to the macaque monkey.

***

"The feature driving this distinction was the arcuate fasciculus, a white matter tract connecting the frontal and temporal cortex and traditionally associated with processing language in humans. Most if not all primates have an arcuate fasciculus but it is much larger in human brains.

"However, we found that focusing solely on language may be too narrow. The brain areas that are connected via the arcuate fasciculus are also involved in other cognitive functions, such as integrating sensory information and processing complex social behaviour.

"Our study was the first to find the arcuate fasciculus is involved in these functions. This insight underscores the complexity of human brain evolution, suggesting that our advanced cognitive abilities arose not from a single change, as scientists thought, but through several, interrelated changes in brain connectivity.

"While the middle temporal arcuate fasciculus is a key player in language processing, we also found differences between the species in a region more at the back of the temporal cortex.

"This temporoparietal junction area is critical in processing information about others, such as understanding others' beliefs and intentions, a cornerstone of human social interaction.

"In humans, this brain area has much more extensive connections to other parts of the brain processing complex visual information, such as facial expressions and behavioural cues. This suggests that our brain is wired to handle more intricate social processing than those of our primate relatives. Our brain is wired up to be social.

"These findings challenge the idea of a single evolutionary event driving the
emergence of human intelligence. Instead, our study suggests brain evolution happened in steps. Our findings suggest changes in frontal cortex organisation occurred in apes, followed by changes in temporal cortex in the lineage leading to humans.

"Richard Owen was right about one thing. Our brains are different from those of other species – to an extent. We have a primate brain, but it's wired up to make us even more social than other primates, allowing us to communicate through spoken language."

Comment: finding this difference is not surprising. Connectivity is one form of complexification, another is an increased number of interconnected neurons. The human brain has more of both.

https://www.quantamagazine.org/the-mysterious-flow-of-fluid-in-the-brain-20250326/

"Incased in the skull, perched atop the spine, the brain has a carefully managed existence. It receives only certain nutrients, filtered through the blood-brain barrier; an elaborate system of protective membranes surrounds it. That privileged space contains a mystery. For more than a century, scientists have wondered: If it’s so hard for anything to get into the brain, how does waste get out?

***

"However, the brain’s blood vessels are surrounded by open, fluid-filled spaces. In recent decades, the cerebrospinal fluid, or CSF, in those spaces has drawn a great deal of interest. “Maybe the CSF can be a highway, in a way, for the flow or exchange of different things within the brain,” said Steven Proulx, who studies the CSF system at the University of Bern.

***

"A team at the University of Rochester led by the neurologist Maiken Nedergaard(opens a new tab) asked whether the slow pumping of the brain’s blood vessels might be able to push the fluid around, among, and in some cases through cells, to potentially drive a system of drainage. In a mouse model, researchers injected a glowing dye into CSF, manipulated the blood vessel walls to trigger a pumping action, and saw the dye concentration increase in the brain soon after. They concluded that the movement of blood vessels might be enough to move CSF, and possibly the brain’s waste, over long distances.

"The team took a further step in their interpretation. Because this kind of pumping — distinct from the familiar pulse from the heart — is regularly observed during sleep, they suggest that perhaps their observations can help explain why sleep feels refreshing. But it’s a hypothesis that not everyone agrees is well founded(opens a new tab). When it comes to ascribing purpose to the fluid moving through the brain, many researchers believe that the truth is still elusive.

"At the center of the brain are flooded caverns, like great cisterns shrouded in darkness, called ventricles. Cerebrospinal fluid seeps from the ventricle walls and then moves. Under pressure, it emerges elsewhere within the skull, flows down the neck and enters the spine.

***

“Everyone accepts that there must be some kind of flow here,” said Christer Betsholtz(opens a new tab), a professor of vascular biology at the Karolinska Institute in Sweden. “About half a liter of CSF is produced in the ventricles every day, and it has to get out. People are still fighting about where the cerebrospinal fluid gets out.”

***

"...Nedergaard, along with the neurologist Jeffrey Iliff(opens a new tab), then a postdoc in her lab, and their colleagues, injected a tracer into cerebrospinal fluid(opens a new tab) and watched it quickly arrive elsewhere. How did it get from one place to another? They proposed that the spaces around blood vessels commune with even smaller spaces deep in the brain, between individual cells. They also suggested that CSF moves through brain cells called astrocytes into those spaces. There, the fluid might drop off some molecules and pick up others; it may then wend its way back out to the spaces around blood vessels, and thence move waste out of the brain. All of this would have to be driven by a flow of uncertain mechanism.

***

"In a 2013 paper, her team wrote that there was more movement of cerebrospinal fluid in sleeping and anesthetized mice than in waking ones — and that perhaps during sleep CSF sweeps waste out of the brain. Maybe this “brainwashing,” as headlines described it, could provide one reason why sleep is necessary, and explain how much better we feel after a good night of it.

***

"In the years since those initial studies, a large number of papers(opens a new tab) referencing this brain-drainage theory, called the glymphatic hypothesis, have been published. It’s a catchy idea, but parts of the story raise red flags to some researchers who study the brain’s vasculature.

***

"According to Betsholtz, there is no evidence that fluid is moving into the spaces around blood vessels that leave the brain.

"But many other researchers appear to have accepted the glymphatic hypothesis. That’s because it fills a hole in our understanding of the brain, said Donald McDonald(opens a new tab), who studies blood and lymph vessels at the UCSF School of Medicine. Personally, he doesn’t feel that the theory holds water, but he acknowledges its popularity. It fits comfortably in the space where there is a mystery.

***

"For Nedergaard, Haugland and their collaborators, the findings tie together norepinephrine, the physical movement of blood vessels, and the flow of CSF in the brain. Nedergaard also asserts that the results are consistent with her group’s earlier finding that there is more brain drainage during sleep than during wakefulness.

***

“'It’s clear that the brain has and needs a waste clearance system. … It’s really interesting to explore what that is and how that works.'”

Comment: the brain floats in a liquid which is a very good way to protect it from blows to the skull. The CSF must pick up waste and remove it. We still don't know how. Such a intricate system must be designed.

https://www.sciencedaily.com/releases/2025/03/250306123254.htm

"A study led by Dr. Rodrigo Quian Quiroga,... has allowed scientists to observe for the first time how neurons in the human brain store memories independent of context in which they are acquired. Published in Cell Reports, the study confirms that neurons can distinguish objects or people regardless of their context, enabling the formation of higher and more abstract relationships, which constitutes the basis of human intelligence.

***

"The study led by Dr. Quian Quiroga has yielded "surprising responses" that contradict previous findings, as neuronal responses to a specific concept remain the same when the context changes, such as remembering having seen a person in different locations. "The basic principle of neuronal coding in humans is the opposite of what has been observed in other species, which has significant implications," notes Quian Quiroga.

***

"Patients were presented with two stories featuring the same person in different contexts, supported by images. Thanks to the monitoring of individual neurons while performing this task, researchers could observe which groups of neurons were activated and how they responded in the two stories. Specifically, they confirmed that if a neuron responded to a person's image, the response remained the same in both stories. Furthermore, when patients recounted the story themselves, the same neurons were activated seconds before they referred to the protagonist, and also in the same way for both stories.

"'Memories are stored in a much more abstract manner in humans compared to other animals. You can think of concepts or anything else in more abstract terms, independent of the context in which you learned them," explains Dr. Quian Quiroga, suggesting that this could be one of the "foundations of human intelligence." "This ability allows us to make much more abstract and complex associations and inferences than if we were forced to think of each concept within a specific, concrete context," he asserts. In other words, humans can decontextualize their memories to create more abstract thought.

Comment: we may pick apart mouse neurons and they will look like ours, but note the differential functions in groups of neurons.

https://evolutionnews.org/2025/02/split-brain-surgeries-reveal-reality-of-the-soul/

"Dr. Theodore Schwartz is a prominent Cornell University neurosurgeon. In addition to publishing many scholarly articles, he is the author of Gray Matters: a Biography of Brain Surgery (2024). He’s a very thoughtful guy and his recent essay at Psyche, “What removing large chunks of brain taught me about selfhood”, caught my attention.

"Dr. Schwartz: “As a brain surgeon…I’ve severed the brain in two and watched in amazement as my patients wake up feeling like their complete and undivided selves.” (February 17, 2025)

"I’ve had the same experience. After split-brain surgery, patients wake up feeling completely unified, like just one person, despite the surgical disconnection of the two halves of their brain. A few patients have transient disorders like “alien hand syndrome” but this is rare. By and large, these people are normal in ordinary activities of life.

"Dr. Schwartz: “When I first did this type of operation, I had fantasies that they might suddenly refer to themselves as ‘we’ rather than ‘I’. Thankfully, this never occurred…the patient’s sense of a unified self is the illusion.”

"The split-brain patient’s sense of a unified self is real, not an illusion.

I say this for two reasons.

"1. It makes no sense to say that two people have an illusion that they are one person. To have an illusion presupposes that the subject with the illusion is one person. Two people would have two illusions, or they would have similar illusions, or share illusions, or conspire to claim to have the same illusion, etc. But having an illusion — even an illusion that I am one person after having my brain split in two — presupposes that I am a single person that has the illusion. The claim that two people have one illusion — not just share similar illusions, in which case they are just two people with two similar illusions — makes no sense.

"2. There is clear neuroscientific evidence for unified consciousness in patients with split-brains. Neuroscientist Justine Sergent studied split-brain patients and found that while some perceptual abilities are indeed split — for example, the right side of the visual field is seen via the left hemisphere, and vice versa — there remains a genuine unity to the human mind. Sergent showed images of different objects to each of the two split hemispheres, and found that patients could compare the objects reasonably accurately, even though no part of the brain perceived both objects.

"From her paper: “[We found] the coexistence of perceptual disunity and behavioural unity, and they suggest that, even when the two disconnected hemispheres receive different information, the commissurotomized brain works as a single and unified organism.”

"Neuroscientist Yair Pinto and his colleagues, who extended Sergent’s work, found the same thing:... These findings suggest that severing the cortical connections between hemispheres splits visual perception, but does not create two independent conscious perceivers within one brain.

"Sergent and Pinto found that patients with split-brain surgery did have subtle perceptual disabilities associated with the split nature of their brains, but they nonetheless were capable of integrating the split information and remained one conscious individual.

"In other words, the normal sense that split-brain patients have that they are one person with one center of consciousness is not an illusion. They are, in fact, one person with one mind, even after splitting the brain hemispheres. This means that there is an aspect of the mind — “soul” is perhaps a better word here — that is not split by the neurosurgeon’s scalpel.

"Our conscious unity, even after split-brain surgery, is not an illusion. Each of us is a physical creature with a single spiritual soul, which is immaterial and cannot be split with a knife. This is not only the perennial teaching of the great religions, but the evidence of the best neuroscience."

Comment: a variety of patients with missing brain parts have been shown to have complete consciousness. No neurosurgeon has ever seen split consciousness in any patient with a split commissure

https://www.sciencedaily.com/releases/2025/02/250213143301.htm

"New research has revealed that birds, reptiles, and mammals have developed complex brain circuits independently, despite sharing a common ancestor. These findings challenge the traditional view of brain evolution and demonstrate that, while comparable brain functions exist among these groups, embryonic formation mechanisms and cell types have followed divergent evolutionary trajectories.

***

"Previous studies had identified the presence of shared excitatory and inhibitory neurons, as well as general connectivity patterns suggesting a similar evolutionary path in these vertebrate species. However, the new studies have revealed that, although the general functions of the pallium are equivalent among these groups, its developmental mechanisms and the molecular identity of its neurons have diverged substantially throughout evolution.

"The first study,...shows that while birds and mammals have developed circuits with similar functions, the way these circuits form during embryonic development is radically different. "Their neurons are born in different locations and developmental times in each species," explains Dr. García-Moreno, head of the Brain Development and Evolution laboratory, "indicating that they are not comparable neurons derived from a common ancestor." Using spatial transcriptomics and mathematical modeling, the researchers found that the neurons responsible for sensory processing in birds and mammals are formed using different sets of genes. "The genetic tools they use to establish their cellular identity vary from species to species, each exhibiting new and unique cell types." This all indicates that these structures and circuits are not homologous, but rather the result of convergent evolution, meaning that "they have independently developed these essential neural circuits through different evolutionary paths."

***

"The results show that birds have retained most inhibitory neurons present in all other vertebrates for hundreds of millions of years. However, their excitatory neurons, responsible for transmitting information in the pallium, have evolved in a unique way. Only a few neuronal types in the avian brain were identified with genetic profiles similar to those found in mammals, such as the claustrum and the hippocampus, suggesting that some neurons are very ancient and shared across species. "However, most excitatory neurons have evolved in new and different ways in each species," details Dr. García-Moreno.

***

"'Our studies show that evolution has found multiple solutions for building complex brains," explains Dr. García-Moreno. "Birds have developed sophisticated neural circuits through their own mechanisms, without following the same path as mammals. This changes how we understand brain evolution."

"'These findings highlight the evolutionary flexibility of brain development, demonstrating that advanced cognitive functions can emerge through vastly different genetic and cellular pathways.

"'Our brain makes us human, but it also binds us to other animal species through a shared evolutionary history," explains Dr. García-Moreno. The discovery that birds and mammals have developed neural circuits independently has major implications for comparative neuroscience."

Comment: we are all different in brain structure and function. Humans have HAR regions in their DNA driving our difference. Brain development varies in convergent ways. It seems the drive to evolve is present in every species.