10 Mind-Blowing Brain Discoveries from 2025

The 10 most breathtaking discoveries about the brain in 2025

By Allison Parshall edited by Andrea Thompson

The human brain has 86 billion neurons connected by approximately 100 trillion synapses, making it one of the most complex objects in the known universe. Every year, neuroscientists make fascinating, important, and downright strange discoveries about how this resilient structure works, and 2025 did not disappoint. Here are 10 of this year’s most fascinating brain discoveries for your own brain to ponder.

The tour of eras

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Brain scans of thousands of people have revealed that the human brain has five distinct eras, with turning points in how it is organized occurring at ages nine, 32, 66 and 83. At each of these stages – for example, the “adolescent” period between ages nine and 32 – people’s brains tend to undergo the same types of changes.

Missing memories

You don’t remember being a newborn or even a toddler. Adults’ earliest memories tend to begin around kindergarten and no earlier. But recent research suggests that your brain was creating memories back in the day; you just don’t have access to it now. A study of the infant hippocampus, a deep brain structure crucial for memory formation, found that it can store memories once babies are about a year old, although it’s unclear why we can’t remember them when we grow up.

Unraveling Alzheimer’s Disease

The researchers also discovered another peculiarity of the brains of newborns: they contain very high levels of a protein that, in adults, indicates Alzheimer’s disease. Tau proteins help stabilize the structure of brain cells, but they can undergo chemical changes that cause them to become tangled, a process linked to Alzheimer’s disease. The fact that the brains of healthy newborns have high levels of these proteins, which subsequently decline, suggests that these harmful changes in adults could be avoided or reversed.

A neuron is born

Neuroscientists have long believed that we are born with all the neurons we will ever have. But evidence has slowly accumulated suggesting that adults can form new neurons, a process called neurogenesis. So far, the evidence has been mostly circumstantial (and controversial). But this year, researchers discovered newly formed neurons and the precursor cells that gave rise to them in the brains of adults, some as old as 78 years old. The findings “should finally put an end to this,” said a neurobiologist who was not involved in the research.

Reality check

When you imagine an apple, your brain activity isn’t that different from what you actually see. So how does your brain know the difference? Scientists have discovered a “reality signal” generated by a region of the brain called the fusiform gyrus, which is then evaluated by another region to determine whether something is real or imaginary. Researchers believe that dysfunction in this system could lead to hallucinations, in which people mistake something generated by the brain for something real.

Huntington’s hopes

Initial results from a clinical trial have shown that a drug called AMT-130 slows the progression of Huntington’s disease. If approved by regulators, it will be the first treatment for this rare genetic neurological disease that actually treats the disease itself, not just the symptoms. The treatment works by delivering the drug directly into the deep brain during an eight- to 10-hour surgical procedure.

Primate illumination

The human brain is special. Yet much of what scientists thought that differentiated us from other animals has been gradually eroded by the evidence. This year, scientists have learned more about the cognitive abilities of our closest primate relatives. Chimpanzees, for example, can evaluate evidence to update their beliefs when they turn out to be false, a kind of rational thinking. And bonobos can detect when a human doesn’t know something – an ability called theory of mind.

Beyond the rainbow

Our brain constructs colors based on the activation of cells in our retina that sense blue, green, and red light. Due to a biological quirk, there is no light on Earth that can activate. only cells detecting green light. But researchers managed to do just that by lasering the eyes of five participants to create an impossible new color that scientists called olo: an extremely saturated blue-green that exists beyond our normal visual range.

Bright brain

Did you know that your brain glows? Living tissues emit light called biophotons as a byproduct of energy use – and the brain uses a lot of energy. In a recent experiment, scientists detected for the first time biophotons emitted by the human brain from outside the skull. The show changed as people performed different mental tasks, but it remains to be seen whether these photons play a role in cognition.

The big question

The greatest mystery of the brain is how it creates consciousness. How does the activity of tens of billions of neurons create your experience of the world? Scientists have many theories about consciousness, and two of them recently faced off in a scientific face-off. The results have been extremely mixed, calling into question some of the central tenets of both theories and highlighting how much mystery remains in the quest to understand our minds.

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