Top Neuroscience Stories of 2025

Enjoy this roundup of some of the best neuroscience stories of 2025. They delve into psychedelics, the benefits of exercise for brain health, and more.

The brain is at the center of who people are, shaping how they think, feel, and move through the world. This year, the top neuroscience stories covered topics ranging from how microplastics build up in the brain to how psychedelics affect it. Catch up on a few standout neuroscience stories before we head into 2026.

Microplastics are an ever-present part of people’s lives, whether in the air they breathe or in the food they eat. Exposure to these compounds can lead to potential harm, but to what extent? Researchers from the University of New Mexico sought to see where microplastics accumulated in people. By analyzing organs from deceased individuals, the team found that microplastics and nanoplastics accumulated at especially high levels in brain tissue. Even more striking, liver and brain samples collected in 2024 contained significantly more plastic than those from 2016, hinting that environmental plastic exposure is rising fast. While the study links plastic buildup with certain health conditions, scientists stress that larger, more diverse studies are needed to understand what this plastic presence really means for human health.

Splashing cold water on your face can feel refreshing, but plunging your whole body into icy water is another story. Cold-water plunges have surged in popularity, with enthusiasts touting a range of health benefits, yet scientists remain cautious. There is some evidence that cold-water plunges can increase endorphins, dopamine, and serotonin, but researchers acknowledge that more studies need to be done. Alongside potential benefits come real risks: Humans are not built for extreme cold, and sudden temperature drops can sharply lower blood pressure or lead to hypothermia. As scientists continue to investigate, it’s important to remember that the effects of cold-water plunges can vary widely from person to person.

Alongside diet, lifestyle, environmental exposures, and genetics, metal levels in the brain are emerging as another factor that may contribute to Alzheimer’s disease. Imbalances in metals such as iron, copper, and zinc have long been linked to its pathology, but when researchers at Harvard Medical School analyzed metals in human brain tissue and blood, lithium caught their attention. They found that lithium deficiency was associated with early physiological changes. Building on this observation, the team tested the idea in a mouse model of Alzheimer’s disease, supplementing the animals’ diets with lithium. Mice fed a lithium diet had reduced expression of genes related to neurodegeneration and increased expression of genes related to learning and memory. Overall, the study pointed to lithium monitoring as a potential compass, helping researchers navigate toward clinically meaningful target levels in ongoing trials.

As babies explore the world, learning to crawl, walk, and even pick up their first language, they are constantly forming memories. Yet when adults try to recall these early experiences, they come up blank. This phenomenon, called infantile amnesia, has intrigued scientists for more than a century. The prevailing hypothesis suggested that the hippocampus, a brain structure that is crucial for forming episodic memories, is immature until adolescence. To test this idea, researchers at Yale University took a closer look at the infant hippocampus using functional magnetic resonance imaging and an image memory test. Their results suggest that infants as young as one year old can form episodic memories after all, providing further insight into this puzzling phenomenon.

From “magic mushrooms” to “acid,” psychedelics have long fascinated scientists and the public alike, promising profound changes in perception, mood, and even mental health. But behind the headlines and hype lies a far more complex scientific story. This feature explores what researchers actually know—and what remains uncertain—about how psychedelics affect the brain. It dives into evidence of how these drugs may temporarily enhance neural plasticity to emerging systems-level and cognitive neuroscience models that attempt to explain their wide-ranging effects. Still, much more research is needed to fully unravel the complex mechanisms through which psychedelics act on the brain.

Parkinson’s disease is among the fastest-growing neurological disorders, marked by the gradual loss of dopamine-producing neurons in the brain. Although it’s best known for affecting movement, Parkinson’s disease also takes a toll on mood, thinking, and sleep, turning everyday tasks into uphill battles. With no cure in sight, researchers, clinicians, and people living with the disease are looking for ways not just to cope, but to push back. One unlikely ally? Exercise. This feature follows how patients and scientists are putting aerobic activities like boxing, cycling, and dancing to the test and finding that breaking a sweat can boost mobility, lift mood, help protect dopamine-producing neurons, and even change how people approach life with Parkinson’s disease.