New study identifies part of brain animals use to make inferences

Animals survive in changing and unpredictable environments by not merely responding to new circumstances, but also, like humans, by forming inferences about their surroundings—for instance, squirrels understand that certain bird noises don't signal the presence of a predator, so they won't seek shelter when they later hear these same sounds. But less clear is how the brain works to create these inferences.

In a study published in the journal Neuron, a team of  researchers identified a particular part of the brain that serves as an "inference engine." The region, the orbitofrontal  cortex (OFC), allows animals to update their understanding of their surroundings based on changing circumstances.

To survive, animals cannot simply react to their surroundings. They must generalize and make inferences—a cognitive process that is among the most vital and complicated operations that nervous systems perform. These findings advance our knowledge of how the brain works in applying what we've learned.

The scientists add that the results offer promise for better understanding the nature of neuropsychiatric disorders, such as bipolar disorder and schizophrenia, in which our ability to make inferences is diminished.

In the experiments conducted when the brain's OFC was disrupted, the trained rats could no longer update their understanding of what the other available rewards might be—specifically, they couldn't make distinctions among hidden states.

These results, based on recordings of more than 10,000 neurons, suggest that the OFC is directly involved in helping the brain make inferences in changing situations.

Learning to see after being born blind: Brain imaging study highlights infant adaptability

Some babies are born with early blindness due to dense bilateral congenital cataracts, requiring surgery to restore their sight. This period of several months without vision can leave a lasting mark on how the brain processes visual details, but surprisingly little on the recognition of faces, objects, or words. This is the main finding of an international study conducted by neuroscientist.

Using brain imaging, the researchers compared adults who had undergone surgery for congenital cataracts as babies with people born with normal vision. The results are striking: in people born with cataracts, the area of the brain that analyzes small visual details (contours, contrasts, etc.) retains a lasting alteration from this early blindness.

On the other hand, the more advanced regions of the visual brain, responsible for recognizing faces, objects, and words, function almost normally. These "biological" results have been validated by computer models involving artificial neural networks. This distinction between altered and preserved areas of the brain paves the way for new treatments. In the future, clinicians may be able to offer visual therapies that are better tailored to each patient.

Babies' brains are highly adaptable . Even if vision is lacking at the very beginning of life, the brain can adapt and learn to recognize the world around it even on the basis of degraded information.

These findings also challenge the idea of a single "critical period" for visual development. Some areas of the brain are more vulnerable to early vision loss, while others retain a surprising capacity for recovery. The brain is both fragile and resilient. Early experiences matter, but they don't determine everything.

Impact of a transient neonatal visual deprivation on the development of the ventral occipito-temporal cortex in humans, Nature Communications (2025).

https://www.nature.com/articles/s41467-025-65468-7#:~:text=We%20sho...

Frozen RNA survived 50,000 years
Researchers have found the oldest RNA molecules to date in mummified woolly mammoth tissue. RNA is a fragile molecule, which makes intact ancient samples few and far between. But such samples are sought after because analysing ancient RNA could shed light on the gene activity of extinct animals. Scientists used enzymes to convert RNA in the mammoth tissue to DNA, and then reverse-engineered the original RNA sequences. This technique recovered fragments of RNA from three samples, dated to between 39,000 and 52,000 years old.

https://www.cell.com/cell/fulltext/S0092-8674(25)01231-0?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0092867425012310%3Fshowall%3Dtrue

https://www.science.org/content/article/forty-thousand-year-old-mam...