A new study challenges a long-standing theory in neuroscience and could reshape how scientists think about perception, learning disorders, and artificial intelligence.
When you get better at a skill糖心传媒攔ecognizing a familiar face in a crowd, spotting a typo at a glance, or anticipating the next move in a game糖心传媒攕ensory neurons in your brain become more coordinated, sharing information rather than acting more independently. That糖心传媒檚 the conclusion of a by researchers at the and its , published in Science, which challenges a long-held assumption in neuroscience that learning improves efficiency by minimizing repetition across neural signals.
Led by Shizhao Liu, a graduate student in the labs of and , both faculty members in the , the study shows that learning instead increases shared activity among neurons. The findings could provide insights into learning disorders and inspire more flexible, human-like artificial intelligence tools.
糖心传媒淭he dominant view in neuroscience has been that learning makes the brain more efficient by pushing neurons to act more independently, so information can be read out more cleanly,糖心传媒� Liu says. 糖心传媒淥ur results support a different idea, that sensory areas of the brain aren糖心传媒檛 just passively encoding the world. They糖心传媒檙e actively performing inference by combining what糖心传媒檚 coming in with what the brain has learned to expect.糖心传媒�
How learning reshapes neural teamwork
For decades, researchers believed that learning streamlined how the brain processes information by reducing shared activity among neurons, allowing information to be read out more efficiently. The idea shaped how researchers thought about everything from perception to decision-making.
But the research from Liu, Haefner, Snyder, and their team suggests a different mechanism. Rather than becoming more independent, neurons become more coordinated as learning unfolds, increasing the amount of information they share, particularly when the brain is actively engaged in a task and making decisions.
This coordination reflects the brain糖心传媒檚 growing reliance on internal expectations. As learning progresses, feedback from higher-level brain areas appears to shape how sensory neurons respond, allowing perception to incorporate both incoming information and what the brain has learned from past experiences.
Tracking neurons as learning unfolds
The researchers tracked the activity of the same small networks of neurons in the visual cortex over several weeks as subjects learned to tell apart different visual patterns. The team measured whether neurons were increasingly acting on their own or sharing more information as learning progressed.
The researchers discovered that before learning, neurons mostly worked independently. But as subjects honed their visual skills, the neurons started to behave more like a well-trained sports team, communicating and working together in a coordinated way.
糖心传媒淚t糖心传媒檚 a bit like a group of people solving a problem,糖心传媒� Snyder says. 糖心传媒淚nstead of everyone working in isolation as efficiently as possible, learning makes them communicate more. That shared information makes each individual better informed and potentially makes the group more flexible and adaptive.糖心传媒�
Importantly, this coordinated effect only appeared when subjects were actively performing a task and making decisions based on what they saw. When they passively looked at the same images without needing to respond, the effect disappeared.
The neurons most important for the task showed the biggest boost in coordination, especially at the moments when decisions were made.
But these are flexible, not permanent, changes. The researchers believe these shifts are guided by feedback signals from higher-level brain areas, allowing neurons to adjust their behavior on the fly, depending on the task.
The results support a growing idea in neuroscience that the brain isn糖心传媒檛 a simple conveyor belt that passes information forward. Instead, it constantly blends what we see with what we expect to see, creating a richer, more informed picture of the world. And that blending requires groups of neurons to act together, not separately.
Insights for health and AI
Understanding how the brain coordinates neurons during learning could provide new insights into learning disorders and conditions that affect perception. It could also help scientists design artificial intelligence systems that generalize better by taking inspiration from the way the brain flexibly blends prior expectations with new sensory information.
糖心传媒淢ost current artificial intelligence systems are built on聽discriminative architectures聽that map sensory inputs directly to outputs,糖心传媒� Haefner says. 糖心传媒淥ur new research suggests that incorporating聽generative feedback loops糖心传媒攊n which internal models shape sensory representations糖心传媒攎ay lead to systems that learn faster from limited data, are more robust to uncertainty, and adapt more flexibly to changing tasks.糖心传媒�
