When we learn new a new task or a new nugget of information, our brain cells form new patterns of connections. This is the essence of learning. But what researchers have just found is that when brain cells form new connections, they are stronger when there is a “neighbor” close by.

The research team had mice learn a new motor task, like putting their paws through a slot to gain access to a morsel of food. They looked at what was going on in the motor cortex, which controls motor movements, specifically focusing on the “spines” of the cells’ dendrites, the parts of the neurons that form synapses (cell-cell connections) with other neurons.

The new synapses that were forming tended to form in clusters. Moreover, the spines grew stronger – which makes for a better synaptic connection – when there was another one nearby.

During the few days when the mice were learning and repeating the new behavior, some interesting changes took place in the cells of the motor cortex. The new synapses that were forming tended to form in clusters. Moreover, the spines grew stronger – which makes for a better synaptic connection – when there was another one nearby.

"We found that formation of a second connection is correlated with a strengthening of the first connection, which suggests that they are likely to be involved in the same circuitry,” said lead author Yi Zuo in a news release.  "The clustering of synapses may serve to magnify the strength of the connections.”

When mice later learned a different, but related task (like grabbing a piece of pasta instead of a seed), the brain still formed clusters, but the ones involved in the different tasks remained separate. This suggests that each task forms its own clustered connections that stay in separate brain circuits. "Repetitive activation of the same cortical circuit is really important in learning a new task,” said Zuo.

Previous research has shown that practice does indeed help us learn new tasks. This study adds to our understanding of the learning process by showing exactly what’s going on in the brain to explain why repetition improves learning. Still, mixing up one’s practice routine is also crucial to learning, since it challenges the brain to attack the task from different angels. Taking a break after you learn something new can also help solidify memories.

The researchers of the current study hope that understanding learning on the tiniest level will allow them to “find out the best way to induce new memories,” which could help not only in physical tasks but also in absorbing new information in general.

The study was published in the journal Nature.