MIT News breed · Wetenschap

Flexible brain circuits can switch between different tasks

Neuroscientists have discovered circuits in the prefrontal cortex that can be repurposed to store different types of information, supporting the theory of reusable cognitive modules.

In a new study of mice, MIT neuroscientists have found the first evidence for the existence of these flexible modules. They identified neurons in the prefrontal cortex that can be used to store either a sensory input or an action plan in working memory. The brain uses the same populations of neurons to perform the same computation on different kinds of information, meaning the same subset of neurons can hold both an action and a sensory stimulus in working memory.

This discovery supports the theory that reusable circuits allow the brain to mix and match components to generate a rich variety of behavior. Researchers trained mice on a task where they had to determine if two sensory stimuli were the same and respond accordingly. They recorded electrical impulses from the brain, focusing on the prefrontal cortex and parietal cortex.

Within the parietal cortex, neurons exclusively stored memory of the tone. However, in the prefrontal cortex, a cluster of neurons switched between storing a memory of the first tone and remembering the plan of action for the second part of the task. Re-using these clusters for different purposes allows the animals to flexibly store different types of information.

The findings suggest that the same computational circuits can be used for different purposes, meaning a circuit that maintains items in working memory can hold either sensory or motor information and be flexibly reused depending on the current task. This eliminates the need to build an entirely new circuit for holding information each time a new task is learned.

AI-samenvatting op basis van de bron.