A study published in Nature Communications reports that a key function of the anterior cingulate cortex (ACC) is to help the brain adapt to performing new tasks. When the researchers changed the rules of a task requiring rats to perform an additional task in addition to a primary task, they found that a pair of regions on the brain’s ACC work together to influence the rats’ adaptive behavior. The study suggests the ACC detects and regulates decision making processes and updates cells in the motor cortex (M2) to adjust the task behavior.
The researchers observed the ACC’s role in guiding M2’s sequential decisions by manipulating ACC cell activity. At first, the rats had to poke their snout into just one hole to gain a little reward, and then they had to poke their nose into a sequence of two holes. Rats with silenced ACCs took longer to realize the rule change compared to rats with normal ACC activity. The electrical activity of cells in M2 were activated by different task rules such as adding an additional step.
The researchers also observed populations of neurons that responded to positive outcomes (reward for doing the task right) and negative outcomes (not getting a reward for doing the task wrong). Silencing the ACC increased the activity of the negative-outcome encoding neurons during negative. Optogenetics or the technique using flashes of light was used to control when the ACC went offline. The study found that if the researchers silenced the ACC after an incorrect choice and the rule change from one to two steps, ACC suppression could cause the rats to continue to err. Optogenetic silencing of the ACC after a correct choice did not significantly impact the rat’s behavior.
Previous studies have demonstrated that the brain can rewire itself. University of California San Francisco (UCSF) researchers used 2-photon microscopes to observe how brain circuits adapt to changing sensory input. Further studies on the role of ACC in managing new tasks can help identify strategies to prevent neurodegeneration.
Source: Nature Communications