November 30, 2020
Microscopy images of neurons in mouse brain colored red and green

Researchers traced circuits from the ACC to the visual cortex (VC). VC neurons labeled green trace back to the caudal ACC, while neurons labeled red trace to the rostral ACC. Image credit: Sur Lab, MIT Picower Institute

When riding your bike to the store you might have two very different reasons to steer: plain old reflex when you see something dart into your path, or executive control when you see street signs that indicate the correct route. A new study by MIT neuroscientists shows how the brain is wired for both by tracking the specific circuits involved and their effect on visually cued actions.

The research, published in Nature Communications, demonstrates in mice that neurons in the anterior cingulate cortex (ACC) area of the prefrontal cortex, a region at the front of the brain associated with understanding rules and implementing plans, projects connections into an evolutionarily older region called the superior colliculus (SC). The SC carries out basic commands for reactive, reflexive movement. A key finding of the study is that the purpose of the ACC’s connections to the SC is to override the SC when executive control is necessary.