Frontal system: weather system where there is a line of separation between cold and warm air masses, usually associated with strong winds.

UNESCO: L O S S A R Y

When the pre-frontal cortex is fired up, the explicit system is usually turned on.

FORBES: Mind Hacks: How Innovators Really Arrive At Their Big Ideas

One of serotonin's jobs is to show growing nerve cells how they should connect from the frontal cortex, where reasoning takes place, to the limbic system, the seat of many emotional responses.

ECONOMIST: Diet and the unborn child