What do they mean when the day the patient is riding the vent?

I work in NICU and here people mention that the patient is riding the vent while looking at the screen? What do they mean by this and what are they looking at?

[chare]

That the patient is not triggering any of the breaths.  While it varies depending on which ventilator your unit uses, there should an indicator displayed on the screen to indicate a patient triggered breath.