In an exemplary embodiment, a system is provided that includes one or more first sensors, one or more second sensors, and a processor disposed onboard a vehicle. The first sensors are configured to at least facilitate obtaining first sensor data with regard to an external environment outside the vehicle. The second sensors are configured to at least facilitate obtaining second sensor data with regard to one or more eyes of a driver of the vehicle. The processor is configured to at least facilitate: determining a predicted gaze angle of the one or more eyes of the driver based on the external environment outside the vehicle, using the first sensor data; determining a measured gaze angle of the one or more eyes of the driver, using the second sensor data, and controlling one or more vehicle actions based on a comparison of the predicted and measured gaze angles.