A gaze vector of a human subject is translated to a targeting vector that defines focus within a graphical user interface. Sensor data is received from a sensor system indicating pitch angle of a head of the human subject defining the gaze vector. The pitch angle is translated to a scaled pitch angle according to a pitch scaling function that increases amplification of the pitch angle in one or more directions as the pitch angle exceeds a start angle threshold in each of the one or more directions. The scaled pitch angle is output as a component of the targeting vector.