View an animated GIF of this scene. Ripley finds the alien in the shuttle. View an animated GIF of this scene. Nearly all viewers know that horror and thriller films might contain startle effects. There is an obvious utility to monitoring the flux of proximate objects, of which none are completely stable, predictable, safe.
Location constantly evolves relative to a perceiver.
Meanwhile, conscious attention is preoccupied with narrow and new concerns. This is where the cognitive uncanny and startle come in. Comparing affectively charged startle effects with weaker ones exposes how the weaker effects may develop too slowly to surprise competent, adult viewers. Sticking with the example at hand, first-time viewers very likely are surprised by the intensity of the visual and auditory stimulus of the Jonesey startle. The viewer's overall sense of a scene's speed is affected by cutting rate as well as the degree and type of movement of objects within the frame.