Moving icons as a human interrupt

This report describes an experiment designed to test the use of simple linear motion as an attention-getting device for computer displays. The experiment involved two tasks: a primary task that required the typed transcription of a document onto a computer screen, and a secondary task that involved detecting and responding to a moving icon signal. The icon consisted of a rectangular bar that grew and shrank in an oscillatory fashion, as the top edge ascended and descended. The amplitude and the velocity of motion were varied systematically and the effect on response time was measured. The results from this secondary task show that there is an inverse relation between the velocity of the moving icon and the response time. No effect was found for amplitude. The speed of the responses suggests that simple motion is an effective attention-getting device for events in the periphery of the visual field.