Inhibitory tagging system facilitates visual search.

Two visuospatial phenomena, serial search and inhibition of return, have recently gained the attention of scientists from such diverse disciplines as neuroscience, artificial intelligence and cognitive psychology. A linear increase in search latency with increasing display size has been assumed to reflect serial focused attention to each item in the display. A delay in the detection of a signal in a previously attended location has been assumed to reflect an inhibitory process that may be used to prevent attention from returning to the same stimulus. The following study of human performance supports these assumptions and, by demonstrating that inhibition of return operates in serial search, presumably to improve search efficiency, provides a functional link between these two phenomena.