The effects of a task-irrelevant visual event on spatial working memory.

In the present experiment, we investigated whether the memory of a location is affected by the occurrence of an irrelevant visual event. Participants had to memorize the location of a dot. During the retention interval, a task-irrelevant stimulus was presented with abrupt onset somewhere in the visual field. Results showed that the spatial memory representation was affected by the occurrence of the external irrelevant event relative to a control condition in which there was no external event. Specifically, the memorized location was shifted toward the location of the task-irrelevant stimulus. This effect was only present when the onset was close in space to the memory representation. These findings suggest that the "internal" spatial map used for keeping a location in spatial working memory and the "external" spatial map that is affected by exogenous events in the outside world are either the same or tightly linked.