Posner cueing task

Formulated by Michael Posner,[1] it assesses a person's ability to perform an attentional shift.

To measure reaction time (RT), a response mechanism is placed in front of the observer, usually a computer keyboard which is pressed upon detection of a target.

An exogenous cue can also be an object or image in the periphery, a number of degrees away from the centre, but still within the visual angle.

In this case, the arrow pointed to the right (directing attention to the right), but the stimulus in fact appeared in the box on the left.

[1] The observer learns that usually the cue is valid, reinforcing the tendency to direct attention to the cued side.

Since the participant is not allowed to move their eyes in response to the cue, but remain fixated on the centre of the screen, differences in reaction time between target stimuli preceded by these three cue conditions indicates that covert orienting of attention has been employed.

The ratio makes it beneficial for a participant to covertly shift attention towards the cued location, as it would be an accurate predictor for the majority of the time, giving rise to quicker target detection and response.

[3] When we attend to a location, even without directly looking at it, it facilitates processing and decreases the time we need to respond to information occurring in that given space.

This results in decreased reaction times in Posner's spatial cueing task for validly cued targets,[3] and slower reaction times in response to invalidly cued targets: "Detection latencies are reduced when subjects receive a cue that indicates where in the visual field the signal will occur" (Posner, Snyder & Davidson, 1980).