Chapter 1. Spatial Cuing

1.1 Introduction

How fast can you respond to a target? That is the question that will be examined in this experiment. The target will be to one side or another of where you look. You are not to move your eyes. Keep looking straight ahead. Before each trial there will be a signal giving you some information about where the target is likely to be. An arrow will point in the direction where the target will be 80% of the time. A dashed line tells you that the target has a 50% chance of being to either side. You are to respond as quickly and accurately as you can. Do not anticipate the occurrence of the target.

1.2 Experiment Setup

1.3 Instructions

You will need to press the space bar to begin the experiment. At the beginning of the first trial, a fixation mark will appear. Please look at this mark. After it is removed, there will be a cue. The cue will be an arrow or a horizontal line as shown below:

If the cue is an arrow, the stimulus, a red oval, will be presented in the direction the arrow points 80% of the time. For example, if the arrow points to the right, the stimulus will be to the right 80% of the time. If the cue is the horizontal line, the stimulus will be to the right 50% of the time or to the left 50% of the time.

Your job is to respond to the stimulus when it appears as quickly as you can, without anticipating the stimulus. Press J to indicate when the stimulus has appeared.

Keyboard Response

1.4 Experiment

1.5 Results

1.6 Debriefing

There are many aspects of attention; one is selective attention. The fact that we select part of the world to attend to means that the other parts of the world, even though they make up most of the world, are ignored. In the visual domain, you can think of selective attention as a window that defines the region of the world from which we are receiving information. Or we can use the flashlight metaphor: What falls within the flashlight’s beam is what we attend to, and what falls outside is not processed.

This experiment is designed to examine our selective attention and how we can direct it to different locations. In this experiment, there were three conditions that were tested: valid (target occurs in the direction the arrow pointed), neutral (a horizontal line preceded the target), and invalid (target occurs on the opposite side from where the arrow pointed). The reaction time is faster in the valid condition and slowest in the invalid condition. Often we move our eyes to change the direction of our attention. The high acuity fovea is specialized for our more detailed vision. However, for simple responses such as the presence or absence of a target, we do not need to move our eyes. In this experiment, the stimuli occurred quickly and you were instructed not to move your eyes. So it is not the movement of the eyes that determines the outcome of this data, but the movement of attention. When attention is directed towards the target, we respond more quickly to that target. Thus, attention plays a key role in how fast we can respond to any incoming stimuli. If attention is directed away, we respond more slowly. One application of this knowledge in the everyday world is to realize that with increasing technology available to us while we drive, we risk responding more slowly to the stimuli we need to drive safely.

References:

Posner, M. I. (1980). Orienting of attention. The Quarterly Journal of Experimental Psychology, 32(1), 3-25.

Posner, M. I., Snyder, C. R., & Davidson, B. J. (1980). Attention and the detection of signals. Journal of Experimental Psychology: General, 109(2), 160-174.

1.7 Quiz