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Reaction Time experiments involves the presentation of a stimulus to which the subject is to respond as quickly as possible.  Reaction Time experiments typically collect data from the duration between the presentation of a stimulus and the execution of an action.  In addition, whether the response was correct is also noted.

We can group Reaction Time experiments into two very basic camps: Basic reaction time and Choice reaction time.  Basic reaction time experiments measure your reaction time to the presentation of a simulus without your having to make decisions regarding the nature of the stimulus.  For example, a picture may appear on the screen at random intervals in time.  In a simple reaction time experiment, your task is to hit some key or button as fast as you can upon appearance of the picture.

Choice reaction time experiments involve, in addition to reacting to the presentation of a stimulus, your descriminating some defining characteristic of that stimulus.  For instance, the signal might be a letter, so it would be your task to say the name of the letter (or, as would be the case with on-line experiments, hit the appropriate letter key).

In the following, you will be presented with two experiments.  The first experiment is a simple reaction time experiment.  Here you will be presented with a sequence of stimulae, at randomly varying intervals of time.  Your task is simply to hit the space bar as quickly as you can upon presentation of each stimulus.