NATURE OF EXERCISE:
Binary Choice Reaction Time is another complex reaction time challenge, which uses more of the cognitive process than Recognition Reaction Time (Exercise 2), which in turn uses more cognitive process than Simple Reaction Time (Exercise 1 series). Instead of simply responding to the presentation of a stimulus, Binary Choice Reaction Time requires the user to respond in a different fashion to each of two different stimuli. To make this exercise even more challenging, upon the random on-screen appearance of the word REVERSAL, you must give the reverse of the correct answer. This shift in momentum, called "task shifting" in psychology, or mental flexibility in real life, actually requires high order cognitive processing to perform quickly.

RELEVANCE TO EVERYDAY LIFE:
Choice reaction time exercises develop your ability to make decisions quickly and move on to the next problem. These exercises tend to be a favorite of both students and businessmen. Students have reported such exercises improve their test-taking ability (think in terms of timed examinations such as SATs and GMATs). Businessmen find choice reaction time exercises improve their productivity by allowing them to complete more decision cycles per day.

INSTRUCTIONS:
A horizontal display is presented. When the green light (which is always on the right side) appears, press the RIGHT ARROW key on your keyboard as quickly as possible. When the red light (which is always on the left side) appears, press the LEFT ARROW key on your keyboard as quickly as possible. If the word REVERSAL appears, then press the LEFT ARROW key for green or the RIGHT ARROW key for red. You must respond correctly 20 times to complete the exercise.