Reaction time

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For Ian Lowe's book, see Reaction Time (book).

Reaction time (RT) is the elapsed time between the presentation of a sensory stimulus and the subsequent behavioral response. RT is often used in experimental psychology to measure the duration of mental operations, known as mental chronometry. The behavioral response is often a button press but can also be an eye movement, a vocal response, or some other observable behavior.

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[edit] Types of RT tasks

  • Simple reaction time is usually defined as the time required for an observer to detect the presence of a stimulus. For example, an observer might be asked to press a button as soon as a light or sound appears. Mean RT is approximately 180 to 200 milliseconds to detect visual stimuli, whereas for sound it is around 140-160 milliseconds.[1]
  • Go/No-Go reaction time tasks require that the observer press a button when one stimulus type appears and withhold a response when other stimulus types appear. For example, the observer is to press the button when a red light appears and not respond when a green light appears.
  • Choice reaction time tasks require distinct responses for each possible class of stimulus. For example, the observer may be asked to press one button if a red light appears and a different button if a yellow light appears.

[edit] History

Abū Rayhān al-Bīrūnī was the first to describe the concept of reaction time:[1]

"Not only is every sensation attended this by a corresponding change localized in the sense-organ, which demands a certain time, but also, between the stimulation of the organ and consciousness of the perception an interval of time must elapse, corresponding to the transmission of stimulus for some distance along the nerves."

Franciscus Donders was among the first to systematically analyze human RT to measure the duration of mental operations.

[edit] See also

Mental chronometry

[edit] References

  1. ^ Iqbal, Muhammad, “The Spirit of Muslim Culture”, The Reconstruction of Religious Thought in Islam, <http://www.allamaiqbal.com/works/prose/english/reconstruction>. Retrieved on 25 January 2008 

[edit] External links

Simple Reaction Time:

Simple Reaction Time Tests: (note that the hardware/software setup will greatly affect measurements making the scores largely incomparable from user to user)

Complex Reaction Time: