Efficiency of information processing to include:: Simple reaction time.

The idea

Simple reaction time is the time taken to initiate a single, pre-programmed response to one known stimulus, with no decision about which response to make. In AQA A-level Physical Education, it is studied within the efficiency of information processing. The performer detects the stimulus, such as a starting gun, and executes the one learned action, such as driving out of the blocks. Because there is only one stimulus and one possible response, the decision-making load is minimal, so simple reaction time is typically shorter than choice reaction time. It is assessed through multiple-choice questions that require you to identify the definition, give a sporting example, or explain why a sprinter's start involves simple rather than choice reaction time.

What earns the marks

• Defines simple reaction time as the time from the onset of a single known stimulus to the initiation of the one required response.
• States that there is only one stimulus and only one possible response, so no response-selection decision is needed.
• Recognises that simple reaction time is typically shorter than choice reaction time because processing demands are lower.
• Applies the concept to a suitable example, such as a sprinter reacting to the starting gun by driving out of the blocks.
• Distinguishes simple reaction time from reaction time in general, which can include situations with more than one stimulus or response.

Common mistakes and how to put them right

• Confusing simple reaction time with choice reaction time.

  Put it right: Simple reaction time involves one stimulus and one response, whereas choice reaction time involves selecting between multiple stimuli or responses.

• Thinking that simple reaction time includes movement time.

  Put it right: It ends when the response is initiated, not when the action is completed.

• Assuming that simple reaction time is always the same for every performer.

  Put it right: It varies with factors such as arousal, fatigue, attention and practice.

• Believing that a fast simple reaction time guarantees a fast whole-body movement.

  Put it right: Reaction time and movement time are separate components of performance.

Exam tips

• Read the question carefully to check whether it asks about simple reaction time, choice reaction time or reaction time in general.
• When giving a sporting example, name the single stimulus and the single response explicitly, for example the starting gun and the sprint start.
• Use the phrase 'one stimulus, one response' as a quick check that your chosen example really is simple reaction time.