Explain the information-processing model - input, decision-making, output and feedback - and the factors that influence reaction time and decision speed.

What this dot point is asking

You must explain the stages of information processing and the factors that influence how quickly and accurately a performer responds.

The information-processing model

Movement decisions follow a sequence:

• Input (sensory): the performer gathers information through vision, hearing, touch and proprioception (the sense of body position). There is far more information than can be used.
• Selective attention: the brain filters the relevant cues (the ball, the opponent) from the irrelevant (the crowd). Skilled performers attend to the right cues.
• Decision-making (central processing): the relevant information is compared with stored experience in memory to choose a response.
• Output (effector): signals are sent to the muscles to carry out the movement.
• Feedback: intrinsic and extrinsic feedback returns to the system to judge success and inform the next decision.

Memory and decision-making

Memory drives the decision stage.

• Short-term sensory store holds incoming information very briefly; selective attention decides what passes on.
• Short-term memory (working memory) holds a small amount of information for a few seconds while a decision is made.
• Long-term memory stores well-learned movement patterns (motor programs) almost permanently, so practised skills can be selected quickly and automatically.

The more a skill is practised, the more it is stored as a motor program in long-term memory, freeing working memory for tactics.

Reaction, movement and response time

• Reaction time is the time from the stimulus appearing to the start of the response.
• Movement time is the time from starting to completing the movement.
• Response time is reaction time plus movement time.

Factors that influence response speed

• Number of choices: more options slow reaction time.
• Predictability of the stimulus: an expected stimulus is responded to faster.
• Experience and anticipation: experts read cues early and anticipate, effectively reducing reaction time.
• Arousal: an optimal level sharpens attention; too much narrows attention and slows decisions.
• The psychological refractory period: a second stimulus arriving while the first is still being processed is delayed, which is the basis of a fake or dummy.