When skiing, we tend to quickly respond to a stimulus with a single response. When more than one stimulus is presented, our reaction time takes longer. The psychological refractory period is a delay of the response time to a second stimulus as a consequence of our brain still processing the first one when both stimuli are presented in quick succession. An example of this might be when we dangerously approach an object and another skier or snowboarder appears, our first reaction is turning to avoid the object, but simultaneously try to stop to elude a collision with the other skier/snowboarder. In this case, the second execution will be less effective because our brain has a limited capacity and both reaction responses overlap.
Skiers with lower reaction skills due to a limitation in their speed information processing will exhibit this feature more markedly than quicker reactive skiers, limiting their decision to one at a time. If we are descending on a slope and another person cuts off in front of us, and at the avoiding moment we perceive the sound of a second person approaching from behind, then our motor response to avoid the person crossing will be longer. In this situation, we have to decide to avoid the person cutting off by deviating from his path or by stopping so, at having two options, our decision time delays our reaction time.
Reaction time and motion speed of others
It is difficult to calculate the speed of other people on the slope if at the same time we move because our visual system must separate on the retina the image of the other persons’ motion from our image of our own motion. Also, there is to consider that it is easier to estimate someone’s speed moving laterally that if it does lengthwise facing us.
Reaction time and the number of stimuli and responses
Based on the proposal of the Dutch scientist Franciscus Donders, currently it is recognized the following classification:
- Simple reaction time occurs when we perform a single response to just one stimulus.
- Choice reaction time occurs when existing several stimuli, we have a response for each one of them.
- Recognition reaction time is when various stimuli appear and each one is associated with several possible responses but only some should be responded. The Hicks’ law would apply here, which postulates that the more response options, the more reaction time increases.
Reaction phases and types
Reacting to a stimulus could be divided into three phases:
- In the perception phase we assign sensory detection time of the stimulus by vision, hearing, or touch.
- The decision phase implies the time to determine the appropriate response.
- The execution phase is when we apply the chosen response.
Reaction types are:
- The reflex reaction, which is an instinctive reaction like blinking.
- The simple reaction needs a single response like stopping before a drop-off.
- The complex reaction is when we have to choose between several possible responses, taking longer decision and reaction time.
- The discriminating reaction is applied when we must choose between several responses that are not usual for us.
