Final answer:
Visual-motor reaction time for unexpected events varies based on individual factors including experience and age. Muscle contraction speed is influenced by the central nervous system's response to conditions, affecting reaction times as well.
Step-by-step explanation:
The visual-motor reaction time for unexpected events varies based on individual factors, which can include a person's experience, age, and physical and mental health, among others. Experience can help to decrease reaction time, as the body and mind become more attuned to specific stimuli and better at anticipating and responding to similar situations in the future. However, as individuals age, certain senses and reaction times may slow down, although this is not uniform across all people and can be influenced by many factors.
Muscle contraction speed, which is a critical part of reaction time, can vary due to the responses of both the somatic and central nervous system to local conditions, which can either speed up or slow down this process. For example, signals that travel through the sensory pathway, within the central nervous system, and through the motor command pathway take only a fraction of a second under normal conditions.