Final answer:
During arousal state transitions, there are several changes that can occur both prior to sleep onset and following arousal. These changes include shifts in brain wave activity and changes in muscle tension and body temperature. These transitions are part of the normal sleep cycle.
Step-by-step explanation:
During arousal state transitions, both prior to sleep onset and following arousal, several changes can occur. Prior to sleep onset, the brain transitions from being awake to falling asleep, characterized by a shift from alpha waves to theta waves. Following arousal, there can be an increase in overall muscle tension and core body temperature, as well as changes in brain wave activity. These changes in arousal state transitions are a normal part of the sleep cycle.