Final answer:
Arthur's sleeplessness is likely caused by a disruption in his circadian rhythm due to traveling across multiple time zones, leading to jet lag. This condition affects his sleep-wake cycle, as it takes time for his body to adjust to the new environmental light-dark cycle.
Step-by-step explanation:
Arthur's restlessness and inability to sleep after flying from California to New York is most likely due to a disruption of his circadian rhythm. The circadian rhythm is a biological rhythm that occurs over approximately 24 hours, aligning with the external light-dark cycle and influencing sleep patterns. Traveling across time zones disrupts this natural rhythm, as the internal clock must re-synchronize with the new environmental cues, causing symptoms commonly referred to as jet lag, which include insomnia, fatigue, and irritability.
Jet lag significantly affects our sleep-wake cycle regulated by melatonin, a hormone that responds to the light-dark cycle. The synthesis of melatonin takes time to adjust to the new light exposure in a different time zone. To reduce the impact of jet lag and realign the circadian rhythm with the new environment, bright light therapy and the strategic use of melatonin supplements are often recommended.