Answer:
conflict.
Step-by-step explanation:
Tyler needed to rehearse for his competition, but the time he had to practice was the same as his friends had to go to parties. Tyler had an obligation to practice, but he also had a desire to have fun and party with friends. Sensation versus desire created a conflict in Tyler's mind that stirred his psychological. For this reason, we can consider that Tyler's psychological was very exhausted from the conflict and represented this exhaustion with a terrible stomach problem.
From this we can conclude that Tyler's disease may be related to conflict.