Final answer:
The study by Gilovich et al. (2000) explored the concept of the spotlight effect.
Step-by-step explanation:
The study by Gilovich et al. (2000) explored the concept of the spotlight effect. The researchers found that participants wearing T-shirts with singer Barry Manilow overestimated how much other people would notice the T-shirt. This demonstrates that people tend to think they are being noticed and observed more than they actually are.