In the context of the double-slit interference experiment, what exactly does “observation” mean? Specifically, does the act of visual observation by intelligent creatures, such as humans, play a role in determining whether light behaves as a particle or a wave?

I’m trying to understand how the concept of observation impacts the behavior of light in this experiment. How is observation defined in the quantum mechanical sense, and what role does it play in the interference pattern observed on the screen? Does merely looking at the experiment change the outcome, or is there a more technical aspect to what “observation” entails in this scenario?

Any detailed explanations or references to relevant quantum mechanics principles would be greatly appreciated!