Yeah it could be that cause and effect are distinct events that are both part of a larger event. My intuition is that there’s something special about causation underlying causal binding.

Also note that in E2, the non-event condition involved intervals filled with sounds, whereas the event condition involved intervals that were silent except for the test tones.

Interesting question! A key difference is that our subjects judged the duration between tones, not the duration of the whole interval. The period between tones is not itself filled with tones so it’s not clear how the filled interval illusion can explain our effect.

Interesting comparison! My understanding of intentional/causal binding is that it’s not due to events per se, but due to a representation of (intentional) causation. The intentional action and its consequence may not both be within an event the same way the tones are in our study.