Question

In one study, zacks et al. (2009) recorded someone making a sandwich and asked participants to press a button when they thought one action was complete. the results of the study indicated that _______were indicative of the end of an action.

Answer 1

I believe the answer is: Changes in speed
Average people tend to become more focus and accelerate our effort when we're on the brink of finishing a certain goal.
So in the scenario above, when a sudden tense/increased movement happen in our body the researchers could perceive it as we're on the brink of finishing an action.