Your brain is lying to you about time. Let's prove it.
When you cause something to happen, your brain compresses the perceived time between your action and its effect. Press the button and listen for the tone. Your brain will make you believe the tone happened sooner than it actually did.
Press the button when ready
This is called "intentional binding" - discovered by Haggard et al. in 2002. When you voluntarily cause an effect, your brain retroactively edits your perception of time, making the action and effect seem closer together. This binding effect is so reliable it's been proposed as a marker of agency and free will. Your brain is literally rewriting history to make you feel more in control.
Two stimuli will flash. Which came first? Sounds simple, but your brain's timing circuitry is more fallible than you think. At small intervals, you'll experience genuine temporal reversal.
Your brain has a "temporal resolution" of about 30-50ms for visual stimuli. Below this threshold, the order of events becomes ambiguous and your brain essentially guesses - or worse, perceives them in the WRONG order. This is why eyewitness testimony about rapid events is notoriously unreliable. Your conscious experience of "now" is actually a ~100ms window where causality can flip.
A moving object and a flash occur at the exact same position. But you'll perceive the flash as lagging BEHIND the moving object. Your brain predicts motion and makes the present moment into a fiction.
This is the "flash-lag effect" - your visual system extrapolates the position of moving objects into the future to compensate for neural processing delays. When a flash occurs, it has no motion to extrapolate, so it appears to lag behind. You're literally seeing the moving object where it WILL be, not where it IS. Your perception of "now" is actually a prediction of the near future.