People actually live about 80 milliseconds in the past. That’s how long it takes the brain to assemble information that makes up consciousness. This is just an average time, though; some people have a shorter information assembly time than others. An easy way to experience this phenomenon is to touch two places on your body — for example, the top of your head and your knee — at the same time. Although the touches feel like they happen simultaneously, it actually takes longer for the signal from the knee to reach your brain than it takes the signal from your head. The brain compensates for the time gap in that 80-millisecond information assembly time.
More facts about time perception:
The way a person perceives time can be connected to his or her personality. People who tend to live in the present and don’t see the need for making detailed plans for the future are more likely to take risks or act impulsively, and people who think about the future a lot tend to be more focused and goal-oriented.
To the brain, remembering past events is very similar to imagining future events, which is why false memories can feel just as real as true ones.
Quantum physics research indicates that time might be a fundamental phenomenon of the universe, although it’s not entirely clear whether time is a fundamental force like electromagnetism or an emergent force like temperature.