A new study provides evidence that our causal assumptions shape our perceptions of the temporal order in which we experience events occurring. The findings, which have been published in the journal Psychological Science, shed light on the influence of causality on time perception.
“Initially we became interested in backwards causation, and whether, under some circumstances, people can perceive causes happening after their effects, such as when praying or hoping for an outcome for something that has already occurred,” explained study author Christos Bechlivanidis, an associate professor at University College London.
“After running a few experiments, we quickly realized that the expectation of a temporal direction (that causes precede their effects) is so strong that even if we reverse the order, people insist to have seen the causes happening first. This made us interested in the nature of time perception and the way it interacts with causality (which also carries temporal information).”
In three experiments, which included 607 individuals in total, participants observed a domino-effect collision involving three colored squares, which were labeled “A,” “B,” and “C.”
In the expected ordered of collisions, A collides with B, which then collides with C. However, in the version that participants saw, “A moves first, but at the time of its making contact with B, C starts moving, and B starts moving only 150 ms later than that.” In other words, C starts moving before B collides with it.
In the experiments, the participants were asked to indicate the time at which B and C started moving. Despite repeated viewing of the collisions, the researchers found that participants tended to report that B had started moving before C, rather than the actual movement order (A, C, B).
“We have a strong assumption that we know, through direct perception, the order in which events happen around us. The order of events in the world is the order of our perceptions. The visual signal of the glass shattering follows the signal of the glass hitting the ground, and that is taken as irrefutable evidence that this is indeed how the events occurred,” Bechlivanidis told PsyPost.
“Our research points to the opposite direction, namely, that it is causal perceptions or expectations that tell us in what order things happen. If I believe that the impact is necessary for the glass to break, I perceive the shuttering after the impact, even if due to some crazy coincidence, the events followed a different order. In other words, it appears that, especially in short timescales, it is causation that tells us the time.”
The researchers emphasized that there is still much to learn about how assumptions about causality influence our perceptions.
“There are two main avenues for further work, in light of the causal reordering effect,” Bechlivanidis explained. “First, we need to investigate more generally the perception of temporal order. It might be the case, that, as the philosopher Rick Grush argues, when events happen fast, we never perceive but always deduce their order, based on our expectations and predictions.”
“Equally intriguing is the evidence of the effect for the study of causal perception, the idea that we perceive causes the same way as we perceive color or depth,” he continued. “In the reordering effect, one of the main cues used in causal perception, temporal precedence, is violated, but the sequence of events still appears causal to participants. This goes against a 60-year-old literature, and suggests that causal perception, or perhaps coincidence detection, is possibly much more ubiquitous and flexible that currently assumed.”
The study, “Human Vision Reconstructs Time to Satisfy Causal Constraints“, was authored by Christos Bechlivanidis, Marc J. Buehner, Emma C. Tecwyn, David A. Lagnado, Christoph Hoerl, and Teresa McCormack.