Time can seem to pass at different rates. As Albert Einstein once joked:
“Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute. That’s relativity.”
This is because the brain has no direct access to physical time and infers time from the neural representation of external events. Subjective time is believed to be “warped” by the neural energy involved in representing sensory inputs.
Its deviation from physical time has mostly been attributed to the sensory properties (e.g., size, luminance, speed, etc.) of external stimuli. But what role, if any, do we the experiencers play in our experience of time?
Psychologists Zhou Wen, Jiang Yi and their colleagues at the Institute of Psychology, Chinese Academy of Sciences, investigated these questions in a study where they showed volunteers pairs of movie clips, each featuring two human figures outlined by dots.
One of the two motion sequences was presented for 1000 ms, the other for 400 to 1600 ms. Participants were then asked to press one of two buttons to indicate which motion sequence was longer in duration.
Their duration judgments revealed a temporal compression effect (Experiment 1, Figure 2A): Motion sequences showing agents acting communicatively were perceived to be significantly shorter in duration in comparison with those acting noncommunicatively.
Psychometric functions and points of subjective equality (PSEs) for Experiments 1 (A), 2 (B), and 3(C). (Figure 2) Credit: Zhou Wen
The effect disappeared when the motion sequences were shown upside down, when a temporal lag was inserted in between the original upright acting agents (Experiment 2, Figure 2B), and when the two upright agents in each display were spatially swapped such that they faced in opposite directions (Experiment 3, Figure 2C).
In other words, the temporal compression effect was not due to the spatial-temporal correlation between the moves of the two agents. Could it be a manifestation of the observer’s social proficiency?
The researchers assessed participants’ social proficiency with the Autism Spectrum Quotient and found this to be the case: socially less proficient individuals were less susceptible to the effect than socially proficient ones (Experiment 4). Previous studies have shown that people who are more social tend to have higher levels of a hormone called oxytocin in their blood.
The researchers further showed that intranasal oxytocin administration promoted the temporal compression effect in socially less proficient individuals (Experiment 5). By contrast, in socially proficient individuals with overall higher levels of endogenous oxytocin, the very effect was diminished following the application of an oxytocin antagonist called atosiban (Experiment 6).
The perception of time thus varies between people and may depend at least in part on personality.
These results open up a new avenue for studying and manipulating how we process social situations. This could eventually benefit people who struggle with social interactions, such as those with autism spectrum disorders.
Funding for the work came from the National Natural Science Foundation of China and Chinese Academy of Sciences.