But you’ve packed and unpacked so many times you’ve lost track
“When a man sits with a pretty girl for an hour,” said Albert Einstein, “it seems like a minute. But let him sit on a hot stove for a minute, and it’s longer than any hour.” Einstein was describing one of the most profound implications of his Theory of General Relativity - that the perception of time is subjective. This is something we all know from experience: time flies when we are enjoying ourselves, but seems to drag on when we are doing something tedious.
The subjective experience of time can also be manipulated experimentally. Visual stimuli which appear to be approaching are perceived to be longer in duration than when viewed as static or moving away. Similarly, participants presented with a stream of otherwise identical stimuli, but including one oddball (or “deviant”) stimulus, tend to perceive the deviant stimulus as lasting longer than the others. The underlying neural mechanisms of this are unknown, but now the first neuroimaging study of this phenomenon implicates the involvement of brain structures which are thought to be required for cognitive control and subjective awareness.
The apparent prolonged duration of a looming or deviant stimulus is referred to as the time dilation illusion, and three possible, but not mutually exclusive, explanations for why it might occur have been put forward. First, the stimulus might be perceived as lasting longer because it has unusual properties which require an increased amount of attention to be devoted to it. Alternatively, the perceived duration of the stimulus might reflect the amount of energy expended in generating its neural representation (that is, duration is a function of coding efficiency). Finally, the effect might be due to the intrinsic dynamic properties of the stimulus, such that the brain estimates time based on the number of changes in an event.
