Who has never felt time go by faster? According to scientists, the explanation for this sensation may lie in our neurons and in the time of exposure to certain stimuli.
When we receive a visual or auditory stimulus of the same duration over and over again, neurons in a certain part of our brain begin to become exhausted and decrease activity. For example, when we watched the same movie or we hear the same song over and over.
Consequently, we can perceive time passing in a slightly distorted way. Both for more and for less.
According to a study published in the scientific journal Journal of Neuroscience, the tiredness of a group of neurons especially sensitive to the notion of time – located in the supra marginal gyrus, part of the brain responsible for sensory processing – may be the cause of this sensation.
Understand the study
To investigate the relationship between these neurons and the perception of time, the scientists selected a group of 20 people, with an average age of 21 years.
In the first phase of the research, they show participants the same image (a gray circle) for very short periods of time, less than a second, 30 times in a row.
Part of the group received the short version of the stimulus, 0.25 seconds, and another part, the long version, 0.75 seconds.
Then the scientists started testing to see if their perception of time had changed. The researchers showed participants the same circle for slightly longer periods of time: 0.35; 0.45; 0.55 and 0.65 seconds each. At the same time, a sound tone lasting 0.50 seconds was played.
Subsequently, participants were asked to indicate whether the noise had lasted more or less than the display of the images. For those who received the short repetitions in the first phase of the study, the noise that lasted 0.5 seconds seemed to be faster than the image display on the screen that lasted 0.35 seconds.
On the other hand, for people who received the longest repetition, 0.75 seconds, the effect was the opposite. Participants felt that the noise took longer than images that stayed longer on the screen, such as 0.65 seconds.
Your neurons may be lying to you
During the tests, participants had their brains scanned by a functional MRI machine, capable of detecting activity in the organ. At this stage, scientists realized that time-sensitive neurons had less activity. It was as if they were tired after the sensory repetitions to which they were submitted.
According to the study’s authors, this could explain why we feel time passes differently than time called physical.
“It is better not to trust your perception of time after being exposed to repeated flashes of images or noise,” says Masamichi Hayashi, a neuroscientist at Japan’s Osaka University.
Although the results may shed light on still mysterious aspects of the relationship between humans and time, there is a warning. Hayashi recalls that the research he conducted has the limitation of having investigated these changes in perception for very short periods of time.
“Future research will have to study whether our results can be applied to the perception of longer time intervals”, concludes the scientist.
EVERTON LOPES BATISTA / FOLHAPRESS