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After a biological clock, which controls our time experience in a second or minute range, brain researchers have been searching for a long time. New insights show, that our physical feeling plays a central role: Self-Perception and time experience are inseparably connected to each other.

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How does our feeling for time emerge - Part 1

The lid of the floating tank is closing over me, I am lying weightlessly in the body-warm salt water. It is pitch-black and no noise is getting through to me from the outside. My senses, which normally serve for orientation in the environment, don't receive any signals. My physical boundaries become blurred. I am not totally by myself and my thoughts. Only one sense is present, the body sense. I feel myself with my physicality - breathing, the muscles of my extremities, which are floating in the water in a relaxed way. Something else is coming more and more into foreground: I can clearly sense, how time is slowly passing, second after second.

The American doctor John C. Lilly developed an isolating container to explore consciousness under longer lasting sensory deprivation at the National Institute of Mental Heal in the year 1950. Today, this floating tank is used in short treatments for deep relaxation. What has to be learned over years through meditation, namely to not let yourself be distracted from outer sensory stimuli, can be experienced within minutes. Only the thoughts remain, that have to be calmed down.

Soon scientists realized, that sensory deprivation is suitable for capturing perception of time. They differentiated two essential aspects: On one side, the current experience of time and on the other side its progression in retrospection. If we watch out for time, sometimes it seems to pass in a flash (f.e. when we are having an exciting conversation with somebody). In other cases, time seems to flow very slowly (f.e. when we are waiting for the train to come).

But we also make judgment about periods of time, that happened in the past, f.e. when we notice, that the last year was passing by very fast again. This is easy to explain: Afterwards the amount of diverse experiences which are recalled from memory for the specific duration, characterize subjectively perceived duration. The more you experience and are able to remember it, the longer someone perceives time to be lasting. A varied and eventful holiday seems to be longer as the same duration in the monotony of everyday life. That's why our live seems to pass on faster and faster, because we - compared to our childhood, youth and early adult age - as getting older goes on, experience less and less new things, while the routine increases more and more.

Perception of time in an experiment

In an experiment about perception of time the experimental subjects had to listen to a tone of a specific length. While listening to the tone the activity in the back of the insular lobe (yellow) increased continuously til the end of the marked interval of the tone. This brain region representing ongoing physical states can mirror body signals and therefor be used as timer.


While the retrospective time experience can be explained quite well, perception of time still puzzles scientists. How does the feeling about duration emerge, although we don't have a sense for it.

That's why brain scientists have searched for a biological clock in the brain, which would make time assessment in the second and minute range possible. They developed a lot of concurrent neuronal models and located the different areas of the brain: in the basal ganglia, in the cerebellum or in the right side of the frontal lobe, to name just a few. This regions are actually involved in time experience, because they fundamentally contribute in the neuronal functions like attention and working memory, but also motivity. Eventually I constantly care (more or less) about time, memorizing the duration of a specific interval, reacting in the right point of time with a gesture. The prove about a genuine biological clock, which encodes duration, hasn't been found yet. So the question, how subjective perception of time duration emerges, stays.

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Perception of Time: How does our feeling for time emerge - Part 2