Brain measuring time

Brain:

“How long the film that you just saw lasted?”

Maybe you can give such answers as “about two hours” easily, but have you ever thought how brain works when you answering the question? That is, how brain measures time? We do not know the answer but we are getting to know.

Brain measures time imprecisely – an experiment tells.

Nichols, a famous expert in neuroscience, once told me, brain could measure time precisely. I did not take it for grant and conducted an informal experiment myself. I chose three persons as my experimental objects in July, 1998 and took the real time during which they felt the time is 5 seconds (or 10, 20 seconds). The following is the data:

Time: 1998.07.17; 3:20pm

Name: Li Weimin, male, born on 1977.05.10

Emotion: excited

Time felt	Real time	Time felt	Real time	Time felt	Real time
5s	5.40	10s	9.44	20s	20.00
	4.25		9.41		19.34
	4.72		8.40		20.50
	4.87		9.06		18.41
	4.47		10.03		20.10
	4.10		10.63		15.82
	5.00		10.81		17.81
	4.13		11.06		18.47
	4.50		9.78		21.13
	5.00		8.50		20.03
average	4.64		9.71		19.16
difference	-0.36		-0.29		-0.84

Time: 1998.07.18; 9:20pm

Name: Ni Ting, male, born on 1977.12.21

Emotion: quiet

Time felt	Real time		Time felt		Real time	Time felt	Real time
5s	5.22	10s		9.44		20s	20.09
	4.53			9.03			21.91
	4.59			9.81			22.09
	5.00			10.78			22.75
	4.65			11.69			22.38
	5.16			11.00			20.94
	5.41			11.50			19.65
	5.34			12.59			21.75
	5.78			11.16			20.56
	4.91			11.81			20.34
average	5.06			10.88			21.25
difference	+0.06			+0.88			+1.25

Time: 1998.07.20;12:27am

Name: Shen Yufeng, male, born on 1978.11.17

Emotion: quiet

Time felt	Real time	Time felt	Real time	Time felt	Real time
5s	4.65	10s	11.22	20s
	4.22		9.25
	5.66		9.12
	5.75		8.12
	4.88		13.06
	6.09		8.94
	5.37
	5.94
	4.62
	4.97
average	5.22		9.95
difference	+0.22		-0.05

The data show that brain cannot measure time precisely. In some cases (for example in data 1), it is far from precise. Of course the data are difficult for analysis because they are insufficient. However, we also can see that one’s emotion affects the time measuring very much. (See data 1).

Brain’s measuring is far from imprecise – an experience tells.

Maybe you have such an experience:

You keep busy at dealing with documents and feel very tired. Then you get a chance to nap for a few minutes. Yes, you begin to nap and in the dream you find you are also dealing with the documents. You do and do and finally you finish. It much has taken you one hour! Suddenly you come to awake and find the real time is just five minutes!

One possible explanation.

One possible explanation is that there is a life clock (attention! different from life clock we commonly use, maybe it is a recycle of electrons) and brain use it to measure time. The clock’s elemental time period is determined by experiences. However, such a clock is generally imprecisely, especially when one is excited or sleeping.

However, deeper thinking shows there is no such a clock at all. Brain measures time just by the stored experiences. Of course brain has memorized many things and the time to finish them. It can compare some similar experience and then tell the time. But, especially when one is sleeping, experiences in dream are represented much faster than when one is awake and cannot be synchronized by real time.

Such an explanation is superficial and need support from experiments. However, we can expect the experiments are difficult to conduct because the designing of the experiments will meet another basic puzzle: how information saved in brain and how it represented?

This leads a basic problem: how information saved in brain and how it represented?