Are you " a lark" or "a night owl " ?

There is " a time keeper " in our brains ! Did you know that ? Where is "the stopwatch" in our brains believed to reside ? Have you noticed that the desynchronization between external and internal time can cause us a series of uncomfortable symptons ? There is even an expression in English to refer to these symptons : Jet lag. Check its meaning clicking on the link below ,ok ?

http://www.macmillandictionary.com/dictionary/british/jet-lag

Well,a cave explorer named Michel Siffre had a pioneering experiment in 1962.Then he could find out lots of important information about people's sleep cycles which you can watch and listen to them below.

Marco A.Sotomayor created this TedEd video that is narrated by Addison Anderson with Music by Adam Harendorf and Animation by TOGETHER www.wearetogether.ca.

You are going to see ,among other important things,that " Life in a lonely dark cave had warped Siffre's own perception of time despite his brain's best effort to keep him on track." 

 http://www.macmillandictionary.com/dictionary/british/warp_1

Well,I hope you may have enjoyed to know about this experiment .Have you written down any pieces of  interesting information to comment on them at the bottom of this post ? I hope so !

Last but not least, Scientists usually split people into two categories : "larks" or early risers and "night owls". They are totally different groups .The former rise near dawn,are most productive early in the morning,and go to bed early,while the ones  who fall in the second category are most productive late at night,go to sleep late,and also wake up late.The category where we belong is determined in part by our genes.

https://www.fastcodesign.com/3046391/morning-people-vs-night-people-9-insights-backed-by-science