why does yawning a contagiuos habit??

Philippines
July 28, 2008 3:50am CST
i come to realize that when a person next to me started to yawn,, a few seconds later i started to yawn also?? is this really a contagious thing? or just a psychological effect of thinking that when somebody yawns, its automatic that you will do it also unconsciously?
2 responses
@hellcowboy (7378)
• United States
29 Jul 08
I think that yawning is contagious and the reason it is,is because when you yawn it does not mean you are tired,it just means your brain is not getting enough oxygen,so I think when you see someone else yawn,it makes you yawn,so that way you will get more oxygen going to your brain,and that is why some people yawn a lot,and some people hardly ever yawn.
@dropofrain (1168)
• India
28 Jul 08
I think it is a contageous disease. AS and when you see some one yawning, even you start feeli9ng sleepy. I think it is psychological problem. Even the same is true for laughing. Once I see someone laughing, even I start laughing.