Something that Robert Provine has pointed out, as you can see here, and the reason why we were laughing when we heard those funny laughs at the start, and why I was laughing when I found my parents laughing, is that it's an enormously behaviorally contagious effect.
Nagu näete, ja sama leidis ka Robert Provine, on naermise põhjus selles, ja seda nii varasemates naeruklippides kui ka siis, kui ma oma vanemaid naersin, et naer on kohutavalt nakkav. Naer hakkab lihtsalt külge.