Modern society's increasing dependency on online tools for both work 
and recreation opens up unique opportunities for the study of social 
interactions. A large survey of online exchanges or conversations on 
Twitter, collected across six months involving 1:7 million 
individuals is presented here. We test the theoretical cognitive 
limit on the number of stable social relationships known as Dunbar's 
number. We and that users can entertain a maximum of 100  200 stable 
relationships in support for Dunbar's prediction. The \economy of 
attention" is limited in the online world by cognitive and biological 
constraints as predicted by Dunbar's theory. Inspired by this 
empirical evidence we propose a simple dynamical mechanism, based on 
fnite priority queuing and time
resources, that reproduces the observed social behavior.

http://arxiv.org/PS_cache/arxiv/pdf/1105/1105.5170v1.pdf


"People Who experience mood swings, fear, voices and visions"