Group entitativity refers to the degree to which people perceive themselves to be a unified team. the greater the level of entitativity, the more that people feel the group fills their needs, the more identification people have with their group, and the more:

I believe the answer is Group entitativity 
Group entitavity happen only if all members of that group had eliminated all of their individualistic purposes and live solely to serve the group's goal.
One example of a group entitativity would be the Japanese airforce soldiers during world war II, who were glad to conduct 'Kamikaze' (sacrificing their life by colliding their own planes to enemy's  base)

Apart of the parietal lobe