One of the threats facing social cohesion in highly exclusive societies is the potential for creating a widening gap between expectations and actual achievements, or for large discrepancies to develop between symbolic integration mechanisms (which increasingly operate through communications media) and the systemic means of material integration, which could turn into sentiments and conduits of frustration and aggression (ECLAC, 2007a; Hopenhayn, 2000, 2001). For approaches that highlight the role of cultural factors in the persistence of deprivation, low expectations of mobility and despair would be crucial expressions of social exclusion and poverty transmitted between generations (Atkinson, 1998; Narayan and others, 2000). For example, people might want quality education for their children (a normative expectation); but, at the same time, they might see this as unachievable (cognitive expectation) —either because of the multiple constraints they face in the opportunities structure.