George Galster, Wayne State University professor and co-author of a recent Brookings Institute study, commented about the decline of middle class neighborhoods in metropolitan areas. He said one reason for the decline is the type of housing being built, which restricts options for middle-class families. New subdivisions in the suburbs and high-end urban projects often aren\'t affordable for the middle class. The result is that the rich are even more likely to be surrounded by the rich, and the poor by the poor, with little movement between the two, Galster said. He also sees another effect: \"Can lower-income folks access the kinds of social networks and information networks that they could previously simply by rubbing shoulders with their neighbors? Answer: No,\" Galster said. \"So that says something about the potential for social mobility in the future.\"