Thirty-one-year-old author Joshua Cohen writes jumpy, post-everything babble, the kind where one story’s down-and-out drug dealer ponders the future of campaign finance reform. Whether that sends you into shivers or makes you smile is fairly predictive of how you might like Four New Messages, Cohen’s latest collection of stories, out this month from Graywolf Press. Cohen’s style is sometimes self-consciously literary (the protagonist of one story is the “type who’d give you a cig but not a light”), and just as often breaks out into nerdy, Pynchon-esque screeds (a story called “McDonald’s” delves into a tract on branding-induced neuroses). Exhausting if they weren’t so clever, Cohen’s comically dense ruminations don’t so much come to a boil as spill over with tales of pornography, hyperviolent video games, consumerism, and depression. The messages in Four New Messages are slightly sinister, sometimes cynical, but certainly not restrained.