Limbic System: Brain system the size of a peach pit that exists deep in the center of our cerebral noggin, and regulates primary emotional and drive states (curiosity, hunger, thirst). To psychologists other than the neuropsychological sort, the limbic system is replaced by the 'limbo' system, a foggy metaphorical brain compartment that is physically neither here nor there, but is a lot easier to conceptualize (e.g. massive modularity, homunculus, free will), yet ends up doing the same thing even though it's a bogus and ad hoc fabrication.
