In 1950 Karl Lashley published his influential manuscript In Search of the Engram, in which he concluded that memory was widely distributed in the mammalian brain and that there is no apparent localization of mnemonic traces within specific brain structures. Five decades' worth of research since then suggests that his conclusion may have been partially incorrect. Whereas it is clear that distributed brain structures do indeed participate in mnemonic functions, it is also the case that there is some degree of neuroanatomical localization of learning and memory. There is extensive evidence that memory is organized in multiple systems that differ in terms of the type of memory they mediate. The multiple-memory-systems hypothesis is supported by findings of neuroscientific research in several mammalian species, including rats, monkeys, and humans (Hirsh, 1974; O'Keefe and Nadel, 1978; Olton, Becker and Handelmann, 1979; Packard, Hirsh, and White, 1989; Kesner, Bolland, and Dakis, 1993; Mishkin and Petri...