Finally, Part 3 describes recent memory studies using rodents and birds. The section is made up of 11 chapters and builds on techniques devised in the early 1990s, when it became possible to genetically modify small animals, especially rats and mice, to relate specific genes to animal behavior, including memory. The majority of the chapters in this section focus on rodents, and a number of brain regions and neurochemical projections are examined—the hippocampus, fornix, amygdala, orbitofrontal cortex, and neostriatum, as well as cholinergic neurons of the nucleus basalis, medial septum, and vertical limb of the diagonal band and cholinergic projections to the cortex from the basal forebrain. Several memory systems are also explored. The last chapter describes studies of episodic-like memory in birds that use a food-caching paradigm test to examine memory for what, when, and where.