Figure 1. Sound localization by barn owls. The barn owl can accurately localize sounds even in complete darkness. A sound-based representation is found in the external nucleus of the inferior colliculus. There, cells are tuned to sounds that occur in particular locations in space, as depicted by the rectangles shown in front of the owl. The cells are arranged in the external nucleus according to their tuning.

Figure 2. Anatomy of Aplysia. When the mantle shelf is touched, the gill reflexively withdraws. This reflex is modified by different forms of learning, which entail changes in the synapses between the sensory neurons (SN) receiving the touch to the mantle shelf and the motor neurons (MN) that produce the gill withdrawal.

Figure 3. Locust flight is an example of a rhythmic behaviour that is controlled by a central pattern generator.

Figure 4. The extremely sensitive touch organ of a star-nosed mole. A photograph shows that the star consists of 11 appendages surrounding each nostril; these are numbered on one side. The right panel shows a preparation of brain tissue from the cortex of the mole that has been stained for cytochrome oxidase; this reveals a star pattern within the brain. The neurons are segregated according to their sensitivity to touch stimuli delivered to the different appendages; for example, the cells responding when the 1st appendage is touched all lie in the area marked 1, the cells responding when the 2nd appendage is touched lie in the area marked 2, and so on. Note that the 11th appendage takes the most space.

Figure 5. Vocal learning in songbirds. Song learning has been documented in many songbird species, including various sparrows, zebra finches and canaries. The diagram shows the song system, which is a set of specialized brain regions found uniquely in birds that learn to sing. These brain areas contain the neural substrates for song learning and production.