The primary motor cortex and somatosensory cortex are organized as maps that represent different body regions, as shown in Fig. 36.24. The neurons that control movements of the foot and lower limb are located near the mid-axis of the motor cortex. Those that control motions of the face, jaws, and lips map to the side and farther down in the primary motor cortex. There is a similar topographic map in the somatosensory cortex for pressure and touch sensation. Regions such as the fingers, hands, and face that are involved in fine motor movements and distinguishing fine sensations are represented by larger areas of the cortex.

The auditory cortex in the temporal lobe is similarly organized as a map. This region processes sound information transmitted from the cochlea of the ear. Neurons in the auditory cortex are organized by pitch: Neurons sensitive to low frequencies are located at one end and neurons sensitive to high frequencies at the other. With the evolution of language in humans, regions farther back in the temporal lobe developed into language and reading centers. These centers are linked by pathways to a specialized motor center controlling speech, located at the base of the primary motor cortex of the frontal lobe. Functions of the temporal lobe include object identification and naming. An individual with damage to the temporal lobe may lose the ability to recognize faces, even though he or she may still recognize others by voice or other body features.

The occipital lobe topographically maps visual information received from the optic nerves. The topographic mapping of information from retinal ganglion cells enables the brain to detect patterns and motion that are precisely related to different regions of the visual field. As a result, highly visual animals, such as humans, primates, and birds, are able to detect complex patterns and movements in their environment.