Localization and Lateralization of the Brain’s Function
6 Biological Bases of Behavior
STEP 4 Review the Knowledge You Need to Score High
Although multiple representations of information can be located within different areas of your brain, specific regions of your brain seem most critical in handling particular functions. This localization of structure and function has been identified for numerous regions (see Figure 6.1). Association areas are regions of the cerebral cortex that do not have specific sensory or motor functions but are involved in higher mental functions, such as thinking, planning, remembering, and communicating. In general, the crossing over of nerves sending information from one side of your body to the other side of your brain results in contralaterality, control of one side of your body by the other side of your brain.
Figure 6.1 Major structures of the brain in medial view.
“To help remember that the hippocampus aides in the formation of new long-term memories, just remember that ’hippos are like elephants and elephants never forget.’ Hippos = hippocampus = memory formation.”
—Sarah B, AP student
Just as a map or globe can be divided into hemispheres and continents, your cerebral cortex can be divided into eight lobes, four in the left cerebral hemisphere and four in the right cerebral hemisphere (see Figure 6.2). Go to http://www.g2conline.org and click on 3-D Brain for a more detailed view of a three-dimensional brain model. You can download it as an app.
Figure 6.2 Regions of the left cerebral cortex in lateral view.
Although specific regions of the brain are associated with specific functions, if one region is damaged, the brain can reorganize to take over its function, which is called plasticity. In phantom limb syndrome, a somewhat unfortunate example of plasticity, reorganization of the somatosensory cortex leads to someone experiencing sensations where a missing limb used to be.