brainstem the hindbrain. The old mammalian brain roughly corresponds to the limbic
system that includes the septum, hippocampus, amygdala, cingulate cortex, hypothalamus;
the thalamus, which are all important in controlling emotional behavior, some aspects of
memory, and vision. The new mammalian brain or neocortex, synonymous with the cere-
bral cortex, accounts for about 80% of brain volume and is associated with the higher func-
tions of judgment, decision making, abstract thought, foresight, hindsight and insight,
language and computing, as well as sensation and perception. Developmental psychologists
call the structures of the “mammalian brains” the forebrain. The surface of your cortex has
peaks called gyriand valleys called sulci, which form convolutionsthat increase the sur-
face area of your cortex. Deeper valleys are called fissures. The last evolutionary develop-
ment of the brain is the localization of functions on different sides of your brain.
Localization and Lateralization of the Brain’s Function
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 func-
tions. This localization of structure and function has been identified for numerous regions
(see Figure 7.1). Association areasare regions of the cerebral cortex that do not have spe-
cific sensory or motor functions, but are involved in higher mental functions, such as
thinking, planning, remembering, and communicating. In general, 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.
68 ❯ STEP 4. Review the Knowledge You Need to Score High
Corpus callosum
Thalamus
Pituitary gland Hypothalamus
Hippocampus
Pons
Medulla
Reticular formation
Brainstem
Cerebellum
Amygdala
Cerebrum
Figure 7.1 Major structures of the brain in medial view.