Understanding Psychology (10th Ed)

RETHINK
Brain scanning techniques allow people to communicate via brain waves alone.
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Module 9 
The Brain 
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Hidden within the forebrain, the
 thalamus 
acts primarily as a relay station for 
information about the senses. Messages from the eyes, ears, and skin travel to the 
thalamus to be communicated upward to higher parts of the brain. The thalamus 
also integrates information from higher parts of the brain, sorting it out so that it can 
be sent to the cerebellum and medulla.
The
 hypothalamus 
is located just below the thalamus. Although tiny—about the 
size of a fi ngertip—the hypothalamus plays an extremely important role. One of its 
major functions is to maintain homeostasis , a steady internal environment for the body. 
The hypothalamus helps provide a constant body temperature and monitors the 
amount of nutrients stored in the cells. A second major function is equally important: 
the hypothalamus produces and regulates behavior that is critical to the basic sur-
vival of the species, such as eating, self-protection, and sex.
The Limbic System: 
Beyond the Central Core
In an eerie view of the future, science fi ction writers have suggested that people 
someday will routinely have electrodes implanted in their brains. Those electrodes 
will permit them to receive tiny shocks that will produce the sensation of pleasure 
by stimulating certain centers of the brain. When they feel upset, people will simply 
activate their electrodes to achieve an immediate high. 
Although far-fetched—and ultimately improbable—such a futuristic fantasy is 
based on fact. The brain does have pleasure centers in several areas, including some 
in the