Understanding Psychology (10th Ed)

 THE SENSORY AREA OF THE CORTEX 
Given the one-to-one correspondence between the motor area and body location, it 
is not surprising to fi nd a similar relationship between specifi c portions of the cortex 
and the senses. The
 sensory area 
of the cortex includes three regions: one that cor-
responds primarily to body sensations (including touch and pressure), one relating 
to sight, and a third relating to sound. For instance, the somatosensory area in the 
parietal lobe encompasses specifi c locations associated with the ability to perceive 
touch and pressure in a particular area of the body. As with the motor area, the 
motor area
The part of the cortex that 
is largely responsible for the body’s 
voluntary movement.
sensory area
The site in the brain of 
the tissue that corresponds to each of 
the senses, with the degree of 
sensitivity related to the amount of 
tissue.
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Module 9 
The Brain 
87
amount of brain tissue related to a particular location on the 
body determines the degree of sensitivity of that location: The 
greater the area devoted to a specifi c area of the body within 
the cortex, the more sensitive is that area of the body. As you 
can see from the weird-looking individual in Figure 6, parts 
such as the fi ngers are related to a larger portion of the somato-
sensory area and are the most sensitive.
 
The senses of sound and sight are also represented in spe-
cifi c areas of the cerebral cortex. An auditory area located in the 
temporal lobe is responsible for the sense of hearing. If the 
auditory area is stimulated electrically, a person will hear 
sounds such as clicks or hums. It also appears that particular 
locations within the auditory area respond to specifi c pitches 
(Hudspeth, 2000; Brown & Martinez, 2007; Hyde, Peretz, & 
Zatorre, 2008; Bizley et al., 2009). 
The visual area in the cortex, located in the occipital lobe, 
responds in the same way to electrical stimulation. Stimulation 
by electrodes produces the experience of fl ashes of light or 
colors, suggesting that the raw sensory input of images from 
the eyes is received in this area of the brain and transformed 
into meaningful stimuli. The visual area provides another 
example of how areas of the brain are intimately related to specifi c areas of the body: 
Specifi c structures in the eye are related to a particular part of the cortex—with, as 
you might guess, more area of the brain given to the most sensitive portions of the 
retina (Wurtz & Kandel, 2000; Stenbacka & Vanni, 2007).