Cognitive processes define the ways in which people take in,
store, transform, and manipulate information.
Although it is evident that these internal mental processes take place,
researchers continue to seek the exact location that make up cognitive functioning. In ancient times, cognition was thought to
dwell in the heart, but science has shown that cognition is a function of the
brain. Ethically, the only human brains
that can be used to study cognitive functioning are those that have sustain
damage through injury or illness. One of
the most famous cases of brain damage was Phineas Gage, who in 1848 survived an
explosion that sent a tamping iron through his left cheek bone and out the top
of his head (Macmillian & Macmillian, 1999). His story provided extensive research
opportunities for doctors to study the role the brain plays in cognitive
function and how the different areas of the brain support cognitive function.
The Role of the Brain
in Cognitive Functions
Gage lost a major part of his left frontal lobe when the
tamping iron pierced his head. Even with
the extensive damage to Gage’s brain he was still able to maintain motor
function and speech, as-well-as recall the incident (Macmillian &
Macmillian, 1999). It was not, however,
until his physical recovery that people began to take note of the changes in
his personality. John Harlow, the
physician that worked with Gage noted that he (once a hardworking, sensible
man) became surly, aggressive, and profane; thus, suggesting that cognitive and
behavioral changes take place within the frontal lobe (Damasio, Grabowski,
Frank, Galaburda, & Damasio, 1994).
This was further confirmed when surgeons (e.g., Starr and McBurney) began
noticing mental changes in patients with frontal lobe lesions. Later, modified surgical procedures removing
only tumorous tissues produced little to no behavioral abnormalities. Gage’s
case encouraged further neurological research about the theory of localization
of brain function and assisted in defining the different areas of the brain
that stimulate the different cognitive functions.
How Brain Areas
Support Cognitive Function
Since Gage’s incident, continued brain research has
identified four primary regions that support cognitive functioning: “the
occipital, temporal, parietal, and frontal lobes” (Stevens, 2010, para.
1). Just how these four primary regions
support cognitive function varies with each lobe. The occipital lobe supports visual
processing, encoding, and information relay.
The temporal lobe processes recognition (face and place), recall, and
storage (memory), as well as language comprehension and sound processing. Although the parietal lobe assists in visual
information, its primary responsibility is that of spatial processing,
sensation, and perception integration.
The frontal lobe, as seen in Gage’s case, supports rational decision
making (personal and social), the processing of emotion, and personality
(Damasio, et. al., 1994).
In the two decades of Gage’s incident, recovery, and the
manner in which he lived his life came a turning point for neurological
researchers. Gage was a living,
breathing person with sustainable brain damage, his story stimulated additional
studies regarding the localization of cognitive brain function. As additional cases of brain lesions emerged,
surgeon’s uncovered primary cognitive regions within the brain, supporting the
theory that cognitive functions are localized to the brain. Frontal, occipital, temporal, and parietal
lobes each support different cognitive functions. While this is true that each lobe may support
different cognitive functions, together they produce the functioning human mind.
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