Because of the notoriety of the Gage, the 19th century American neurologist, M. Allan Starr, used the Gage case as evidence that a tumor, injury or other damage a specific part of the brain such as the frontal lobe could be related to particular symptoms. According to Starr, Gage had suffered no sensory impairment and had no physical symptoms. "Starr advocated using Gage's alleged personality change as a way of diagnosing frontal tumors" (Macmillan, 1996, Phineas Gage and brain surgery). Eventually, as modern neuroscience progressed, "it soon became clear that in only about half the cases of frontal tumor were there any 'mental symptoms' and only in a minority of those did the symptoms resemble Gage's...At about the same time, in the early 1920's, Walter Dandy, the American brain surgeon, developed a more radical method of removing tumors. He had found that about 60% of brain tumors could not be removed because they were not sufficiently differentiated from the tissue around them. Dandy's new method removed the lobe containing the tissue" (Macmillan, 1996, Phineas Gage and brain surgery). Thus the influence of the Gage case continued. The ability of Gage to survive "may have reinforced the belief that large areas of the brain could be removed with relative impunity. It seemed that the brain could be operated on without causing death or major impairment of psychological functions" (Macmillan, 1996, Phineas Gage and brain surgery). While advocates of psychosurgery into the 20th century did not always cite the Gage case, it had an undeniable subtle, influence upon acceptance of the practice.

It was the late 19th century scientist David Ferrier who perhaps defined what...

Ferrier performed experiments on monkey's antero-frontal lobes, and while the damage lacked "definite physiological results... notwithstanding..I could perceive a very decided alteration in the animal's character and behavior, while it is difficult to state in precise terms the nature of the change...while not actually deprived of intelligence, they had lost, to all appearance, the faculty of the attentive and intelligent observation" (the incredible case of Phineas Gage, 2006, Neurophilosophy). Damage to the cortex seemed to produce damage to the executive function in the brain, thus regardless of Gage's exact injuries, his case provided and continues to provide clues as to what parts of the brain contribute to the ability of individuals to govern impulses, to focus, to plan, and to relate to the world in an attentive fashion.
Works Cited

The incredible case of Phineas Gage. (2006). Neurophilosophy.

Retrieved March 6, 2009 at http://neurophilosophy.wordpress.com/2006/12/04/the-incredible-case-of-phineas-gage/

Macmillan, M. (2006). Damage. Deakin University School of Psychology.

Retrieved March 6, 2009 at http://www.deakin.edu.au/hmnbs/psychology/gagepage/Pgdamage.php

Macmillan, M. (2000). Phineas Gage's Story. Deakin University School of Psychology. Retrieved March 6, 2009 at http://www.deakin.edu.au/hmnbs/psychology/gagepage/Pgstory.php

Macmillan, M. (1996). Phineas Gage and Brain Surgery.

Deakin University School of Psychology. Retrieved March 6, 2009 at http://www.deakin.edu.au/hmnbs/psychology/gagepage/PgSurger.php

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