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1.3: Connecting Biology to Behavior

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    Learning Objectives
    1. Discuss the Case of Phineas Gage and its contribution to biological psychology.


    While experiments are necessary to establish cause and effect relationships, in-depth studies of unique individuals or groups of people who share an experience can be used to inform our understanding of things that we can not study experimentally. Surgical errors, extreme mistreatment, and tragic accidents are impactful events that can alter individuals significantly, providing unique opportunities to study the effects of experiences which can not be ethically studied experimentally. There have been a number of these case studies which have revealed the role of different parts of the brain on our thinking and behavior. One such case is Phineas Gage. Gage lived 12 years after a rod pierced his skull, damaging his left frontal lobe. Researchers were able to gather information about his functioning before and observe his cognitive ability and personality after the accident. His case enabled the field to understand the role of frontal lobe in personality and mental processes.

    The Tale of Phineas Gage

    Phinease Cage after his accident, holding the rod that damaged his brain
    Figure \(\PageIndex{1}\): Phineas Gage Portrait After His Accident. (Public Domain; via Wikipedia Common)

    The case of Phineas Gage is worthy of expanded coverage as his tragic accident establishes a clear connection between the brain and who we are. Gage, a 25-year-old man, was employed in railroad construction at the time of the accident. As the company's most capable employee, with a well-balanced mind and a sense of leadership, he was directing a rock-splitting workgroup while preparing the bed of the Rutland and Burlington Railroad south of Cavendish, Vermont, USA. At 4:30 PM on September 13, 1848, he and his group were blasting a rock, and Gage was assigned to put gunpowder in a deep hole inside it.

    The moment he pressed the gunpowder into the hole with a bar, the friction caused sparks, and the powder exploded. The resulting blast projected the meter-long bar, which was 1.25 inches in diameter and weighed about 13.2 pounds, through his skull at high speed. The bar entered his left cheek, destroyed his eye, passed through the left front of his brain, and left his head at the top of the skull on the right side. Gage was thrown on his back and had some brief convulsions, but he woke up and spoke in a few minutes, walked with a little help, and sat in an ox cart for the 0.7-mile trip to where he was living.

    animation of where the rod was lodged
    Figure \(\PageIndex{2}\): The injury of Phineas Gage With Frontal Lobe shown in Red. (Public Domain; via Wikimedia Common)

    About 30 minutes after the accident, a doctor arrived to provide medical care. Gage had lost a lot of blood, and the next days that followed were quite difficult. The wound became infected, and Phineas was anemic and remained semi-comatose for more than two weeks. He also developed a fungal infection in the exposed brain that needed to be surgically removed. His condition slowly improved after doses of calomel and beaver oil. By mid-November he was already walking around the city.

    The Consequences

    For three weeks after the accident, the wound was treated by doctors. During this time, he was assisted by Dr. John Harlow, who covered the head wound and then reported the case in the Boston Medical Surgery Journal. In November 1849, invited by the professor of surgery at Harvard Medical School, Henry Jacob Bigelow, Harlow took Gage to Boston and introduced him to a meeting of the Boston Society for Medical Improvement .

    In his reports, Harlow described that the physical injury profoundly altered Gage's personality. Although his memory, cognition, and strength had not been altered, his once gentle personality slowly degraded. He became a man of bad and rude ways, disrespectful to colleagues, and unable to accept advice. His plans for the future were abandoned, and he acted without thinking about the consequences. And here was the main point of this curious story: Gage became irritable, irreverent, rude and profane, aspects that were not part of his way of being. His mind had changed radically. His transformation was so great that everyone said that “Gage is no longer himself.”

    As a result of this personality change, he was fired and could no longer hold a steady job. He became a circus attraction and even tried life in Chile, later returning to the United States. However, there is something still little known about Gage: his personality changes lasted for about four years, slowly reverting later. As a proof of this, he worked as a long-haul driver in Chile, a job that required considerable planning and focus skills. He died on May 21, 1861, 12 years after the accident, from an epileptic seizure that was almost certainly related to his brain injury.

    File:JacksonJBS A descriptive catalogue of the Warren Anatomical Museum 1870 frontispiece 623x1024.jpg
    Figure \(\PageIndex{3}\): Frontispiece, showing multiple views of the exhumed skull, and tamping iron, of brain injury survivor Phineas Gage (Public Domain; via Wikimedia Commons

    After his body was removed from its grave, Gage's mother donated his skull to Dr. Harlow who in turn donated it to Harvard University.

    The Legacy

    Gage's case is considered to be one of the first examples of scientific evidence indicating that damage to the frontal lobes may alter personality, emotions, and social interaction. Prior to this case, the frontal lobes were considered silent structures, without function and unrelated to human behavior. Scottish neurologist, David Ferrier, was motivated by this fact to investigate the role of frontal lobes in brain function. Ferrier removed the frontal lobes in monkeys and noted that there were no major physiological changes, but the character and behavior of the animals were altered. In other words, he confirmed the role of the frontal lobes that was suggested by Gage's accident in an experiment with a non-human animal.

    Knowledge that the frontal lobe was involved with emotions continued to be studied. The surgeon Burkhardt in 1894 performed a series of surgeries in which he selectively destroyed the frontal lobes of several patients in whom he sought to control psychotic symptoms, being the modern prototype of what was later known through Antonio Egas Moniz as psychosurgery. Today, it is well understood that the prefrontal cortex of the brain controls the organization of behavior, including emotions and inhibitions.

    Folkloric as it may be, but nonetheless remarkable, the contribution of Phineas Gage's case should not be overlooked, as it provided scientists the baseline for the promotion of studies in neuropsychiatry, and a source of inspiration for world medicine. In 2012, a team of neuroscientists used computer tomography of Gage's skull with typical brain MRI scans to simulate how extensive Gage's brain damage was. They confirmed that most of the damaged area was the left frontal lobe. However, surrounding areas and their neural network were also extensively severed. And it is not just the researchers who keep coming back to Gage. Medical and psychology students still learn about Gage from their history lessons. Neurosurgeons and neurologists still sometimes use Gage as a reference when evaluating certain cases. The final chapter of his life also offers us a thought-provoking discovery about cases of massive brain damage, indicating that rehabilitation may be possible.


    Phineas Gage made a huge contribution to our understanding of the frontal lobe damage and its subsequent change in personality. Furthermore, his case expanded knowledge in neurology in several areas, including the study of brain topography in behavioral disorders, the development of psychosurgery, and finally the study of brain rehabilitation. Also, Gage's case had a tremendous influence on early neuropsychiatry. The specific changes observed in his behavior pointed to theories about the localization of brain function and correlated with cognitive and behavioral sequelae, thereby acquainting us with the role of the frontal cortex in higher-order actions such as reasoning, behavior and social cognition. In those years, while neuropsychiatry was in its infancy, Gage's extraordinary story served as one of the first pillars of evidence that the frontal lobe is involved in personality, which helped solidify his remarkable legacy in world medical history.


    Adapted from Phineas Gage’s Great Legacy by Vieira Teles Filho, Ricardo. Licensed CC BY 4.0.

    This page titled 1.3: Connecting Biology to Behavior is shared under a CC BY license and was authored, remixed, and/or curated by Multiple Authors (ASCCC Open Educational Resources Initiative (OERI)) .