Phineas Gage, Gauging Time
Why do people feel the hours pass more slowly or quickly than they really do? The famous story of a man who lived after an iron flew through his skull holds clues.
On Wednesday, September 13, 1848, 25-year-old Phineas Gage was helping lay a railroad track through Cavendish, Vermont, for the Rutland and Burlington Railroad Company. It was 4:30 pm, and the sun was still out as he used a tamping iron to pack explosive powder into a long ditch. Without warning, the powder exploded and the iron—roughly 3.5 feet long, an inch wide, and 13 pounds in weight—flew from his hand and through his left cheek. It tore through his brain and the back of his skull, landing more than 80 feet away “smeared with blood and brains,” as his biographer Malcolm Macmillan would later write. Gage was immediately blinded in his left eye and fell to the ground. But he didn’t die. He convulsed on the ground then he got up, boarded an oxcart, and rode into town, less than a mile away.
The doctor Edward H. Williams received him in town. “I first noticed the wound upon the head before I alighted from my carriage, the pulsations of the brain being very distinct,” Williams wrote of meeting Gage. With a burned face, burned arms, and bits of his brain visible through his skull, Gage said, “Doctor, here is business enough for you.”
Williams invited Gage into a room in the hotel in Cavendish, where he examined the wound. Soon after, John Martyn Harlow attended to him as well. “Mr. Gage persisted in saying that the bar went through his head,” Williams wrote. “I did not believe Mr. Gage's statement at that time.” Gage stood up and vomited. As he vomited, “about half a teacupful of the brain” fell on the floor.
Williams removed bits of dirt that had gotten in Gage’s brain. He partially closed the wound so that it could still drain and applied a wet compress before bandaging his head. Gage spent the night alone. He told Williams, he did “not care to see his friends, as he shall be at work in a few days.”
Gage was too optimistic about his prognosis, but even though he wasn’t back to work in a few days, he was able to walk around within about two months. It was at this time that his friends started noticing a difference in his behavior.
He was “no longer Gage,” according to Harlow. His employers had once called him “a shrewd, smart businessman, very energetic and persistent in executing all his plans of operation.” Now he could not keep a schedule. Once a quiet, respectful man, he now engaged in “the grossest profanity,” and he showed “little deference for his fellows.”
Years later, his family and friends also began to notice his confusion with time, according to Macmillan’s account. He claimed that minutes would drag or speed up without warning. “Given what we know about frontal-lobe injuries,” says John Darrell Van Horn, an associate professor of neuroimaging and informatics at the University of Southern California, it follows that Gage could have “had problems with perseveration and with time distortion.”
Gage wanted to return to work for the railroad company but they didn’t want him back, deeming him mentally unfit. For a few months he took a job at Barnum’s American Museum in Manhattan, where he stood in a corner and held a tamping iron for museumgoers to ogle. He soon grew tired of the freak show and found a job in New Hampshire where he worked as a horse groom and carriage driver at the Hanover Inn. He was fired for “mental unsuitability” and took a similar job in Chile.
In January 1860, he moved to Santa Clara, California, so he could be near his mother. A month later he started having the most serious epileptic seizures he had experienced since the accident. At 5 a.m. on May 20, 1860, Gage fell into a series of long seizures, losing control of his body for minutes at a time. The seizures continued throughout the day and the night. The next morning, at age 36, 11 and a half years after the accident, the flying iron finally killed him.
* * *
In 2012, more than 150 years later, Van Horn looked at a digital model of Gage’s skull on his computer. Van Horn had long been interested in Gage, a man whose condition has piqued the curiosity of many in the fields of psychology and neuroscience. But besides a few diaries and two official medical reports, relatively little is known of Gage.
One of the most useful pieces of evidence in his case was a series of computerized tomography (CT) scans taken in the early 1990s. “These were the last known, best-quality images of Gage’s skull,” Van Horn told me. No autopsy was performed on Gage after his death, but due to Harlow’s persistence in 1866, five years after he died, Gage’s body was exhumed and his skull removed. Gage’s skull has been housed at the Warren Anatomical Museum at Harvard University for the past century, and Harvard’s archivists unearthed the CT scans for Van Horn.
Using the CT scans and Harlow’s reports, Van Horn and his team set out to digitally recreate Gage’s skull. If they could create a digital replica of Gage’s skull and the lesion in his brain, they could model the flight of the tamping iron and see exactly which part of his brain it had penetrated.
After modeling more than 1 million different possible entry-points for the tamping iron and all of the specific injuries that each entry point would imply, Van Horn’s mathematical model showed him exactly where the tamping iron penetrated Gage’s brain. He saw that Harlow’s initial autopsy was essentially correct: The iron had mostly affected Gage’s frontal lobe. What Harlow did not know—and what Van Horn discovered—is that it was specifically the left frontal lobe and the orbitofrontal cortex that were damaged by the iron. The orbitofrontal cortex is most associated with socially inappropriate behavior, emotional changes, and a loss of inhibition, all of which were symptoms reported repeatedly by Gage’s friends and family. “Gage clearly had behavioral changes due to brain injury,” Van Horn says.
150 years after Gage’s death, Van Horn became the first to provide an extensive neurological explanation for the reported behavioral changes in perhaps the most famous neurological patient in history. What Van Horn could not find, however, was an explanation for Gage’s peculiar perception of time.
* * *
About a decade earlier, on a spring morning in 2003, Heather Berlin left her dorm room beneath the spires of Magdalen College in Oxford, England, where she was a doctoral student, and made her way to her office in the department of experimental psychology up the road.
At the New School in New York, where Berlin completed her master’s degree, she conducted a study of time perception by having participants read index cards with random numbers printed on them, then asking the participants how long they thought the task had lasted. Reading the numbers out loud kept participants from counting to keep track of time.
“I literally just flipped these cards and had them read these random numbers,” Berlin told me. “I would sit there with my stopwatch and was timing it and it was all very manual.” At Oxford she asked a fellow doctoral student skilled in computer programming to digitalize her research method, allowing her to carry the test around on her tablet computer.
With her iPad in tow, Berlin spoke to healthy people and people with orbitofrontal cortex lesions in Oxford and London and subjected them all to her digitized time-perception test. Berlin asked participants to tell her when they believed 90 seconds had passed as she distracted them with the randomized numbers. Participants with undamaged brains tended to let a few more than 90 seconds pass before stopping her, indicating a slightly slower perception of time. Participants with orbitofrontal cortex damage, however, would stop her at almost exactly 90 seconds, indicating a more accurate perception of time.
But being accurate isn’t necessarily a good thing. An accurate perception of time can be evolutionarily disadvantageous. One reason why people with healthy brains might perceive time as slightly slower than it actually is (and therefore wait until 95 or 100 seconds have passed before saying 90 seconds have passed) may come down to a neurotransmitter called neuropeptide-Y (NPY).
Charles A. Morgan at the Yale School of Medicine conducted a study four years before Berlin’s findings, where he tested the amount of NPY present in the brains of U.S. Army soldiers. He assessed soldiers prior to training to establish a “control” group, then tested soldiers after a high-pressure, 24-hour survival training, or after what he termed a “P.O.W. experience,” in which soldiers were interrogated, for training, in a tense, realistic prisoner of war situation. This gave him “stressed” group to work with.
When people with normal brains are stressed, adrenaline is released. The brain is readying the person to attack or to run, according to David Eagleman’sresearch at Baylor College of Medicine’s Laboratory for Perception and Action. If the situation is sufficiently stressful, then the responses of alarm and fear could become so intense that, without the counteracting release of NPY, they would debilitate the prefrontal cortex, which affects rationality and decision-making, according to Morgan. Fortunately, the release of NPY helps to regulate stress, Morgan says. He found that soldiers who had just undergone survival training or the mock interrogation—the “stressful” group—had significantly greater levels of NPY compared to his control group of soldiers who had not been submitted to these situations. He added that it is not military training that produces these NPY differences but that anyone put in a stressful situation would show higher levels of NPY. Without NPY it would be extremely difficult for people to maintain cognitive skills, motor skills, and decision-making abilities when faced with danger.
As Berlin’s experiment showed, people with healthy brains experience time slightly slower than it is actually is not just in dangerous situations but in normal situations as well. The potential reason for this, according to Morgan’s research, is that NPY is always being released, just at lower levels during safe situations. So for healthy people, time always seems a little slow, with the potential to slow down even more in the face of danger. This function of stress regulation in the brains of healthy people means that they are able to remain calmer and act more reasonably, in danger and the rest of the time, Morgan says.
People with orbitofrontal cortex damage, however, have a more accurate (which, relative to healthy people, is a faster) perception of time. Berlin told me that this tends to make people with orbitofrontal cortex damage “feel pressured to react more quickly when it might be more adaptive to take a bit more time and be more methodical.”
Berlin demonstrated this conclusion by conducting a test similar to the famous marshmallow experiment (using £80 as the reward rather than a marshmallow) and found that people with orbitofrontal cortex damage tend to be more impulsive than healthy people because they don’t think they have as much time to make a decision. NPY is less effective on them, due to the brain damage.
People with orbitofrontal cortex “respond rapidly to rewards and [punishments] without assessing the consequences sufficiently,” Berlin writes.
So one’s perception of time seems to affect one’s ability to stay calm, to assess a situation, and to make good decisions. As time slows down, these abilities are strengthened. Van Horn found that Gage’s orbitofrontal cortex was severely damaged and Berlin and Morgan’s findings show that this might very well lead to greater stress and a faster perception of time. But does time perception come down to this alone or could there be another explanation as well? Could the answer be found not in neurology, but in psychology?
* * *
In 2009, Aaron Sackett from the University of Chicago gave 37 American undergraduate students a selection of text and asked them to underline each word that had a double-letter combination (for example: “This is anepigrammatic riddle.”) Sackett’s research assistant, Rachel Auer, told the participants that the test would last 10 minutes, then made a show of starting her stopwatch and walking out of the room.
tamping iron that pierced it
(Jedimentat44/Wikimedia Commons)
In the first version of the experiment, Auer walked back into the room after only five minutes with a different, pre-set stopwatch that said 10 minutes had passed. In the second version of the experiment, she waited 20 minutes to re-enter the room, again claiming that 10 minutes had passed. In both experiments, the students rated how fun, engaging, enjoyable, and challenging they found the underlining task.
In a follow-up, two sets of students completed the underlining task over a 10-minute time period. Auer told the first set of students it had lasted five minutes. She told the second set it had lasted 20 minutes. In both the real and the fake “time speed up” scenario, students felt that time had passed faster than it actually had. The students who reported that time flew also reported enjoying the task significantly more. They felt challenged, and seemed to derive pleasure from an otherwise boring task.
Sackett therefore concluded in his paper and in our conversations that simply being told that time is moving quickly might affect the brain’s perception of time as well.
“If you set the expectation [of a certain amount of time having passed] and then their experience doesn’t fulfill that expectation, it’s quite possible that they would engage in this process of misperceiving time,” Sackett says.
It is therefore possible that Gage’s distorted perception of time—that anyone’s distorted perception of time—is as simple as expecting time to pass in a certain way and then finding that it did not. “It certainly fits with the theoretical side of things,” Sackett says.
In another of Sackett’s experiments, he had students watch a movie in a dark room. He set up the start times so the movie would start and end at three different times, each with its own shift in light. “We set up the show times so that the movie either (a) started and ended before dark, (b) started before dark and ended after dark, or (c) started and ended after dark.” He found that the students who started finished watching the movie while it was still light out reported the strongest time distortion. “You can almost imagine them standing there, blinking in the bright sun, and feeling like the past 90 minutes had been compressed into just a short moment.”
Expectation of time, Sackett says, is time perception.
* * *
While working in Chile in the last years of his life, Gage was reported to have made a recovery. Fired from his previous job for rudeness and tardiness, he now seemed a reformed man as a carriage driver and horse groom in Chile. His perception of time seemed to recover—he told friends he felt “temporally adjusted,” according to Macmillan.
Macmillan, his biographer and a psychologist, wrote that Gage’s alleged recovery from a distorted perception of time implies that “damaged [neurological] tracts may re-establish their original connections or build alternative pathways as the brain recovers.”
Van Horn agrees. Changes in time perception may only be temporary, depending on the circumstance.
The tricky thing about Gage is that his case, although groundbreaking and fascinating, is not well-recorded. “Most commentators still rely on hearsay and accept what others have said about Gage, namely, that after the accident he became a psychopath,” MacMillan wrote.
Certainly it’s impossible to know whether Gage really became a psychopath, but the literature that does exist—two medical analyses and various journals of Gage’s friends, family, and coworkers—points to a clear behavioral and time perception shift after the injury. It appears, though, that Gage’s perception of time was not altered until about one decade after the accident when he was in Chile, around 1858, according to Harlow’s postmortem analysis of Gage’s case.
All of the benefits of normal time perception (time “slowing” so people can make more reasoned decisions; time “speeding” when they are taking care of tasks that don’t need their full attention) are still evolutionarily advantageous to a person with orbitofrontal cortex injury—they just don’t come as naturally anymore. Still, there’s great evolutionary incentive to perceive time flexibly, speeding or slowing based on the situation at hand. So evolutionarily advantageous that even a damaged brain may adapt, according to Van Horn.
“The brain is very plastic,” he says. “Nothing else could explain how [Gage] survived for as long as he did.”
Gage’s doctors agreed as well. “I dressed him,” Harlow said. “God healed him.”
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