For five months, every Monday and Friday, Ana Triana Hoyos watched 10 minutes of The Grand Budapest Hotel. It’s not that this Colombian neurologist is an unrepentant Wes Anderson fan. “The movie is good, but when you’ve seen it 30 times it loses its fun,” he explains in a video call interview. He didn’t do it for pleasure, but for work. During these sessions, a device recorded their brain activity. He also did it while performing mental agility and reflex exercises. And while he rested his mind and thought about his things.
The idea was to record the changes in their brain activity during these months and relate them to their physical and psychological activity, which they measured with a phone, a watch and a smart ring. He wanted to study the brain “not as an independent and isolated organ, but rather in relation to external factors.” In this way, Hoyos concluded that exercise, sleep, stress and mood affect brain activity. And these effects resonate in the mind, increasingly weaker, like an echo, a shadow, for about 15 days.
Most studies on the human brain have many participants from whom little data is collected. They take a photograph of a specific moment without taking into account how it evolves over time and how external factors affect it. Hoyos, a neurology researcher at the University of Altos (Finland), was looking for the opposite approach, with the limitations and strengths that this entails. That’s why he decided to study only one brain in depth: his own. The result is published this Tuesday in the scientific journal PLoS Biology.
“There is a very nice analogy that uses [el neurólogo de la Universidad de Harvard] Sebastian Seung,” Hoyos recalls. “Neural activity is like a riverbed, it never remains the same, but rather flows and changes.” Hoyos’ idea, continuing with this simile, was to analyze the current at different times, to compose not so much a photograph, but a video to see how it flows. And also study the external alterations to it. “If I throw a stone in the water today, how will it affect me? What if it rains? “How long will waves continue to occur?” he asks.
For this study, 133 days of behavioral data were collected and 30 fMRI scans were performed that measured attention and memory, (with mental agility games) resting state, and the effects of naturalistic stimuli (the 10 minutes). of The Grand Budapest Hotel). Hoyos’ reflexes and memory were analyzed and related to behavioral, physiological and lifestyle factors. With the most recent ones, from the last week, and with those most distant, from the previous week.
This study is reminiscent of the one carried out almost 10 years ago by Stanford scientist Russell Poldrack, who analyzed his own brain activity for a year and a half to see how external factors (such as caffeine consumption) reprogrammed his brain connections. Hoyos recognizes the similarities between both investigations. But it could be said that they are complementary, since that one took into account food and drink, while the present one focuses on sleep, emotions and sport. Furthermore, these ten years of difference have represented a qualitative leap in technology. In Poldrack’s study, external factors were measured with questionnaires, while the current study used devices that objectively record physiological constants.
“This study shows that external factors can influence, even modifying our brain in some way,” says Jesús Romero, president of the Andalusian Society of Neurology. The neurologist, unrelated to the research, believes that this is important to analyze how the brain makes decisions, how it is modified by learning “and in some way, as an almost more philosophical conclusion, he tells us that it is good to choose a better environment for our brain to permeates and connectivity varies thanks to more beneficial experiences.”
The duality of being a scientist and guinea pig can be “complicated,” Hoyos acknowledges. So that this did not affect the experiment, her team established a very rigid methodology: she could take the data, but not analyze it until the project finished, five months later. It was then that he noticed, for example, the negative effect that lack of sleep had on his brain activity. Restless sleep was correlated with lower connectivity in several brain regions.
It is not that it was a surprising finding, it is something quite intuitive, the expert clarifies. “It’s a bit like proving that water is wet, but how much does it cost to prove, in a scientific way, that water is wet,” he comments. He also certified less expected results, such as physical activity, which clearly and verifiably improved his performance in agility and reflex tests. Or the fact that what was important to perform well was not how many hours one had slept, but the quality of this sleep. “Although of course, this is still a peculiarity of mine,” acknowledges the expert.
This is the main limitation of the study, which explains a specific brain very well, but it is difficult to draw conclusions applicable to everyone. “Psychology exists because no two individuals are alike. If we all were, only biology would exist,” says Ignacio Morgado, professor of Psychobiology at the Autonomous University of Barcelona, who is not involved in this research. “Single-subject studies can be suggestive, but never conclusive.”
Without going down to the fine print and the particularities of Hoyos’s brain, it is possible to think that the persistence of external effects on the brain is something common to everyone. And it is still curious, explains the expert. It would be expected that if you are stressed, if you have slept poorly and have been inactive one day, the next day you will be less agile, and your brain activity will reflect this. What did not seem so obvious is that these effects persisted, like concentric waves in a river, which multiply increasingly weaker and farther from the center. Now, Hoyos wants to investigate how far these waves reach. If they die after two weeks or if they stay, modifying the course of the river in some way. And see if, in the long term, its effects are cumulative. What happens when there are too many. “How many stones do you have to throw to alter the course? Does the river overflow when it has been raining for a long time?”