--Original published at CatherinesCollegeBlog
Researchers recently studied the effects of caffeine on the human brain, specifically looking for an increase in entropy that would make brains better able to handle this unpredictable world. Since people often rely on coffee or tea to keep them focused on a task or give them an energy boost of ideas when they feel stuck, it was originally believed that caffeine must have a lowering effect on entropy levels, creating a more ordered brain system. After performing the study, researchers instead proved the opposite effect.
Researchers began their study by recruiting participants from Hangzhou Normal University in China, as well as from the local community in Hangzhou. Sixty participants formed the sample for the study, including thirty males and thirty females. These participants were required to meet a certain criteria in order to be admitted into the study. They could not have had abnormal structural MRI, they had to be within 20-26 years of age, they could not have any neuropsychological issues or magnetic objects in their bodies, and they could not be taking medications that would affect central blood flow to the brain. Researchers used MRI scans of the brain to detect changes in brain entropy levels of each participant before and after ingesting caffeine. The study was performed over two days and participants were randomly assigned to two groups, A and B, each containing fifteen males and fifteen females. Researchers chose for participants to ingest a caffeine pill instead of having them drink a cup of coffee or tea. This allowed for more control in the experiment, as they knew the exact amount of caffeine each person was ingesting in the 200mg pill. Both groups received a brain scan each day to use as comparison images. Group A received a scan and a caffeine pill on the first day, then returned for another scan the following day so the caffeine had 24 hours to digest. Group B only received a scan on the first day, then was given the caffeine pill the next day along with another scan thirty minutes after ingestion.
What they found was not only an increase in brain entropy, but also a decrease in central blood flow after participants had caffeine within their systems. While central blood flow was reduced across the entire brain, entropy levels only experienced an increase in certain regions of the brain. These regions of increased brain entropy included the default mode network with a 16.09 percent spike, the visual cortex with a 14.48 percent jump, the motor network with an 8.13 percent rise, and the lateral prefrontal cortex with a 7.70 percent growth. Since caffeine is known to have the largest effect on cognitive functions of awareness, movement, and alertness, it made sense that the areas of the brain responsible for the operation of these functions experienced a rise in entropy levels with a little help from caffeine. Including these increased levels of entropy in terms of percentages more clearly operationalized the dependent variable of brain entropy levels, instead of simply stating whether or not they went up; however, the individual data was not provided regarding the increase each participant experienced, which may have been useful. The caffeine pill was the independent variable in the experiment, operationalized based on the amount of caffeine it contained and to some degree, the timing of when participants ingested the pill.
The purpose of this study was to determine the relationship between caffeine and the human brain entropy levels, not whether or not caffeine helps us write a better essay or complete tasks more efficiently. Many people look for the quick fix to a problem or challenge. After reading about a study like this, they likely jump to the conclusion that coffee allows for a higher capacity of the brain to process information. It is important to remember that this was strictly performed as a correlational study, searching for relationships between caffeine and entropy levels, while stumbling upon the effect on central blood flow levels. The increase in entropy and decrease in central blood flow had a correlation ranging from -0.5 to -0.4. Caffeine and entropy were clearly found to have a positive correlation, as participants increased caffeine levels in their bodies and, shortly after, experienced an increase in entropy levels. This correlation currently only allows for suggestions and assumptions, as this study did not specifically experiment with cognitive functions or data relating to this. Correlation does not allow for causation, so while it is acceptable to credit a rise in entropy levels to the ingestion of caffeine, it is not yet scientifically supported to state that caffeine ingestion directly leads to an increase in the brain’s capability to process more complex information.
I first made sure to include more information about the participants, as the news article did not mention any details aside from the number of participants the study used. When data is collected from a group of people, regardless of the study, there will be different results depending on the characteristics of each group. In this case, if the study was performed on people with previous brain injuries or people who are regular coffee or tea drinkers, the results would have likely been different. After only reading the news article at the beginning of this project, I had no idea whether I should be comparing myself and the possible personal effects I would experience as a result of caffeine with the effects and results experienced by the participants. After reading the scholarly article, which included the age, gender, health background, and previous caffeine use of the participants, I can better compare the results to myself and decide how intensely I would like to apply the findings to my own routine. I also made sure to mention the correlational aspect of this study, as it was solely looking for a relationship between the variables. News articles tend to produce more flashy and intriguing writing that sometimes alters the truth a bit. The simple proven fact that caffeine increases brain entropy levels does not also conclude that caffeine increases the information processing abilities of the brain. This was an important distinction that I felt was necessary to include. I left out diagrams of brain scans and their explanations from the scholarly article, simply because they were difficult to understand. A normal person reading this should not have to have a background in psychology or scientific brain imaging techniques in order to understand the main idea. My summary includes what I felt were the most important aspects of the five critical questions for reading research. The news article failed to mention details about the sample group, the timing of the study, and that this was strictly a correlational study. I made these aspects more clear for the reader, so the information could be more accurately applied to his or her personal circumstances. I did not feel that it was critical to include whether or not conclusions are generalized to the right population, since this is still not entirely clear. There need to be further studies done in this same manner, as well as adding the cognitive functioning aspect to collect data about this effect of caffeine before it can be applied to certain groups of people or an entire population.
With the restrictions this assignment involved in terms of word count, I can see why journalists have trouble including every aspect of a research study, especially one like this. There was also a lot of complex scientific data and information included in the scholarly article that would have been difficult to incorporate into a news article. This is likely why journalists of news articles focus more on any attention-grabbing information they can find from the research. People do not necessarily care about caffeine as an antagonist to adenosine, especially since most would not even know what that means. What people are looking for in a news article is any groundbreaking findings they can apply to their own lives, such as how the coffee they drink each day might be making them smarter. I would definitely give credit to journalists who find a way to keep the story intriguing without leaving out critical details of research that establish credibility.
Chang, Da, et al. “Caffeine Caused a Widespread Increase of Resting Brain Entropy.” Scientific
Reports, vol. 8, no. 1, 2018, doi:10.1038/s41598-018-21008-6.
McDonald, Hal. “A Little Chaos With Your Coffee?” Psychology Today, Sussex Publishers, 2
Scholarly Article: https://www.nature.com/articles/s41598-018-21008-6