The Effects of Caffeine on the Human Brain

Description of the Project

My project is on the effects of caffeine on the general and specific parts of the human brain. In order to test this, I got six (6) volunteers from my grade that all had the same amount of sleep on average. Next, in order to get the most centralized results, I eliminated body mass and height, thanks to having them ingest a certain amount of caffeine according to their Basal Metabolic Rate. I used the BMR calculator at I asked my volunteers to fill this test out at home in private, and just give me their BMR in calories per day, at the start of the experiment – therefore no one would need to know their weight and height. To work backwards from the BMR would be almost impossible. This was so that I could measure how much caffeine to give my participants. The amount of caffeine each participant ingested was 5mg of caffeine for every 100 calories per day. So if someone’s BMR was 1500 calories/day, then they would receive 15*5 = 75 mg of caffeine. The highest amount of caffeine given was 85 mg. So essentially, the 6 participants would do the three tests that involved the three different parts of the brain, and then they ingested caffeine, and redid the tests. The tests themselves were computer generated and were a little different every time. The three tests I had my volunteers do are a sequence memory test (where the computer would flash a random sequence of lights and the participants had to repeat them), a face matching test (where two random pictures of two faces from different angles would flash for a few seconds and the participants had to see if they were the same face) and a reflex test (where the participants would be asked to click on their mouse as fast as they could when the light in front of them turned green). The type of caffeine ingested was normal Extra Large Tim Horton’s Coffee. In 700 ml of this coffee there were 330 mg of caffeine. Participant 1 and 3 (both girls) had 60 mg of caffeine each. Participant 5 (also a girl) got 65 mg of caffeine. Participant 2 (boy) got 75 mg of caffeine. Participant 4 (boy) got 85 mg of caffeine and participant 6 (boy) got 70 mg of caffeine. Because BMR’s are not whole numbers on average, I rounded each person’s BMR to the nearest hundred. Even though I eliminated this obstacle, the results varied thanks to genetics and other factors out of my control. The coffee was black. No added sugar or milk. I just wanted to know if ingestion projects were allowed at the Canadian Science where if I had the consent forms and the ethics forms completed.


The National Ethics Committee congratulates the Regional Science Fair and the others who have mentored this project.  Great care has been taken to ensure it is in compliance with the Ethics rules on caffeine.

The Ethics Policy on Caffeine is available here:

It requires:

1) No participants under 10 years of age
2) No more than 85 mg of caffeine to participants under 13.
3) Everyday food item such as coffee
4) Monitored by adult supervisor.
All the usual elements of a Low Risk Human project also need to be met, including:
- Written Informed consent
- Written parental consent
- Letter of Information
- Participants must not be taking prescription medications.

This projects fulfils these requirements, and so is eligible for presentation as science fairs in Canada.