science fair 2011

Caffeine Buzz

Sarah Hoover

Science Fair 2012

Question: Does decaffeinated coffee provide the same energizing effects as caffeinated coffee?

Hypothesis: The decaffeinated coffee will not provide the same energizing effects as caffeinated coffee because caffeine binds to adenosine receptors. Adenosine is a chemical in the brain which causes feelings of drowsiness. When adenosine receptors are blocked by caffeine, drowsiness disappears. Decaffeinated coffee, not having caffeine, will not affect the brain in the same way.

Background Information: A chemical found in the brain called adenosine binds to adenosine receptors. The binding of adenosine slows down nerve cell activity and causes drowsiness. The more hours of being awake, the more adenosine bonds are formed. When consumed, caffeine binds to the adenosine receptor, so they can no longer sense the adenosine present. The nerve cells speed up their activity and neuron firing increases. The pituitary gland then releases hormones causing the adrenal glands to produce adrenaline. This explains why after drinking coffee, one feels their muscles become tense, feels more alert, and their heart beat increases. Caffeine stimulates the nervous and respiratory system, raises blood pressure, and stimulates blood circulation. Consuming caffeine also releases dopamine in the brain. Dopamine is involved in muscle control. Not enough dopamine and we can’t move, too much and we start twitching, tapping, picking or jerking subconsciously. This is why too much coffee is said to make you ‘jittery’. Dopamine also controls information flow, especially problem solving, memory and focus. This is also why some people feel more collected after having caffeine. Decaffeinated coffee, which doesn’t have caffeine, will not produce the same effects.

Variables:

Manipulated

Whether the subject is given caffeinated or decaffeinated coffee

Controlled

Brand of coffee Ratio of coffee grounds to water Amount of coffee (caffeinated or decaffeinated) given to the subjects Assigned typing test performed twice Amount of time given to drink the coffee Subjects are told the coffee will improve their score Amount of time between drinking coffee and the second typing test

Responding

Score achieved on the typing test

Materials and Design:

Two thermoses Decaffeinated coffee Caffeinated coffee 10 coffee filters Coffee maker Computer with Internet connection 30 Styrofoam cups Measuring cup 30 people willing to participate in the experiment Pen and paper for recording results Label Stickers

Procedure:

1. Prepare caffeinated and decaffeinated coffee with 45 mL (three tablespoons) of coffee grounds and 1.9L (eight cups) of water.

2. Have someone other than yourself mark label stickers “A” and “B”. (This is to ensure the test is a double blind experiment.) Have them apply stickers to the thermos.

3. Have them pour the decaffeinated coffee into either thermos A or B, and caffeinated into the other. Get them to record which one is which.

4. Have your 6 test subjects perform the Astronaut typing test on www.typingtest.com. 5. Record the scores on the first typing test. 6. Pour 177 mL of coffee into Styrofoam cup. Record which thermos it was from. 7. Inform participants the coffee given will improve their score. 8. Give participants the coffee 9. Wait ten minutes after drinking coffee. 10. Have them perform the Astronaut typing test on www.typingtest.com again. 11. Observe and record.12. Repeat until 15 decaffeinated and 15 caffeinated tests have been done.

http://www.typingtest.com/

http://www.typingtest.com/

Observations:

December 2nd

Before Coffee After CoffeeCaffeinated 24 words per minute 32 words per minuteCaffeinated 21 words per minute 36 words per minuteCaffeinated 24 words per minute 26 words per minuteDecaffeinated 28 words per minute 33 words per minuteDecaffeinated 24 words per minute 26 words per minuteDecaffeinated 35 words per minute 37 words per minute

December 5th


December 6th


December 7th


December 8th


December 9th


Average

Before Coffee After CoffeeCaffeinated 34 words per minute 41 words per minuteDecaffeinated 35 words per minute 31 words per minute

The results of these experiments proved that decaffeinated coffee does not provide the energizing effects of caffeinated coffee. In caffeinated tests, 80% of typing speeds increased, while only 60% of decaffeinated typing speeds increased. 20% of scores after drinking caffeinated did decrease, and 40% of scores after drinking decaffeinated decreased as well. Although given decaffeinated coffee, some participants remarked that they were feeling energized and alert. They were surprised to see that they achieved a lower score on the typing test. Some who received caffeinated coffee were surprised to see they achieved a lower score as well. This may be where the placebo effect comes into play. The placebo effect is a measurable difference in experimental results that has no actual cause. People start to feel the effects that an actual treatment would give, just because their expectation to do so is very strong. For example, people know that coffee will energize them, so regardless of what they’re actually consuming they expect to feel energized; and so they do.

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31

Average Words Per Minute Typed Before and After Being Given Caf-feinated or Decaffeinated Coffee

CaffeinatedDecaffeinated

Wor

ds T

yped

Per

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ute

Before After

Analysis:

As shown in the observations, decaffeinated coffee does not provide the same energizing effects as caffeinated coffee. The test subjects given decaffeinated coffee did not achieve as high a typing score as those given caffeinated coffee, because without caffeine the physical and mental components of the body that would have been stimulated were not. The subjects given caffeine were able to achieve a higher score because adrenaline was released, enabling their increased speed and aiding their cognitive skills. When given caffeinated coffee, people are able to type faster and more accurately because they are more alert and aware. Some people’s scores dropped after being given decaffeinated coffee because they may have typed faster in hopes the caffeine would aid them, but in a rush, their accuracy decreased. In other cases, their scores may have decreased just because of the fact that they hadn’t gotten any caffeine to increase their energy levels.

Conclusion:

My hypothesis stating that decaffeinated coffee could not produce the same effect as caffeinated coffee was supported by the data collected. Eighty percent of people drinking caffeinated coffee were able to type with a faster speed, and only sixty perfect of people drinking decaffeinated coffee were able to type with a faster speed than when previously tested. From this evidence, we can infer that caffeinated coffee and beverages will provide energizing effects much more effectively than those not containing caffeine.

Sources of Error:

Sources of error could have included the fact that people were asked to perform the same typing test before and after drinking the coffee. This could have affected the results in the sense that memory played more of a role than caffeine, although caffeine would aid the memory. The participants should have been given at least 20 minutes to drink the coffee, but that amount of time was not possible because of limited access to the typing test. One other source of error could be the possibility that the participants had already consumed caffeine that morning or late in the night. If they were already affected by caffeine or recently went through “caffeine withdrawal”, it would affect their scores and the way the caffeine worked. Whether they were regular coffee drinkers would have a major affect too, as they would have built up a tolerance. The caffeine would not affect them as much. The sample size would have been optimal if at least 50 people, and if a larger range of people, were tested. (For example, testing males and females between the ages of 18-40.) Errors in measurement may have occurred as well.

Application to Society and Future Research:

Knowing that decaffeinated coffee cannot provide the same energizing effects as caffeinated coffee, people may not have a reason to consume decaffeinated coffee anymore. This may change the way people buy products and think about how they will affect their bodies. Future experiments may include testing to see people’s scores approximately 3 hours after consuming the coffee. This would determine whether the temporary effects of caffeine are worth the withdrawal symptoms, including extreme drowsiness and slowed cognitive functions. After comparing results of all three experiment results, the average would be taken and declared the better choice in some situations. Other possible areas to research would be performing strictly physical tests such as running laps, or just mental tests such as a reading comprehension test.

Acknowledgements:

I would like to thank my parents immensely for all the resources, inspiration, and editing help, Mrs. Smith for letting me use the library every morning, and the wonderful Nellies who drank the coffee. I would also like to thank my teachers who guided me down the right path for this experiment.

science fair 2011

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