The Effect of Caffeine on Psychomotor Performance

THE EFFECT OF CAFFEINE ON PSYCHOMOTOR PERFORMANCE

Maria Cuevas and Catalina Munoz

Dept. of Biological Sciences, Saddleback College, Mission Viejo, CA 92692

Abstract

Caffeine is known to be a central nervous system (CNS) stimulant that can improve alertness and treat drowsiness (this sentence makes drowsiness sound like an illness). In this study, three products, one containing caffeine, one with non-caffeine, and water are tested to see if caffeine has a positive effect on reducing reaction time. The products included a Coca-Cola can with caffeine, a Coca-Cola can without caffeine, and water

(this sentence is just a repeat of the sentence before it. You could put the brand names in parenthesis). Both Coca-Cola cans contain the same ingredients with the exception of caffeine. Since caffeine is known to be a stimulant it was expected that the Coca-Cola with caffeine would have a decrease in reaction time. Each product was tested by having a participant in the study drink Coca-Cola, non-caffeine Coca-Cola, and water over a course of three days. The participant took a reaction test prior to consuming the specific drink. Then from the time the drink was finished and waiting 10 minutes they took the reaction test again. The p-value for the average difference among the 3 groups was 0.057 which is greater than 0.05 (did you guys run an ANOVA or t-test? This sounds like you did a t-test). Thus this meant that there was no significant difference between the groups, so the results do not support the hypothesis that caffeine decreased reaction time. Introduction

. Caffeine is mainly consumed to help enhance alertness and also used to help with physical activity because it acts as a stimulant to the central nervous system.

Caffeine has been shown to improve sprint time, anaerobic power, and reaction time, all integral aspects of agility (Lorino, 2006). Many people consume caffeine when they are suffering from drowsiness and are un-alert (un-alert? Revise maybe) throughout the day.

In 2007–2010, average daily reported caffeine intake was just under 150 mg for the 18–

29 year age group (Wesensten, 2014). Caffeine is a naturally occurring alkaloid found in the seeds, leaves, and fruit of coffee, tea, cocoa, maté, guarana, kola nuts, yerba maté, and more than 60 other plants (you can probably just mention tea, coffee and cocoa.).1,2

Caffeine (numbers at beginning of sentence. I know it’s the name of the compound but consider revising so it’s not at the beginning of the sentence) is also added to a number of products for its known stimulant effects (Bailey et al, 2014). Since caffeine is a stimulant it is added to energy drinks, capsules, tablets, and energy shots for an energy boost. It is also found in soda, chocolate, coffee, and tea because leaves that are used in the products naturally contain caffeine (didn’t you already mention this?). Specifically in caffeine drinks such as colas are known to offer not only caffeine but also a hefty (maybe give a value instead of “hefty”) dose of sugar (Clark, 2014). The expectation of people on the product also has an impact on an increase in cognitive performance. (Irmak et al, 2005).

Since participants know that they are drinking caffeine their reaction time may slightly decrease. (Explain this since it’s very important for your study) (Indent) The objective of the experiment will determine if caffeine helps decrease reaction time (revise this sentence). Coca-Cola will be consumed by volunteer participants and then they will take a reaction time test to see if time decreases or increases (You don’t need to out methods in the intro). Then on another day the same group of volunteers will drink non-caffeine Coca-Cola and take the reaction test. On the final day they will drink water and take the reaction test. The groups will then be compared see if caffeine has an effect on reaction time or if the other ingredients also contributed to the effect of reaction time. The results will help the investigators determine if caffeine has an impact on the psychomotor performance of people (you guys say “help” a lot).

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Materials and Methods

The experiment took place over a period of 5 weeks (October 26, 2015 to

November 27, 2015) in the Biology lab and Learning Resource Center at Saddleback

College (Mission Viejo, CA). Two 12 pack of 12 ounces of Coca-Cola cans and two 12 pack of 12 ounces of Coca-Cola caffeine-free were purchased at the Target on

Jeronimo in Mission Viejo, on October 25, 2015 the day prior to experiment. The ingredients in the 12 ounces of Coca-Cola are carbonated water, high fructose corn syrup, caramel color, phosphoric acid, natural flavors, and caffeine. The caffeine-free

Coca-Cola contained the same ingredients except for the caffeine.

The 30 volunteers were asked to consume a specific drink. They were asked to drink either 8 ounces of Coca-Cola, Coca-Cola caffeine-free, or water. After choosing what drink they would consume that day the other two drinks would be consumed on a later day. Before participating in the experiment each participant was asked to sign a consent form. At the beginning of the experiment each volunteer was asked not to drink any sort of caffeine and be on a non-fasting diet. The participants would then take an online reaction test provided by the University of

Washington between the hours of 8:00am-11:00am. The online reaction test consists of a stoplight that starts on red and then randomly changes to green. Each participant was asked to take the test and when he or she saw the color change hit the button to record their reaction time. The participants took the reaction test 10 times in order to record the average. After completing the drink they did for that day they would consume the other two drinks later on separate days and repeat the process as they did for the first drink. (You should mention when the participants did drank and took the test. You just said they drank then took a test then drank again on a later day)

When the volunteer(s) arrived to participate in the experiment they were first asked to take the test without drinking any of the specified drinks first and the average reaction time was recorded. Once they were finished taking the test they were then given 8 ounces of a specified drink to consume and would have 10 minutes to finish it. Once they had finished their drink they would wait and additional 10 minutes from the time they had finished consuming the drink. After the 10 minutes was finished they took the online reaction test again and the average reaction time was recorded.

Results The average reaction time for the experimental group and the control group was used to obtain the result in Figure 1. There were 3 different time groups for with and without the specified drink As indicated in figure 1, each group reaction time slightly decreased after drinking (the) specified drink with the exception of water staying relatively the same. The three group times without the drink were compared to each other. ANOVA test was run on the three without the drink and the p value was 0.935. ).

The Bonferroni Correction test indicated since p>0.05 that there is significant difference between the data. The three with drink were also compared using. ANOVA test and the p value was 0.119). The Bonferroni Correction test indicated that p-value is greater than

0.05 that there is no significant difference between the data. (Revise this section. A few sentences can be worded better)

To determine if there was a decrease in reaction time the groups with the drink were subtracted by the groups without the drink. (In your methods you didn’t mention that subjects took a test after not drinking anything) For example (I would “for example out. This is how you calculated your data) the reaction time with Coca-Cola was subtracted from the reaction time of without Coca-Cola. The difference for each group was then averaged to find the results in Figure 2. ANOVA test was run and the resulting p-value 0.057 which is greater than 0.05 and indicates that there is no significant different between the groups. (There is not one value in the results section other than p value.

What were the actual time differences?)

Figure 1. This graph shows the average reaction time of the six different groups for with and without the drink (did subjects not drink anything?). The average reaction time was faster with the Coca-Cola, Coca-Cola caffeine-free, and water than without. Error bars are mean + SEM. Figure 2. The graph shows the average difference of the reaction time between without and with the specified drink. Error bars are mean + SEM. (p values, actual mean values? you guys need to mention these numbers)

Discussion

The purpose of this experiment, reaction time was measured as the average difference between without and with (experimental) for Coca-Cola to see if reaction time decreased with caffeine. Caffeine enhanced physical performance (faster tapping speed and faster simpler and choice reaction times) in both medium-high and non-low consumers (Rogers et al, 2013) (This sentence sounds like you found these results. You need to mention this was not done by your study) . In some cases it did increase reaction time while others it did not affect (Same edit as sentence before). This could be caused by the fact that some of the participants consume caffeine on a daily basis. Frequent consumption fails to enhance mental alertness and mental performance (Rogers et al,

2013). This seemed to be the case for some of the participants. (This needs to be revised heavily. It sounds like you are making claims from the data you found in your study. You have to mention these were results found from other studies. Not just cite them)

The water acted as a control to see if there would be a significant difference between the Coca-Cola and Coca-Cola caffeine-free. However in some the reaction time had decreased when participants were given water to drink (revised this sentence). This could be due to the fact of the learners curve. The learners curve theory is that individuals get better with practice (revise this sentence. “the learners curve theory is that” doesn’t sounds right). Personal experience tells them that the more derivatives they work, the easier it is to do —that changing a tire is easier the second time than the first time (Neely et al, 2010) (This sentence sounds you copied and pasted). Since the participants took the test a second time after consuming their drink they knew what to expect rather than the first time. (You need to explain why. You guys are stating facts but not supporting them.

A citation is not the same as supporting your claim. You should show that you know why they found the results they did)

The statistical test run on the groups without the drink and the three with the drink indicated that there was no significant difference between the products. Both of the p- values of the ANOVA test had a greater value than 0.05. The ANOVA test that was run on the average difference between the groups of without and with the drink also showed that there was no significant difference (p=0.057, Figure 2). Since there was no difference between the groups the results did no support the hypothesis that caffeine would decrease reaction time. (This should be revised and placed at the top of the discussion or in the results)

Further research on the effect of caffeine on decreased reaction time could expand on the result of the current study (Your study?). This study was limited to the number of participants and the participants aware that they are consuming caffeine (revise). Also the intake of caffeine on a daily basis of each participant limited the effect caffeine had on the individual (Why? How do you know that?). By making them unaware of which product has caffeine and having more participants that do not consume caffeine as often as others may lead to more consistency. (The discussion need to be an explanation of the data you found and analyze the possible reasons you found what you did and tell us why.

You have tell us why. Citing another person’s study does not replace the need to explain why) Literature Cited

Bailey, Regan L. Saldanha, Leila G. Gahche, Jaime J. Dwyer, Johanna T. 2014.

Estimating Caffeine Intake From Energy Drinks and Dietary Supplements in the

United States. Nutrition Reviews 72: 9-13

Clark, Nancy. 2014. Caffeine: performance enhancement in a mug. Palaestra. 28.3 (Fall

2014): 53

Irmak, Caglar. Block, Lauren G. Fitzsimons, Gavan J. 2005. The Placebo Effect in

Marketing: Sometimes You Just Have to Want It to Work. Journal of Marketing

Research. 42 (4): 406-409

Lindsey, Matthew D., and Concha R. Neeley. “Building Learning Curve And Script

Theory Knowledge With Lego.” Marketing Education Review 20, no. 1 (Spring

2010 2010): 71-75.

Lorino, Andrew J. Lloyd, Lisa K. Crixell, Sylvia H. 2006. The Effect of Caffeine on

Athletic Agility. Journal of Strength and Conditioning Research. 20 (4): 851-854

Online Reaction Test [Internet]. University of Washington; c2000-2015 [cited 2015 November 28]. Available from: https://faculty.washington.edu/chudler/java/

redgreen.html

Rogers, Peter, Susan Heathereley, Emma Mullings, and Jessica Smith. 2013. “Faster but

not smarter: effects of caffeine and caffeine withdrawl on alertness and

performance.” Psychopharmacology 226, no 2: 229-240.

Wesensten, Nancy J. 2014. Legitimacy of Concerns About Caffeine and Energy Drink

Consumption. Nutrition Reviews 72: 78-86. Review Form Department of Biological Sciences Saddleback College, Mission Viejo, CA 92692

Author (s): Maria Cuevas and Catalina Munoz

Title: THE EFFECT OF CAFFEINE ON PSYCHOMOTOR PERFORMANCE

Summary Summarize the paper succinctly and dispassionately. Do not criticize here, just show that you understood the paper. The study was testing the effect that caffeine had on reaction time of human volunteers. They found that there was no difference between the reaction times for consuming water, caffeinated soda and non-caffeinated soda.

General Comments Generally explain the paper’s strengths and weaknesses and whether they are serious, or important to our current state of knowledge.

The biggest strength in the paper is the methods I suppose, but even those were difficult to understand at times. There was mention of participants that didn’t drink anything and then took the reaction time test which wasn’t mentioned anywhere else or on any figures in other sections. There was order in which the participants drank the different drinks or how many days were in between each test. There was no mention of how much sleep the volunteers got before taking the test or what time of day they took the test (Morning, evening, night). The intro was very short and had abrupt transitions from topic to topic. Nothing was really explained. Facts were mentioned but not explained or elaborated on. The results sections needs to be revised heavily. There is only one value in it and it’s the results of the ANOVA test. There was no mentions of actual reaction times, difference in times from one drink to the other. Figure captions don’t explain the graph at all. They just say what the axis titles are. The Discussion is not really a discussion. This is the section where you need to explain why you found what you did, and there wasn’t really any of that in there. And if there mention of a reason why, it wasn’t explained, it was just stated. Also not once was it written in the discussion that the results they described from other studies were in fact from other studies. It sounded like they were results they found. There is no conclusion section. This paper needs to be revised. It’s also very short. Considering it’s a paper on studying the effect of caffeine on the brain, there is so much more to talk about than what is present in this paper. The paper was very difficult to understand.

Technical Criticism Review technical issues, organization and clarity. Provide a table of typographical errors, grammatical errors, and minor textual problems. It's not the reviewer's job to copy Edit the paper, mark the manuscript.

This paper was a final version This paper was a rough draft

There were a lot of grammatical and textual problems with the paper (No comas, fragments, odd sentences, capitalizations, all headings, title). The organization was poor. Each section just sounded like a repeat of the section before it. The sections, especially the intro and discussion, lacked information and explanation. This paper needs to be revised heavily. It cannot be turned in this way. The topic is interesting but the paper does a very poor job of telling anyone why. Also it sounds like a few sentences were copied and pasted from another paper because they were jarring and didn’t match how the rest of the paper was written.

Recommendation

 This paper should be published as is  This paper should be published with revision  This paper should not be published