Fast Food: Can Peppermint Improve Reaction Times?

Project Summary

Difficulty	8
Time required	Long (a couple of weeks)
Prerequisites	An introduction to statistics.
Material Availability	All volunteers must have access to a personal computer with Internet access.
Cost	Very Low (under $20)
Safety	No issues

Share this Project Idea!

Donate to Science Buddies

Sponsor

Sponsored by a generous grant from the Medtronic Foundation

Free 24-Page Booklet
Ideas, activities, career profiles
spark discovery at home & school

www.medtronicfoundation.org

Abstract

Did you know that some teachers give their students a peppermint candy on state testing days? Is it to give the kids sweet-smelling breath? Or are the teachers hoping for something more on the important testing day? In this human biology science fair project, you'll explore whether or not peppermint influences scores on different types of tests.

Objective

To determine if peppermint can improve reactions times during periods of mental fatigue.

Introduction

Click here to watch a video of this investigation, "Breakfast by Cameron and Ashley." This video was produced by DragonflyTV and presented by pbskidsgo.org.

Imagine that tomorrow is a big state testing day. You may feel a little nervous, and your teachers and parents have probably advised you to "get a good night's sleep" and "eat a good breakfast," so that you can do your best. The biggest predictor of success on a test is, of course, the amount of time you spend studying for it, but can other little things, like eating breakfast, give you an edge, too? If you want to watch how a couple of students investigated whether eating breakfast could improve their scores on a memory test, click the DragonflyTV video link on the right, and join Cameron and Ashley as they test their entire classroom.

In this science fair project, you won't be looking at memory tests, but at reaction time tests, and investigating whether eating peppermint can improve reaction times when a person is tired, or under mental fatigue. Reaction time is the time between the start of a sensory stimulus and the time when a person responds to that stimulus. For example, if a person is told to push a button when he or she sees the color red flashed on a screen, the reaction time is the time between when red is first flashed on the screen and the time when he or she first pushes the button. During the reaction time, the person's visual system will see and identify the color red, and then the higher thinking centers will command the motor cortex, in the brain, to send a signal to the arm and hand muscles to push the button. That's a lot going on!

The sensory stimulus does not have to be a visual one, though. Reaction time can be measured as a response to other sensory stimuli, too, such as a sound or a touch. In fact, reaction times to sound have been shown to be faster, on average, than reaction times to visual stimuli. Reaction times have also been shown to be dependent upon many factors, such as a person's:

age,
genetics,
gender,
health,
right or left-handedness,
level of fatigue, and
distractions (other competing stimuli).

For example, reaction times continue to shorten as a child ages. Reaction times reach their fastest point sometime in a person's late 20's. After this age, however, reaction times slowly begin to increase until the 50's and 60's, at which point they begin to increase even more. Reaction times also lengthen if a person is sleepy or mentally fatigued.

The definition of reaction time is presented through a timeline. First, a blank screen is presented to the user. This is followed by flashing a red screen (when measurement of the reaction time begins). In the next sequence, this red screen is detected by the visual system. An image of the brain is then shown given a command to the arm and hand muscles to move. The final tick in the timeline shows a hand pushing a button (when measurement of the reaction time ends).

Figure 1. This drawing shows that reaction time is the time from the presentation of a stimulus (in this example, the stimulus is the red screen) to the time of a reaction to that stimulus (when the hand pushes the button).

In this science fair project, you will look at reaction times during a time of mental fatigue, and see if peppermint has the ability to improve those reactions times. Peppermint is currently used in some school districts in the United States as a snack on state testing days, in hopes that it will help improve test scores. Peppermint aroma has been studied to see if it can increase attention and focus, and even athletic performance. You will study peppermint candies to see if they improve the reaction times of volunteers at a time when they are most drowsy, right before bedtime. So find your favorite peppermint candy and find out if peppermint freshens your breath and your brain!

Terms, Concepts and Questions to Start Background Research

Reaction time
Fatigue
Sensory stimulus
Motor cortex
Distraction
Competing stimuli
Circadian rhythm
Paired t-test
Variation
Normal distribution
Null hypothesis
P-value
Statistical confidence

Questions

What is a memory test?
What is a reaction time test?
How is reaction time measured?
What parts of the body are involved in measuring reaction time?
What factors influence reaction time?
What is circadian rhythm?

Bibliography

This source describes how peppermint candies are used in some school districts:

Aratani, L. (2007, March 20). The Power of Peppermint is Put to the Test. The Washington Post Company. Retrieved November 8, 2008, from http://www.washingtonpost.com/wp-dyn/content/article/2007/03/19/AR2007031901624.html

This source describes how many factors—like age, gender, and handedness—can influence reaction times:

Kosinski, R.J. (2006, September). A Literature Review on Reaction Time. Retrieved November 14, 2008, from http://biology.clemson.edu/bpc/bp/Lab/110/reaction.htm#Fatigue

This source describes paired t-tests and gives four online sites for conducting these tests:

McDonald, J.H. "Paired t-test." Handbook of Biological Statistics, Baltimore: Sparky House Publishing, 2008. 176-180. Retrieved November 14, 2008, from http://udel.edu/~mcdonald/statpaired.html

This source uses a stoplight for a reaction time test:

Weber, J. (2002). The Online Reaction Time Test. Retrieved December 5, 2008, from http://getyourwebsitehere.com/jswb/rttest01.html

This science fair project was inspired by this resource:

TPT. (2006). Breakfast by Cameron and Ashley. DragonflyTV, Twin Cities Public Television. Retrieved December 5, 2008, from http://pbskids.org/dragonflytv/show/breakfastscience.html

Materials and Equipment

Volunteers (at least 50); ideas for where to find all your volunteers include asking classmates, sports team members, family, and friends to participate
All volunteers must have access to personal computers that have the Internet in their homes, as they will be using it right before they go to sleep.
Peppermint candies (1 for each volunteer)
Lab notebook

Experimental Procedure

The first day, have your volunteers familiarize themselves with the online reaction time test by taking the test a few times. In this reaction time test, when the light turns green, the volunteer clicks on a button, and the reaction time is recorded and displayed. After five tries, the volunteer's average is displayed. This test does not allow a person to "jump the gun" and press the button too soon.
The second day, give each of your volunteers a peppermint and have them each take the online reaction time test right before they go to bed. Ask them to
1. Take the full test two times first for practice.
2. Take the full test a third time and record their average reaction time on a piece of paper to give to you.
3. Take the full test a fourth time, but this time have your volunteers put a peppermint candy in their mouths right before they take the test. Ask them to again record their average reaction time on a piece of paper to give to you.
So, you should be getting two scores from each volunteer: one score from when they took the test before bedtime without the use of peppermint, and another score from when they took the test before bedtime while eating peppermint.
After all the volunteers have been tested, you should have two bedtime reaction time scores from each volunteer—one from a trial without the use of peppermint, and one from a trial with the use of peppermint. Enter the reaction times from your volunteers into a spreadsheet program, like Microsoft Excel.
1. In the first column, enter the game score (the average reaction time) when no peppermint was being eaten.
2. In the second column, enter the game score when the volunteers were eating a peppermint as they took the reaction time test.
Be sure that each row has reaction times for the same volunteer. For example, row 1 should have reaction times only for volunteer 1. Row 2 should have reaction times only for volunteer 2.

Conduct a paired t-test on your two columns of data. You can read more about how to conduct a paired t-test at websites listed in the Bibliography, above, or you can often find one in software that handles spreadsheets. Paired t-tests are often used in situations where you are measuring one variable, like body temperature, and have two points of observation in the same person; for example, both before and after a medical treatment to lower body temperature. People react differently to the same treatment. Some may show a big response, while others may show little response. The paired t-test is a powerful test when the difference in the measurement variable between the before and after groups is small compared to the variation within a group.
The null hypothesis is the statement that you will be testing with the paired t-test to see if the two data sets (reaction times before and after the peppermint) are (statistically) the same. Your null hypothesis is that the mean difference between the paired measurements is zero. The paired t-test will return a p-value.
1. If p < 0.05, then you can say that the two columns of data are significantly different and that the peppermint affected reaction times.
2. If p > 0.05, then the two columns of data are not significantly different.
The lower the p-value, the greater your statistical confidence that the data sets are different.

Variations

Reaction times have been shown to follow a circadian rhythm. Develop an experiment to determine if there is a correlation between reaction times and body temperature.
Develop an experiment to determine if reaction times have greater statistical variation in children than in adults. For each volunteer, you will need to collect all the reaction times from the game, not just the averages, for this variation.
To try other science fair projects about reaction times, try these Science Buddies science fair projects:
- Think Fast!
- Think Fast: Do Video Game Players Have Faster Reaction Times Than Non-Players?

For more science project ideas in this area of science, see Human Biology & Health Project Ideas.

Credits

Kristin Strong, Science Buddies

Last edit date: 2008-12-26 11:17:00

Career Focus

If you like this project, you might enjoy exploring careers in Human Biology & Health.

Medical & Clinical Laboratory Technician
Doctor's need information to decide if a person is healthy or sick, if a baby's earache is bacterial or viral, or if the man next door needs medication to lower his cholesterol and prevent a heart attack. The information often comes in the form of results from lab tests. Medical and clinical laboratory technicians are the people who perform these routine medical laboratory tests, giving the doctors the information needed to diagnose, treat, and prevent disease. Physician
Physicians work to ease physical and mental suffering due to injury and disease. They diagnose medical conditions and then prescribe or administer appropriate treatments. Physicians also seek to prevent medical problems in their patients by advising preventative care. Ultimately, physicians try to help people live and feel better at every age.

Health Educator
Have you ever heard the expression "Prevention is the best medicine"? Prevention is the fundamental work of all health educators. They attempt to prevent illnesses or diseases in individuals or entire communities through education about nutrition, exercise, or other habits and behaviors. Health educators present scientific information in ways that their audience can relate to, and are sensitive to cultural differences. They are the cornerstone of the public health system, improving health and saving thousands of lives by motivating changes in behavior. Registered Nurse
Registered nurses have been called the backbone of our health-care system. Working on the front lines of medical care, they treat patients, monitor and record their condition, help establish a plan of care, educate patients or the public about a medical condition, and provide advice and emotional support to patients’ family members. Registered nurses are highly observant and detail-oriented, and are often the first to catch important and changing signs and symptoms. Many nurses specialize in one or more types of medicine, such as emergency care, hospice, labor and delivery, psychiatry, surgery, or wound care.

Physical Therapist
If you are injured in an accident, suffer a stroke, heart attack, or loss of a limb, or are born with conditions that make it difficult to move your body, then you will often be cared for by a physical therapist. Physical therapists review a patient's medical history, test and measure his or her physical condition (things like range of motion, strength, flexibility, balance, coordination, muscle function), and then develop a treatment plan to meet some physical goals. They coach, motivate, and educate the patient to follow the plan and work on therapies that will restore, maintain, or promote physical fitness and health. Physical therapists also act as advocates, bringing a patient's health needs to the attention of other workers on a patient's healthcare team, such as physicians, speech therapists, or respiratory therapists. Audiologist
On each side of your head is the auditory system, one of the most beautifully designed organs in the human body. The auditory system not only detects sound, but is closely tied to the vestibular system, which helps a person with balance, and knowing how his or her body is moving through space. Audiologists detect, diagnose, and develop treatment plans for people of all ages who have problems with hearing, balance, or spatial positioning. This important work impacts how well a person is able to communicate and function at home, school, and work.

Emergency Medical Technicians and Paramedic
Emergency medical technicians and paramedics belong to a group of healthcare workers known as first responders. They are among the first people to respond to an accident or emergency, providing pre-hospital care for conditions such as heart attacks, strokes, gunshot wounds, childbirth, or falls. Although this work is physically and emotionally demanding, many emergency medical technicians and paramedics enjoy the challenges and the satisfaction of knowing their work is critical in saving lives. Respiratory Therapist
In any medical emergency, health care workers first check a patient's airway and breathing, since oxygen is the first thing needed to survive. Respiratory therapists specialize in treating airway and breathing problems. They help, for example, premature infants whose lungs are poorly developed, or children and adults with asthma or pneumonia. They also treat people who have had heart attacks or who have been in swimming or other accidents. Their critical work helps to provide the breath of life.

Pharmacist
Pharmacists are the medication experts. They advise doctors, nurses, and patients on the correct drug dosage for a patient's weight, age, health, and gender; on interactions between drugs; on side effects; on drug alternatives; on costs; and on ways to give drugs. They also dispense drugs at pharmacies, according to prescriptions, checking for dangerous drug interactions, and educating patients on how to take drugs, what reactions to watch out for, and how long it should take for drugs to work.

Join Science Buddies
Become a Science Buddies member! It's free! As a member you will be the first to receive our new and innovative project ideas, news about upcoming science competitions, science fair tips, and information on other science related initiatives.

Support Science Buddies
If this website has helped you, won't you consider a small gift so we may continue developing resources to help teachers and students?

	Medical & Clinical Laboratory Technician Doctor's need information to decide if a person is healthy or sick, if a baby's earache is bacterial or viral, or if the man next door needs medication to lower his cholesterol and prevent a heart attack. The information often comes in the form of results from lab tests. Medical and clinical laboratory technicians are the people who perform these routine medical laboratory tests, giving the doctors the information needed to diagnose, treat, and prevent disease.			Physician Physicians work to ease physical and mental suffering due to injury and disease. They diagnose medical conditions and then prescribe or administer appropriate treatments. Physicians also seek to prevent medical problems in their patients by advising preventative care. Ultimately, physicians try to help people live and feel better at every age.

	Health Educator Have you ever heard the expression "Prevention is the best medicine"? Prevention is the fundamental work of all health educators. They attempt to prevent illnesses or diseases in individuals or entire communities through education about nutrition, exercise, or other habits and behaviors. Health educators present scientific information in ways that their audience can relate to, and are sensitive to cultural differences. They are the cornerstone of the public health system, improving health and saving thousands of lives by motivating changes in behavior.			Registered Nurse Registered nurses have been called the backbone of our health-care system. Working on the front lines of medical care, they treat patients, monitor and record their condition, help establish a plan of care, educate patients or the public about a medical condition, and provide advice and emotional support to patients’ family members. Registered nurses are highly observant and detail-oriented, and are often the first to catch important and changing signs and symptoms. Many nurses specialize in one or more types of medicine, such as emergency care, hospice, labor and delivery, psychiatry, surgery, or wound care.

	Physical Therapist If you are injured in an accident, suffer a stroke, heart attack, or loss of a limb, or are born with conditions that make it difficult to move your body, then you will often be cared for by a physical therapist. Physical therapists review a patient's medical history, test and measure his or her physical condition (things like range of motion, strength, flexibility, balance, coordination, muscle function), and then develop a treatment plan to meet some physical goals. They coach, motivate, and educate the patient to follow the plan and work on therapies that will restore, maintain, or promote physical fitness and health. Physical therapists also act as advocates, bringing a patient's health needs to the attention of other workers on a patient's healthcare team, such as physicians, speech therapists, or respiratory therapists.			Audiologist On each side of your head is the auditory system, one of the most beautifully designed organs in the human body. The auditory system not only detects sound, but is closely tied to the vestibular system, which helps a person with balance, and knowing how his or her body is moving through space. Audiologists detect, diagnose, and develop treatment plans for people of all ages who have problems with hearing, balance, or spatial positioning. This important work impacts how well a person is able to communicate and function at home, school, and work.

	Emergency Medical Technicians and Paramedic Emergency medical technicians and paramedics belong to a group of healthcare workers known as first responders. They are among the first people to respond to an accident or emergency, providing pre-hospital care for conditions such as heart attacks, strokes, gunshot wounds, childbirth, or falls. Although this work is physically and emotionally demanding, many emergency medical technicians and paramedics enjoy the challenges and the satisfaction of knowing their work is critical in saving lives.			Respiratory Therapist In any medical emergency, health care workers first check a patient's airway and breathing, since oxygen is the first thing needed to survive. Respiratory therapists specialize in treating airway and breathing problems. They help, for example, premature infants whose lungs are poorly developed, or children and adults with asthma or pneumonia. They also treat people who have had heart attacks or who have been in swimming or other accidents. Their critical work helps to provide the breath of life.

	Pharmacist Pharmacists are the medication experts. They advise doctors, nurses, and patients on the correct drug dosage for a patient's weight, age, health, and gender; on interactions between drugs; on side effects; on drug alternatives; on costs; and on ways to give drugs. They also dispense drugs at pharmacies, according to prescriptions, checking for dangerous drug interactions, and educating patients on how to take drugs, what reactions to watch out for, and how long it should take for drugs to work.