The factor that is observed and measured for change in an experiment, thought to be influenced by the independent variable; also called the outcome variable.
hypothesis
A tentative statement about the relationship between two or more variables; a testable prediction or question.
independent variable
The purposely manipulated factor thought to produce change in an experiment; also called the treatment variable.
random assignment
The process of assigning participants to experimental conditions so that all participants have an equal chance of being assigned to any of the conditions or groups in the study.
stress
A negative emotional state occurring in response to events that are perceived as taxing or exceeding a person’s resources or ability to cope.
Think Like a Scientist
Coping with Stress
By:
Susan A. Nolan, Seton Hall University
Sandra E. Hockenbury
REFERENCES
Benson, Herbert. (1975). The relaxation response. New York: Avon.
British Airways Media Centre. (2014). Paws and relax [Press release]. Retrieved from http://www.britishairways.com/en-gb/bamediacentre/newsarticles?articleID=20140904165040&articleType=LatestNews#.VN1RPyhTPA5
Frumkin, Howard. (2001). Beyond toxicity: Human health and the natural environment. American Journal of Preventive Medicine, 20, 234–240.
Kushlev, Kostadin, & Dunn, Elizabeth W. (January 11, 2015). Stop checking email so often. The New York Times. Retrieved from http://www.nytimes.com/2015/01/11/opinion/sunday/stop-checking-email-so-often.html
Kushlev, Kostadin, & Dunn, Elizabeth. (2015). Checking email less frequently reduces stress. Computers in Human Behavior, 43, 220–228.
Latas, Milan; Pantic, Marina; & Starcevic, Vladan. (2011). Predictors of fear of flying. European Psychiatry, 26, 1–163. doi:10.1016/s0924-9338(11)71874-0
Ohkura, Michiko; Goto, Sayaka; Higo, Asami; & Aoto, Tetsuro. (2011). Relationship between kawaii feeling and biological signals. Transactions of Japan Society of Kansei Engineering, 10, 109–114.
Wells, Deborah L. (2005). The effect of videotapes of animals on cardiovascular responses to stress. Stress & Health: Journal of the International Society for the Investigation of Stress, 21, 209–213.
FAQ
What is Think Like a Scientist? Think Like a Scientist is a digital activity designed to help you develop your scientific thinking skills. Each activity places you in a different, real-world scenario, asking you to think critically about a specific claim.
Can instructors track your progress in Think Like a Scientist? Scores from the five-question assessments at the end of each activity can be reported to your instructor. To ensure your privacy while participating in non-assessment features, which can include pseudoscientific quizzes or games, no other student response is saved or reported.
How is Think Like a Scientist aligned with the APA Guidelines 2.0? The American Psychological Association’s “Guidelines for the Undergraduate Psychology Major” provides a set of learning goals for students. Think Like a Scientist addresses several of these goals, although it is specifically designed to develop skills from APA Goal 2: Scientific Inquiry and Critical Thinking. “Coping with Stress” covers many outcomes, including:
Interpret, design, and conduct basic psychological research: Define and explain the purpose of key research concepts that characterize psychological research [identify independent and dependent variables in a study]
Interpret, design, and conduct basic psychological research: Describe research methods used by psychologists including their respective advantages and disadvantages [consider the conditions under which research findings apply to real-life situations]
13.2Introduction
This activity invites you to test the claim, made by British Airways about their new Paws and Relax inflight TV channel, that videos of cats and dogs can help people cope with stress during a flight. First, you’ll rate your own level of stress before and after watching an animal video. You will then examine evidence on whether watching animal videos can decrease stress. You’ll consider alternative explanations for why these findings might not directly apply to British Airways’ channel. And you’ll think about the sources of information on the stress-reducing qualities of animal videos—a company like British Airways versus a peer-reviewed journal article.
13.3Identify the Claim
1
Identify the Claim
13.3.1Stress on a Plane
Does flying make you anxious? 60.6% of participants in one study reported some level of anxiety about flying (Latas & others, 2011). Flying might make you feel stressed for several reasons. You may worry about missing your flight, suffering through the discomfort of economy class, or even the highly unlikely occurrence of a plane crash.
Does flying make you stressed? Look at these photos of stressful experiences associated with flying. How would you feel if you were rushing to catch a flight?
ColorBlind Images/Getty Images
Philippe TURPIN/Getty Images
Andrei Spirache/Getty Images
estherpoon/Shutterstock
13.3.2Check Your Heart Rate
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What effect do feelings of stress have on us? Although stress is an emotional state, it can affect physical responses. In the lab, researchers use many physical indicators, such as increased cortisol levels in saliva or accelerated heart rate, to assess people’s level of stress. If thinking about awful air travel experiences made you feel stressed, that might show up in your heart rate. Let's measure your heart rate now by checking your pulse. Read the instructions in this diagram to learn how. When you are ready, click the timer and begin checking your pulse. There will be a five-second countdown before the timer begins.
Your heart rate is XX beats per minute. We calculated that by multiplying your 20-second heart rate by three. The resting heart rate for most people falls between 60 and 100 beats per minute.
13.3.3A Stress-Reducing Animal Video?
Recognizing the elevated stress that many passengers experience, one airline is trying to help its passengers cope. British Airways introduced an in-flight channel called Paws and Relax, which is dedicated to videos of adorable dogs and cats. In a promotional video for Paws and Relax, the British Airways in-flight entertainment manager stated that the initiative is based on research that “watching images of cute animals can actually lower your heart rate and reduce stress levels” (British Airways Media Centre, 2014).
British Airways
13.3.4Watch and Relax
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Were you feeling stressed when you thought about flying? If you were feeling stressed for any reason, do you think watching British Airways’ Paws and Relax videos would help you cope with your stress? Would it lead to a lower heart rate? Let’s see if watching a video of cute animals will do the trick. Don’t multitask while you watch this video. Sit quietly, breathe normally, and focus on the animals in this footage.
Did it work? Do you feel less stressed? Let’s check your heart rate now. Once again, find your pulse on your wrist, and then click the 20-second timer to begin. As before, there will be a five-second countdown before the timer begins.
Your heart rate is now XX beats per minute. That’s [slower than, the same as, faster than] your heart rate before you viewed the video.
13.3.5A Claim about Stress Reduction
It’s possible that you had a slower heart rate after watching the video. Identify the claim that British Airways is making, and that you explored, in part, by measuring your heart rate after thinking about the stress of flying and again after watching a video of cute animals.
British Airways is claiming that watching cute animal videos can lower your heart rate and help you cope with feelings of stress associated with flying. This is why they’re adding an animal channel to their in-flight entertainment selection. You tested this out on your own heart rate just now. But remember, scientific research applies to people in general, not to any individual person. Even if this claim is supported by evidence, there will still be people for whom cute animal videos do not measurably reduce stress. It’s also possible that this brief video isn’t enough to lead to a decreased heart rate. You may have to watch for a while. There may even be some people for whom the videos increase stress—people afraid of animals, for example! Finally, some researchers have observed an increased heart rate in people who have experienced “kawaii feeling,” based on the Japanese word for “cute, lovable, and small” (Ohkura & others, 2011). It is possible that kawaii feeling, and a related increase in heart rate, might be induced by watching cute animals.
Tiger's Pride/Shutterstock
13.4Evaluate the Evidence
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Evaluate the Evidence
13.4.1A Study on Animal Videos and Stress
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Have you noticed that spending time with pets can be relaxing? This effect is well documented by research (Frumkin, 2001). But interacting with animals is different from watching videos of animals. To test British Airways’ claim that watching animal videos can reduce stress levels, we need to think like a scientist and examine research that tested the effects of animal videos on stress.
One researcher has conducted such an experiment (Wells, 2005). Psychologist Deborah Wells randomly assigned 100 participants to watch one of five videos, all with the goal of relaxation. So, the independent variable was type of video. The three experimental conditions had videos of non-human animals: fish, birds, or monkeys. There were two control conditions—one with a video of humans, and another with a blank-screen video. All videos lasted 10 minutes and all (except, of course, the blank screen) showed mostly slow movements. There was no sound.
Which videos were experimental conditions and which were control conditions? Click to identify.
Grigorev Mikhail/Shutterstock
An aquarium in which ten neon tetras are swimming around plants and rocks
cobalt88/Shutterstock
A blank screen
Ronald Wittek/age fotostock
A zoo exhibit in which ten black-and-white colobus monkeys are sitting in trees, climbing, and grooming themselves
PrakapenkaAlena/Shutterstock
An aviary in which ten parakeets are flying around and sitting on perches
Jim Purdum/Getty Images
A soap opera episode in which five people are sitting and talking with each other
13.4.2Cause and Effect?
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After watching the videos, all participants read a difficult passage out loud for ten minutes. This task was designed to be stressful, and it worked. But Wells hypothesized that participants who watched animal videos first would feel more relaxed than those who did not. To see whether this was true, Wells assessed participants' heart rates and blood pressure throughout the experiment.
Before we look at Wells’ conclusions, let’s think about whether it’s possible to demonstrate a cause-and-effect relationship based on this evidence. The experimental design appears sound: participants were randomly assigned to one of five different groups, including two control groups. Across all groups, Wells varied only one factor; this is the independent variable. She then measured the dependent variables: changes in heart rate and blood pressure occurring during the experiment. Because those changes depend only upon a single variable, it is possible to say that they were caused by the independent variable.
13.4.3Which Video Was Most Protective Against Stress?
hockenbury_tls_ch13_coping_with_stress_3
After you watched the animal video at the beginning of this activity, your 20-second heart rate
[decreased from XX to XX; increased from XX to XX; stayed the same].
And remember, some people might experience an increase in heart rate after watching a cute animal video like the one you saw, perhaps an indication that they were experiencing “kawaii feeling.”
In Wells' study, after watching any one of the five videos—fish, birds, monkeys, people, or a blank screen—all participants had lower heart rates and blood pressure, indications that they were more relaxed (Wells, 2005). This isn’t surprising, as this phase of the experiment was intended to be relaxing, regardless of video content. In fact, Wells cited research by Herbert Benson (1975) that showed that people tend to become more relaxed when they are sitting quietly and comfortably while focusing on something, like the videos in Wells' study and in this activity.
Correct! Participants who watched any of the animal videos—fish, birds, or monkeys—had lower average heart rates and lower average blood pressure as compared with participants who watched either of the control videos—people or a blank screen. Relaxation from watching an animal video was actually protective against the future stress of reading out loud.
Incorrect. Guess again!
Susan Nolan
13.5Consider Alternative Explanations
3
Consider Alternative Explanations
13.5.1From an Experiment to “Real Life”
Deborah Wells’ research findings could be good news for British Airways. During a stressful experience, people who had watched animal videos showed fewer signs of stress—like increased heart rate and blood pressure—than people who watched other videos. We might conclude that Wells’ findings support British Airways’ new programming—that animal videos help people cope with stress on a plane. But is there an alternative explanation?
Every experiment is different in some ways from what goes on outside the lab in the “real world,” such as on an airplane flight. Does this matter? Some differences probably do matter. For example, the lab environment is very controlled, but in “real life” there are always surprises, like turbulence making your flight even more stressful than normal! But other differences probably don’t matter. We might guess that it doesn’t matter whether you watch an animal video on a laptop versus a screen mounted on the headrest in front of you on a plane. What about other differences?
13.5.2Compare the Experiment and the In-Flight Experience
Let’s consider some of the specific differences between the experiment you learned about and someone’s experience watching animal videos on a flight. For each of the differences listed below, explain how it could make a difference in outcome.
The experiment showed the videos before the stressful experience. In the airplane, passengers are watching the videos during the experience.
The stress of flying might be more severe, and therefore harder to alleviate.
The videos in the experiment were described as slow-paced and silent. British Airways’ videos include cats and dogs playing, and are unlikely to be slow-paced. The videos also have sound.
It is possible that fast-paced videos with sound are less relaxing than slower-paced, silent ones.
Scientists ask questions about factors like these after every experiment. It doesn’t mean this isn’t a valuable experiment with something to tell us. It probably is helpful scientific evidence for the British Airways team that created the Paws and Relax channel. But it’s rare that a single study is the “last word” on any research question. A well-done study often leads to more questions. That is why good science involves the replication of experiments—both in the lab, and when possible, out in the world. This is how good science works!
13.5.3The Airplane as Laboratory
If British Airways wanted to test their claim that their new channel reduces stress, they could conduct an experiment on their flights. They could offer passengers travel vouchers or free airport meals to participate, and then randomly assign them to watch either the Paws and Relax channel or a control channel, something without animals.
The airline would need to choose a dependent variable to measure during or after the flight. For example, they might choose to monitor the heart rates of all participants throughout their flight.
If the differences that we discussed earlier—timing of the videos, type of stress, and pacing and sound—aren’t important differences, then the animal videos would reduce stress on the plane as well as in the lab.
But as a good scientist will tell you, there would then be a new question to ask, and another experiment to conduct!
James Peragine/Getty Images
13.6Consider the Source of the Research or Claim
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Consider the Source of the Research or Claim
13.6.1A Company Versus a Journal Article
Thinking like a scientist also involves thinking about the source of information. In this activity, we looked at information from two sources—British Airways and a journal article. British Airways is a company that claims to be using science to develop their new in-flight animal channel. Like most companies, they don’t discuss the research they use in detail, and there’s no expectation that they should. It would be kind of weird if you had to watch a five-minute video explaining the science before you got to see the kitten and puppy videos that you’re excited about.
That shouldn’t stop you, as a good consumer of information, from thinking like a scientist. When a company makes a claim, you can ask the right questions about whether that claim is backed by evidence, just as we did in this activity.
British Airways
13.6.2Science in the News
As we mentioned early in this activity, the British Airways in-flight entertainment manager cited research demonstrating that “watching images of cute animals can actually lower your heart rate and reduce stress levels” (British Airways Media Centre, 2014). It turns out there is some research to back this claim. In a footnote to their news release, British Airways mentions a book by a prominent U.K. psychologist. And in this activity we explored research on this topic that is published in a peer-reviewed journal. Both sources provide details about the research that we can evaluate.
Unfortunately, there isn’t yet a “science badge” that can tell us when news is scientifically backed. When a company makes such a claim, it’s often not true. So when you read news that gives support for a claim by saying a version of “because science says so,” it’s time to think like a scientist and ask what that means. We need to know that there’s solid research, conducted by scientists without a conflict of interest and published in a well-respected, peer-reviewed journal.
The correct answer is D. When we use random assignment, we can assume that, overall, the participants in the different conditions are similar. People with high levels of stress, for example, will tend to end up evenly distributed across all five of the conditions. But if we let people select their own condition, we cannot know that. There might be some characteristic leading people to choose certain conditions. For example, people who chose to watch animal videos may be less susceptible to stress, on average, than people who choose to watch people videos or a blank screen.
The correct answer is D. When we use random assignment, we can assume that, overall, the participants in the different conditions are similar. People with high levels of stress, for example, will tend to end up evenly distributed across all five of the conditions. But if we let people select their own condition, we cannot know that. There might be some characteristic leading people to choose certain conditions. For example, people who chose to watch animal videos may be less susceptible to stress, on average, than people who choose to watch people videos or a blank screen.
The correct answer is C. When we do not use random assignment, we cannot know which factors led to a particular outcome. In this hypothetical case, a decrease in overall stress levels could be due to videos on the Paws and Relax channel, the friendly flight attendants, or even just the passage of time. However, we know a decrease couldn’t result from watching other channels, because in this scenario, the only option was the Paws and Relax channel.
The correct answer is A. Psychological science leads to findings about groups of people rather than about any particular individual. There will always be exceptions to any research findings. But that doesn’t mean that a particular finding is not true in general.
The correct answer is A. Psychological science leads to findings about groups of people rather than about any particular individual. There will always be exceptions to any research findings. But that doesn’t mean that a particular finding is not true in general.
The correct answer is D. Anytime you hear a claim in the news or elsewhere, your first question should be whether there is scientific evidence to back it up. In this case, there is. The newspaper article was actually written by Canadian psychology researchers who had previously reported this research finding in a peer-reviewed article in the journal Computers in Human Behavior (Kushlev & Dunn, 2015).
The correct answer is C. The independent variable is the frequency of email checking—either unlimited or just three times a day. The dependent variable is the stress level.
The correct answer is C. The independent variable is the frequency of email checking—either unlimited or just three times a day. The dependent variable is the stress level.