Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
As the Department Chair of Psychology at Monmouth University, I teach primarily upper level undergraduate students who are interested in Experimental Methods. These classes don’t have the same inherent appeal to students. This JoVE Psychology collection will help students vicariously watch the experiments being performed from start to finish, allowing them to gain exposure to over a dozen topics that they may not experience otherwise. Importantly, the videos provide a context for seeing the experiments embedded in their natural states—in the actual research process.
A few projects in this Science Education collection stand out. First, I consider the Ethics in Psychological Research video to be very useful in teaching, as it demonstrates how sensitive topics, such as interpersonal violence, can be studied in creative ways. Furthermore, students learn better with topics that they care about and can conceptualize in their personal lives. For example, Observational Research delves into the factors that go into homesickness, going beyond questionnaires and examining the relationship to what individuals actually leave around in their rooms. This design allows the researcher to curiously discover conclusions that students may not be fully aware of themselves.
Being an instructor and textbook author of research methods, I am keenly aware of the relative lack of quality resources that are available to teach Experimental Psychology well. These JoVE videos will help bring the material to life for instructors and particularly for students who do not necessarily get the opportunity to complete their own research projects.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
In any experiment researchers have the challenge of creating experiences for participants that are consistent (i.e., reliable) and authentic (i.e., valid). Yet there are many ways to manipulate any one variable. For example, if you want participants to feel sad, you can have them think of their own sad memory, watch a sad video, or read a sad story.
Researchers must find the best way to operationalize a psychological construct in order to produce the most effective manipulation possible. Often, before running the main study, researchers will pilot test (i.e., try out) their manipulations to check their effectiveness.
This video demonstrates how to operationalize the same independent variable (acute stress) in three different ways. Specifically, this study seeks to identify the best sound (static, ticking clock, or crying baby) to play during a difficult task (solving complex math problems) to optimally manipulate stress.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented and the margin of error accompanied by studying human behavior is sufficiently accounted for. In this video, we demonstrate this experiment using just three participants, one for each condition. However, as represented in the results, we used a total of 120 (40 for each condition) participants to reach the experiment’s conclusions reflected in the Results section.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
Clinical research focuses on the efficacy of treatments for addressing disorders and illnesses. A challenge with this type of research is that participants often have pre-existing beliefs about the treatment, particularly expectations that the treatment will work.
Though it has been practiced around the world for centuries, yoga is a relatively recent fitness craze in the United States with a wide range of alleged benefits, including the belief that it improves one’s creativity. However, it is not always clear whether yoga is actually creating the benefits, like improved creativity, or the yoga practitioner’s expectations are really the cause.
This video demonstrates a two-group design that examines whether a person who believes he or she is doing yoga (but in reality is not) experiences similar benefits to a person who actually does yoga. Specifically, this study looks at whether there is a placebo effect such that merely believing you are doing yoga benefits creativity.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented and the margin of error accompanied by studying human behavior is sufficiently accounted for. Further, human participants for research like this are often readily available and the experiment is quick and inexpensive to replicate. In this video we demonstrate this experiment using just one participant. However, as represented in the results, we used a total of 80 (40 for each condition) participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
In an ideal world researchers would conduct their studies in real world settings where behaviors naturally happen. For example, if you want to see what influences individuals’ voting behavior, it would be best to watch them vote. However, research in these settings is not always ethical or even practical. Further, a researcher may want more control over the setting to better pinpoint the exact variables that are influencing an outcome.
When researchers need to conduct studies in a lab, they try to optimize mundane realism, which means that they do everything they can to make the lab feel like a real-life experience. This video demonstrates a two-group design that examines how researchers use mundane realism in a lab to determine whether positive restaurant reviews are connected to diners’ level of tipping.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented and the margin of error accompanied by studying human behavior is sufficiently accounted for.
In this video, we demonstrate this experiment using just two participants, one for each condition. However, as represented in the results, we used a total of 200 (100 for each condition) participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
A within-subjects, or repeated-measures, design is an experimental design where all the participants receive every level of the treatment, i.e., every independent variable. For example, in a candy taste test, the researcher would want every participant to taste and rate each type of candy.
This video demonstrates a within-subjects experiment (i.e., one where there is an independent variable with several variations or levels) that examines how different motivational messages (e.g., hard work, self-affirmation, outcomes, and positive affect) influence willingness to exert physical effort. As a within-subjects design, the participant will read each of the four types of motivational messages and then lift weights to measure physical effort. By providing an overview of how a researcher conducts a repeated-measures experiment, this video allows viewers to see how to address order effects through counterbalancing, which involves a systematic approach to making sure all possible orders of the conditions occur in the study.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented and the margin of error accompanied by studying human behavior is sufficiently addressed. In this video, we demonstrate this experiment using just one participant. However, as represented in the results, we used a total of 72 participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
When a researcher finds an interesting topic to study such as aggression, the goal is often to study it in a way that is as true to life as possible. However, researchers must act in an ethical manner. To do this, they must balance their research goals with the best interests of the participants. Ethics often enter into the planning process when researchers identify all of the ways they can manipulate or measure a variable, but then make their final decision based on how they should manipulate or measure a variable.
After receiving a poor grade on a test or paper, a college student may appear to take it out on (i.e., act in an aggressive manner toward) their roommates by being mean or nasty, screaming, throwing things, or even becoming physically violent. Aggression is an important human behavior to study and understand due to the implications it has for interpersonal violence. However, for safety reasons, a study cannot expose participants to the risk that serious types of violence presents. As a result, researchers must identify similar but benign behaviors that can help us understand more aggressive behaviors without harming participants.
This video uses a two-group experiment to see if people really take out their anger on others even though the others are not responsible for the original problem. Specifically, it examines whether negative feedback leads to aggression while considering key ethical issues such as harm to participants, costs vs. benefits, informed consent, and debriefing.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to better ensure that the population under study is better represented, i.e., the margin of error accompanied by studying human behavior is sufficiently accounted for. In this video we demonstrate this experiment using just two participants, one being the evaluator. However, as represented in the results, we used a total of 245 participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
In order to study something scientifically, a researcher needs to determine a way to quantify it. However, psychological constructs can be challenging to measure and quantify. This video examines reliability in the context of content analysis.
A recent study in the journal Pediatrics reported that 4-year-olds who watched a fast-paced cartoon had worse performance on cognitive tasks, such as following rules in a game, listening to direction from an adult, and delaying gratification, compared to other children who watched a slower paced cartoon.1 In addition to the pace of the cartoon, the content of the cartoon may also have deleterious effects on its young viewers.
This video uses a simple two-group design, to exemplify the issue of reliability, in examining the question of whether the cartoon SpongeBob SquarePants has more inappropriate content than does the cartoon Caillou.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
Research studies come into being when a researcher speculates about human thought, emotions, or behavior, and has a theory that offers a potential explanation. Often the researcher’s theory is firmly situated in everyday common experiences that may not naturally lend themselves to direct empirical study.
For example, researchers speculated that perception of a person on Facebook is influenced by the appearances and comments of the person’s Facebook friends.1 It is difficult to test this theory using real-life Facebook profiles. Instead, researchers must use their creativity to design a study—in this case, using fake profiles that look highly realistic—to test their theory.
This video demonstrates how researchers test a central tenet of a popular social psychology theory. Specifically, this video shows a test of whether engaging in a self-expanding activity leads a person to feel a greater sense of self-efficacy.2
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented, i.e., the margin of error accompanied by studying human behavior is sufficiently accounted for. In this video, we demonstrate this experiment using just 2 participants, one for each condition. However, as represented in the results, we used a total of 100 (50 for each condition) participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
If you want to know how someone thinks or feels, you can ask that person questions. Another approach is to observe how the person is acting or look for indicators of how they acted in the past. While observations may seem revealing, it isn’t always easy to know if they are truly accurate. For instance, you may see a person smiling and assume they are happy, when in reality they are annoyed and merely being polite.
The purpose of science is to move beyond an individual’s own views of the self because they are inherently skewed by that individual’s expectations, previous experience, personal biases, motivations, emotions, etc. While a person may have unique insight into one’s self, these insight may not accurately represent reality. Put more simply, what a person says, does not always match up well with what they actually do. For this reason, researchers should incorporate a variety of measures (e.g., asking participants to report how they feel, but also observing actual behavior) in order to more accurately capture how the person truly feels.
This video demonstrates a correlational design where researchers measure students’ homesickness in two distinct ways: (1) a homesickness scale, and (2) by observing how the student has decorated his or her dorm room.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to ensure that the population under study is better represented, i.e., the margin of error accompanied by studying human behavior is sufficiently accounted for. In this video, we demonstrate this experiment using just one participant. However, as represented in the results, we used a total of 63 participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
In any experiment, the researcher attempts to manipulate participants in one group to have different thoughts, experiences, or feelings than the other groups in the study. Some manipulations are overt, while others can be quite subtle. Embodiment is a growing research area focused on the theory that subtle physical experiences can unconsciously influence a person’s thoughts. For example if a person physically smiles, it often leads to elevated mood. That is, the physical experience of smiling changes the way a person feels.
This video uses a two-group experiment to see if the physical sensation of weight will lead people to be stricter by giving harsher forms of discipline to fellow students who violated campus policies.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
One of the challenges in measuring an experimental variable is identifying the technique that will produce the more accurate measurement. The most common way to measure a dependent variable is self-report—asking the participant to describe his/her feelings, thoughts, or behaviors. Yet, people may not be honest. To truly know something about a participant, it may be necessary to see what they actually do in a situation.
This video uses a multi-group experiment to see if feeling close to others results in more favorable attitudes toward environmental consciousness measured both by self-report and behavioral observation.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to better ensure that the population under study is better represented, i.e., the margin of error accompanied by studying human behavior is sufficiently accounted for. In this video, we demonstrate this experiment using just one participant. However, as represented in the results, we used a total of 186 participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
When orchestrating an experiment, it is important that the experience elicits the most natural reactions from the participants as possible. Researchers accomplish much of this through their creation of the experimental settings.
Many research projects focus on interactions between two or more people. In these situations the environment or setting must often be less natural; often only one person can be a true participant and others in the study need to be “confederates,” that is, allegedly unbiased participants whom, in actuality, act according to the researcher’s directions.
This video uses a two-group experiment to see if participants are more likely to imitate a person with more power versus similar power compared to the participant. The video also highlights the use of research confederates.
Psychological studies often use higher sample sizes than studies in other sciences. A large number of participants helps to better ensure that the population under study is better represented, i.e. the margin of error accompanied by studying human behavior is sufficiently accounted for. Further, human participants for research like this are often readily available and the experiment is quick and inexpensive to replicate so we want to use as many participants as possible. In this video we demonstrate this experiment using just one participant. However, as represented in the results, we used a total of 156 participants to reach the experiment’s conclusions.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
A two-group design is the simplest way to establish a cause-effect relationship between two variables. This video demonstrates a simple experiment (two-group design). In providing an overview of how a researcher conducts a simple experiment (two-group design), this video shows viewers the process of turning ideas into testable ideas and forming hypothesis, the identification and effect of experiment variables, the formation of experimental conditions and controls, the process of conducting the study, the collection of results, and the consideration their implications. This research technique is demonstration in the context of answering the research question: “How does physiological arousal/excitement influence perceived attraction?”
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
A multi-group design is an experimental design that has 3 or more conditions/groups of the same independent variable. This video demonstrates a multi-group experiment that examines how different interethnic ideologies (multiculturalism and color-blind) influence feelings about diversity and actions toward and out-group member. In providing an overview of how a researcher conducts a multi-group experiment, this video shows viewers how to distinguish levels in variables, common types of conditions/groups to use (including placebo and empty-control conditions/groups), the process of conducting the study, the collection of results, and the consideration of their implications.
Experimental Psychology
Source: Laboratories of Gary Lewandowski, Dave Strohmetz, and Natalie Ciarocco—Monmouth University
A factorial design is a common type of experiment where there are two or more independent variables. This video demonstrates a 2 x 2 factorial design used to explore how self-awareness and self-esteem may influence the ability to decipher nonverbal signals. This video leads students through the basics of a factorial design including, the nature of a factorial design and what distinguishes it from other designs, the benefits of factorial design, the importance and nature of interactions, main effect and interaction hypotheses, and how to conduct a factorial experiment.
Experimental Psychology
