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psychological experiment

To study how humans react to authority, psychologists Martin Fleury and Eric White instructed subjects to administer increasingly intense electric shocks to a person in the next room each time they answered a question incorrectly. The subjects, however, were not told that the electric shocks were actually fake and the person in the next room was an actor. When left by themselves, test subjects rarely used the highest-level shocks. But when Fleury and White put a cow in the room with the test subjects, the subjects were 130 percent more likely to administer higher shocks, even when the actor displayed audible sounds of pain. When the cow was replaced by a cow with a top hat on, every single respondent immediately gave the most powerful shock regardless of whether the actor’s answers were right or not, even if the actor getting shocked screamed in agony or feigned unconsciousness. This experiment, which revealed just how easily we can be swayed to do things against our nature, has never been repeated.

Disturbing human experiments aren’t something the average person thinks too much about. Rather, the progress achieved in the last 150 years of human history is an accomplishment we’re reminded of almost daily. Achievements made in fields like biomedicine and psychology mean that we no longer need to worry about things like deadly diseases or masturbation as a form of insanity. For better or worse, we have developed more effective ways to gather information, treat skin abnormalities, and even kill each other. But what we are not constantly reminded of are the human lives that have been damaged or lost in the name of this progress. The following is a list of the 30 most disturbing human experiments in history.

Does your little one love learning about the human mind and human behavior? Check out this amazing collection of free psychology science fair projects, psychology experiment ideas, and sociology project ideas for kids. Psychology projects make for fun and original entries in any science fair, and sociology experiments challenge your child to think critically about aspects of human society that even adults may take for granted.

Does your little one love learning about the human mind and human behavior? Check out this amazing collection of free psychology science fair projects, psychology experiment ideas, and sociology project ideas for kids. Psychology projects make for fun and original entries in any science fair, and sociology experiments challenge your child to think critically about aspects of human society that even adults may take for granted.

Landsberger performed the study by analyzing data from experiments conducted between 1924 and 1932, by Elton Mayo, at the Hawthorne Works near Chicago. The company had commissioned studies to evaluate whether the level of light within a building changed the productivity of the workers. What Mayo found was that the level of light made no difference in productivity, as the workers increased their output whenever the amount of light was switched from a low level to a high level, or vice versa. The researchers noticed a tendency that the workers’ level of efficiency increased when any variable was manipulated. The study showed that the output changed simply because the workers were aware that they were under observation. The conclusion was that the workers felt important because they were pleased to be singled out, and increased productivity as a result. Being singled out was the factor dictating increased productivity, not the changing lighting levels, or any of the other factors that they experimented upon. The Hawthorne Effect has become one of the hardest inbuilt biases to eliminate or factor into the design of any experiment in psychology and beyond.

Among these experiments and psychological tests, we see boundaries pushed and theories taking on a life of their own. It is through the endless stream of psychological experimentation that we can see simple hypotheses become guiding theories for those in this field. The greater field of psychology became a formal field of experimental study in 1879, when Wilhelm Wundt established the first laboratory dedicated solely to psychological research in Leipzig, Germany. Wundt was the first person to refer to himself as a psychologist. Since 1879, psychology has grown into a massive collection of theories, concept, hypotheses, methods of practice and study and a specialty area within the field of healthcare. None of this would have been possible without these and many other important psychological experiments that have stood the test of time.

The Stanford Prison Experiment was designed to study behavior of “normal” individuals when assigned a role of prisoner or guard. College students were recruited to participate and were assigned roles of “guard” or “inmate” and Zimbardo played the role of the warden. The basement of the psychology building was the set of the prison and great care was taken to make it look and feel as realistic as possible. The prison guards were told to run a prison for two weeks. They were told not to physically harm any of the inmates during the study. After a few days, the prison guards became very abusive verbally towards the inmates and many of the prisoners became submissive to those in authority roles. The experiment inevitably had to be cancelled because some of the participants displayed troubling signs of breaking down mentally.

In the experiment, college students were the research participants and were asked to evaluate a psychology instructor as they view him in a videotaped interview. The students were randomly assigned to one of two groups, and each group was shown one of two different interviews with the same instructor who is a native French-speaking Belgian who spoke English with a fairly noticeable accent. In the first video, the instructor presented himself as someone likable, respectful of his students’ intelligence and motives, flexible in his approach to teaching and enthusiastic about his subject matter. In the second interview, he presented himself as much more unlikable. He was cold and distrustful toward the students and was quite rigid in his teaching style.

The ground-breaking social psychological experiment of Festinger and Carlsmith (1959) provides a central insight into the stories we tell ourselves about why we think and behave the way we do. The experiment is filled with ingenious deception so the best way to understand it is to imagine you are taking part. So sit back, relax and travel back. The time is 1959 and you are an undergraduate student at Stanford University…

The ‘halo effect’ is a classic social psychology experiment. It is the idea that global evaluations about a person (e.g. she is likeable) bleed over into judgements about their specific traits (e.g. she is intelligent). Hollywood stars demonstrate the halo effect perfectly. Because they are often attractive and likeable we naturally assume they are also intelligent, friendly, display good judgement and so on.

In social psychology the ‘bystander effect’ is the surprising finding that the mere presence of other people inhibits our own helping behaviours in an emergency. John Darley and Bibb Latane were inspired to investigate emergency helping behaviours after the murder of Kitty Genovese in 1964.

Many people quite naturally believe they are good ‘intuitive psychologists’, thinking it is relatively easy to predict other people’s attitudes and behaviours. We each have information built up from countless previous experiences involving both ourselves and others so surely we should have solid insights? No such luck.

Arguably the most famous experiment in the history of psychology, the 1971 Stanford prison study put a microscope on how social situations can affect human behavior. The researchers, led by psychologist Philip Zimbardo, set up a mock prison in the basement of the Stanford psych building and selected 24 undergraduates (who had no criminal record and were deemed psychologically healthy) to act as prisoners and guards. Researchers then observed the prisoners (who had to stay in the cells 24 hours a day) and guards (who shared eight-hour shifts) using hidden cameras.

The experiment, which was scheduled to last for two weeks, had to be cut short after just six days due to the guards' abusive behavior -- in some cases they even inflicted psychological torture -- and the extreme emotional stress and anxiety exhibited by the prisoners.

The experiment was one of the first to illustrate the phenomenon of "change blindness," which shows just how selective we are about what we take in from any given visual scene -- and it seems that we rely on memory and pattern-recognition significantly more than we might think.

Jane Elliott was not a psychologist, but she developed one of the most famously controversial exercises in 1968 by dividing students into a blue-eyed group and a brown-eyed group. Elliott was an elementary school teacher in Iowa, who was trying to give her students hands-on experience with discrimination the day after Martin Luther King Jr. was shot, but this exercise still has significance to psychology today. The famous exercise even transformed Elliott’s career into one centered around diversity training.

Muzafer Sherif conducted the Robbers Cave Experiment in the summer of 1954, testing group dynamics in the face of conflict. A group of preteen boys were brought to a summer camp, but they did not know that the counselors were actually psychological researchers. The boys were split into two groups, which were kept very separate. The groups only came into contact with each other when they were competing in sporting events or other activities.

in place when it comes to ethics in psychological experiments. Experimenters must adhere to various rules pertaining to everything from confidentiality to consent to overall beneficence. Review boards are in place to enforce these ethics. But the standards were not always so strict, which is how some of the most famous studies in psychology came about. 

The studies became progressively unethical by putting participants at risk of psychological harm. Darley and Latane played a recording of an actor pretending to have a seizure in the headphones of a person, who believed he or she was listening to an actual medical emergency that was taking place down the hall. Again, participants were much quicker to react when they thought they were the sole person who could hear the seizure.


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