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I have been teaching psychology for more than 40 years, and there are common misconceptions about psychological terms and definitions. Here are 10 of the most frequent I have encountered in my teaching career.
1. Confusing negative reinforcement and punishment.
Negative reinforcement occurs with the withdrawal of some aversive stimulus following the display of a desired behavior. Punishment targets undesired behaviors with an aversive stimulus to stop the unwanted behavior. An episode of The Big Bang Theory had Sheldon punishing Penny with a spray bottle, but he referred to it as “negative reinforcement.” A show about scientists should know better.
2. Confusing negative reinforcement and positive reinforcement.
All too often, clearly negative reinforcement is twisted around to be interpreted as positive reinforcement. I use the example of letting class out early if the discussion is positive. Sadly, leaving early is not a reward, but a chance to “escape” a situation that students don’t want to be in any longer than they have to….
3. Believing that schizophrenia is the same as multiple personalities.
You see this all the time. Schizophrenia involves symptoms such as disordered thinking and psychosis, which is separate from multiple personalities, or what is called "dissociative identity disorder."
4. Believing that the brain works like a computer in storing memories.
Research on memory tells us that we store reconstructions of our experiences. There is no sort of “video” of our past experiences stored in our brains.
5. Assuming that a correlation implies causality.
This is all too common, particularly in media reports of psychological studies. Just because two variables are correlated doesn’t imply that one caused the other. The cause could be the other way around, or a “third” variable (or more) could cause them both to change systematically.
6. Believing psychology is all common sense.
Everyone sort of believes that they are an amateur psychologist. This makes sense, because there is so much “folk wisdom” that we are taught as we grow up. But there are usually two competing versions of folk wisdom (“Birds of a feather flock together” versus “opposites attract”). Psychology strives to test folk wisdom.
7. Assuming our personalities can’t change.
Although personality is deeply seated in each of us, it is malleable and subject to change.
8. Believing polygraphs are accurate in detecting lies.
The validity (accuracy) and reliability (trustworthiness) of lie detectors that assess physiological reactions while lying or truth-telling has been called into question. The problem is false positives — people are telling the truth, but the polygraph reading says that they are lying. Liar: not a label anyone wants.
9. Thinking employment and IQ tests are inherently biased.
A commonly held misconception. Early tests of these sorts were culturally biased toward the majority culture (White, more affluent). Throughout the years, such tests have been refined to remove cultural bias.
10. Assuming we learn better with our preferred learning style.
Research on learning suggests that certain learning strategies are superior to others (e.g., spaced learning for performance on your psychology test, as opposed to “massed” learning — what is called “cramming” for an exam). Controlling for this, different learning styles don’t matter much.
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