25 Curiosities

The curious stories we tell about the human mind—and what the research actually says.

Some psychological legends have a tiny seed of truth. The interesting part is discovering where the seed ends and the story begins.

1. Do we use only 10% of our brains? No. Different regions work harder at different moments, which is why a brain image may highlight only a few of them. The unhighlighted regions are not waiting to be switched on for superpowers (Association for Psychological Science [APS], 2018a).

1. Are there creative “right-brained” people and logical “left-brained” people? The hemispheres do have some specialized functions, but they work together. Your personality cannot be sorted into one half of your head (Corballis, 2014).

1. Must a visual learner see pictures to learn well? People have preferences, but matching lessons to a supposed visual, auditory, or hands-on type has not reliably improved learning. A useful picture helps when the subject calls for one (APS, 2022).

1. Does birthday cake make children hyperactive? A birthday party supplies friends, games, excitement, and cake. The simple claim that sugar itself causes the behavior has not held up well in controlled research (APS, 2018b).

1. Will Mozart make a baby smarter? Music can change mood or alertness. It has not been shown to turn infants into geniuses or permanently raise intelligence (APS, 2018c).

1. Does a full moon make people behave strangely? Researchers have not found a reliable surge in psychiatric admissions or crisis calls at the full moon. A dramatic night under a bright moon is easier to remember than an ordinary one (APS, 2018d; Byrnes & Kelly, 1992).

1. Is the oldest child born to lead and the youngest born to rebel? Children may occupy recognizable roles in a family. Across large samples, birth order has shown little power to predict broad adult personality traits (Rohrer et al., 2015).

1. Why can siblings raised together turn out so differently? They do not live identical childhoods. Each has different peers, experiences, and interactions with the family; each also brings a different temperament to those encounters (APS, 2018c).

1. Should you punch a pillow to release anger? It may feel as if anger is leaving your body, but activities that raise arousal have not proved effective overall at reducing it. Calming activities perform better (Kjærvik & Bushman, 2024).

1. Must grief travel through five stages? People may feel anger, sadness, disbelief, relief, or several things at once. There is no required sequence and no failed-grief diagnosis for missing a stage (APS, 2022b).

1. Does avoiding eye contact expose a liar? No single gesture reliably translates into “lying.” Eye contact changes for many reasons, including discomfort and context (Patterson et al., 2023).

1. Can a lie detector detect a lie? A polygraph measures physiological responses, not truth itself. The challenge is deciding what caused the response (Saxe, 1991).

1. Is an eyewitness’s memory a video recording? Memory is reconstructed. A witness can be entirely sincere yet mistake a detail, especially after later information becomes mixed with the original experience (APS, 2018e).

1. Does a confident witness have to be correct? The first confidence judgment, collected promptly under fair conditions, can be informative. Later confidence may change after feedback or repeated questioning (Wixted & Wells, 2017).

1. Can hypnosis recover a perfectly preserved childhood scene? Hypnosis can increase the number of recollections a person reports—and also increase false recollections and confidence in them (Kihlstrom, 1997).

1. If a traumatic memory emerges years later, is its vividness proof? No. Real experiences can be forgotten or remembered imperfectly, and a vivid recollection can also contain errors. Independent evidence matters more than how certain the scene feels (APS, 2018f; Kihlstrom, 1997).

1. Does schizophrenia mean “split personality”? No. Schizophrenia and dissociative identity disorder are different conditions; the similar-sounding popular descriptions have confused people for decades (American Psychological Association, 2022).

1. Will a crowd always ignore an emergency? Crowds can sometimes reduce an individual’s likelihood of helping, but the effect changes with the situation. When danger is clear, other people may also provide support (Fischer et al., 2011).

1. Will a brain-training app make you smarter in every part of life? Repeated puzzles can make you better at those puzzles. Broad improvement in intelligence or everyday functioning is a much bigger claim and has much weaker support (APS, 2018g).

1. Can a hidden message in a movie control what you buy? Information outside awareness can have limited effects in some circumstances. That is far from the legend of a secret message that takes command of someone’s choices (APS, 2019).

1. Does a habit take exactly 21 days? There is no magic deadline. One review found substantial differences across behaviors and people; reaching automaticity often takes considerably longer (Singh et al., 2024).

1. Is personality set in stone at 30? Personality has continuity, but it continues to change across adult life. Being recognizable to old friends does not mean being unchanged (Bleidorn et al., 2022).

1. Must someone recount a frightening event immediately to avoid PTSD? Being safe and supported matters. Requiring everyone to go through a one-session psychological debriefing right away has not been shown to prevent PTSD (Agorastos et al., 2011).

1. Does the adult brain stop changing? No. Adult learning and experience can alter brain connections and white matter pathways. Change remains possible even though the brain does not change in every way at every age (Sampaio-Baptista & Johansen-Berg, 2017).

1. Can you read a stranger like a body-language dictionary? Crossed arms, facial expressions, and personal space have meanings that shift with the person and situation. There is no dependable codebook that translates one gesture into one hidden thought (Patterson et al., 2023).

The point of curiosity is not to replace an old certainty with a new one. It is to look a little closer when an explanation sounds too neat.

References

American Psychological Association. (2022). What is dissociative identity disorder? https://www.apa.org/news/podcasts/speaking-of-psychology/dissociative-identity-disorder.html

Association for Psychological Science. (2018a). Using just 10% of your brain? Think again. https://www.psychologicalscience.org/news/using-just-10-of-your-brain-think-again.html

Association for Psychological Science. (2018b). Myth: Too much sugar causes hyperactivity in children. https://www.psychologicalscience.org/uncategorized/myth-too-much-sugar-causes-hyperactivity-in-children.html

Association for Psychological Science. (2018c). Myth: Children raised in similar ways have similar personalities. https://www.psychologicalscience.org/uncategorized/myth-children-raised-in-similar-ways-have-similar-personalities.html

Association for Psychological Science. (2018d). Overturning myths in introductory psychology. https://www.psychologicalscience.org/observer/overturning-myths-in-introductory-psychology

Association for Psychological Science. (2018e). Myth: Eyewitness testimony is the best kind of evidence. https://www.psychologicalscience.org/uncategorized/myth-eyewitness-testimony-is-the-best-kind-of-evidence.html

Association for Psychological Science. (2018f). Myth: Traumatic memories are often repressed and later recovered. https://www.psychologicalscience.org/uncategorized/myth-traumatic-memories-are-often-repressed-and-later-recovered.html

Association for Psychological Science. (2018g). Myth: Brain training will make you smarter. https://www.psychologicalscience.org/uncategorized/myth-brain-training-will-make-you-smarter.html

Association for Psychological Science. (2019). Myth: Subliminal messages can change your behavior. https://www.psychologicalscience.org/uncategorized/myth-you-can-be-influenced-by-things-outside-your-awareness.html

Association for Psychological Science. (2022). Debunking four common myths of psychological science. https://www.psychologicalscience.org/news/2022-utc-debunking-myths.html

Association for Psychological Science. (2022b). The grieving brain. https://www.psychologicalscience.org/news/2022-utc-the-grieving-brain.html

Bleidorn, W., et al. (2022). Personality stability and change: A meta-analysis of longitudinal studies. https://pubmed.ncbi.nlm.nih.gov/35834197/

Byrnes, G., & Kelly, I. W. (1992). Crisis calls and lunar cycles: A twenty-year review. https://pubmed.ncbi.nlm.nih.gov/1454923/

Corballis, M. C. (2014). Left brain, right brain: Facts and fantasies. https://pmc.ncbi.nlm.nih.gov/articles/PMC3897366/

Fischer, P., et al. (2011). The bystander effect: A meta-analytic review on bystander intervention in dangerous and non-dangerous emergencies. Psychological Bulletin, 137(4), 517–537. https://doi.org/10.1037/a0023304

Agorastos, A., Marmar, C. R., & Otte, C. (2011). Immediate and early behavioral interventions for the prevention of acute and posttraumatic stress disorder. https://pubmed.ncbi.nlm.nih.gov/21941180/

Patterson, M. L., Fridlund, A. J., & Crivelli, C. (2023). Four misconceptions about nonverbal communication. https://www.psychologicalscience.org/journals/perspectives/17456916221148142/

Saxe, L. (1991). Science and the CQT polygraph: A theoretical critique. https://pubmed.ncbi.nlm.nih.gov/1954162/

Kihlstrom, J. F. (1997). Hypnosis, memory and amnesia. https://pubmed.ncbi.nlm.nih.gov/9415925/

Kjærvik, S. L., & Bushman, B. J. (2024). A meta-analytic review of anger management activities that increase or decrease arousal: What fuels or douses rage? Clinical Psychology Review, 109, 102414. https://doi.org/10.1016/j.cpr.2024.102414

Rohrer, J. M., Egloff, B., & Schmukle, S. C. (2015). Examining the effects of birth order on personality. https://pubmed.ncbi.nlm.nih.gov/26483461/

Sampaio-Baptista, C., & Johansen-Berg, H. (2017). White matter plasticity in the adult brain. https://pmc.ncbi.nlm.nih.gov/articles/PMC5766826/

Singh, B., Murphy, A., Maher, C., & Smith, A. E. (2024). Time to form a habit: A systematic review and meta-analysis of health behaviour habit formation and its determinants. Healthcare, 12(23), 2488. https://doi.org/10.3390/healthcare12232488

Wixted, J. T., & Wells, G. L. (2017). The relationship between eyewitness confidence and identification accuracy: A new synthesis. https://pubmed.ncbi.nlm.nih.gov/28395650/