Cognitive Biases
Our brains take mental shortcuts that sometimes lead us astray. Understanding these biases helps us make better decisions.
Confirmation Bias
What it is: We tend to seek out and remember information that confirms what we already believe, while ignoring contradicting evidence.
People consistently see bias in others while believing they themselves are objective[1].
Anchoring Effect
What it is: The first piece of information we hear disproportionately influences our judgment, even if it's irrelevant.
Anchoring affects our judgments even when we know the anchor is arbitrary[2].
Sunk Cost Fallacy
What it is: We continue investing in something because of what we've already put in, even when it's rational to stop.
The sunk cost effect is driven by emotional reactions to "wasted" investment[3]. Example: Finishing a bad movie because you paid for it.
Dunning-Kruger Effect
What it is: People with limited knowledge tend to overestimate their competence, while experts often underestimate theirs.
Studies show those with least knowledge often have highest confidence[4].
Decision Making
Loss Aversion
We feel losses more intensely than equivalent gains[6]. Losing $100 feels worse than gaining $100 feels good.
Self-Control
The ability to delay gratification varies significantly and develops with age[7]. The famous "marshmallow test" showed children who could wait for two treats often had better outcomes later in life – though recent replications suggest the effect is smaller than originally thought.
Mind and Body
The Placebo Effect
This isn't "just in your head" – placebos can trigger genuine physiological changes. Understanding this helps explain why alternative medicine sometimes "works."
Emotional Regulation
How we manage our emotions affects mental health outcomes[9].
Common strategies:
- Reappraisal – Reframing how you think about a situation (healthier)
- Suppression – Hiding emotions (less effective long-term)
- Avoidance – Avoiding emotional situations (often counterproductive)
Practical Takeaways
- Consider the opposite: When you form an opinion, deliberately look for evidence against it
- Watch for anchors: When negotiating or estimating, be aware of the first number mentioned
- Evaluate sunk costs: Ask "Would I start this now?" rather than "How much have I invested?"
- Question confidence: High certainty isn't proof of correctness – sometimes it's a warning sign
- Acknowledge emotions: Suppressing feelings is usually less effective than understanding and reframing them
References
- Various (2020). Bias in bias recognition: People view others but not themselves as biased. PLOS ONE. [DOI]
- Various (2015). Anchors as Semantic Primes in Value Construction: An EEG Study. PLOS ONE. [DOI]
- Various (2019). The feeling of throwing good money after bad: The role of affective reaction in the sunk-cost effect. PLOS ONE. [DOI]
- Various (2025). Do opinion leaders know more? Knowledge accuracy, self-confidence, and the Dunning-Kruger effect. PLOS ONE. [DOI]
- Various (2020). Decision making biases in the allied health professions: A systematic scoping review. PLOS ONE. [DOI]
- Various (2016). Who Are You More Likely to Help? The Effects of Expected Outcomes on Prosocial Behavior. PLOS ONE. [DOI]
- Various (2021). Waiting for the better reward: Comparison of delay of gratification in children and adults. PLOS ONE. [DOI]
- Various (2015). Different Placebos, Different Mechanisms, Different Outcomes. PLOS ONE. [DOI]
- Various (2020). Psychiatric symptoms and emotion regulation strategies during COVID-19. PLOS ONE. [DOI]