Cognitive Biases in Decision-Making
Every decision we make is filtered through our prior experiences, beliefs, and expectations. Cognitive biases are systematic errors in thinking that distort how we process information and reach conclusions. They matter not just in everyday life but in high-stakes professional settings too.
The tendency to seek out, notice, and remember information that supports an existing belief, while overlooking or discounting evidence that contradicts it.
Confirmation bias shapes what we pay attention to. If you have already formed a negative impression of someone, you are more likely to register the moments they behave badly than the moments they are considerate. The same applies to professional judgements.
Mendel et al. (2011) investigated whether mental health professionals are susceptible to confirmation bias.
Seventy-five psychiatrists and seventy-five medical students completed a clinical decision task in which they either searched for confirming evidence, disconfirming evidence, or balanced information.
Those who searched only for confirming evidence were more likely to stick with an incorrect diagnosis and, in some cases, recommended inappropriate treatment.
Around 25% of medical students and 13% of psychiatrists showed this pattern. The finding is significant because it links a cognitive bias directly to real-world harm in a professional context.
The percentages in Mendel et al. (2011) are worth thinking about critically. A majority of participants did not show confirmation bias, which suggests the effect is not universal.
The study does, however, demonstrate that bias can operate even in trained, analytical thinkers, which reinforces its relevance.
This connects directly to the concept of responsibility: if a cognitive bias can distort a clinician's diagnosis, understanding and correcting for it becomes an ethical obligation, not just an academic exercise.
Classical Conditioning
Classical conditioning is one of the earliest and most influential accounts of how learning happens. It emerged from the work of Ivan Pavlov and John Watson in the early twentieth century, during the rise of behaviourism. Behaviourists argued that behaviour is determined by environmental experience rather than internal mental states, and that psychology should focus on what can be directly observed.
A form of learning in which a neutral stimulus becomes associated with an unconditioned stimulus through repeated pairing, eventually producing a conditioned response on its own.
The core terminology is worth learning precisely:
- Unconditioned Stimulus (UCS): A stimulus that automatically triggers a response without any prior learning (e.g. food causing salivation).
- Unconditioned Response (UCR): The automatic, unlearned response to the UCS.
- Neutral Stimulus (NS): A stimulus that initially produces no relevant response.
- Conditioned Stimulus (CS): A formerly neutral stimulus that, after repeated pairing with the UCS, produces a response on its own.
- Conditioned Response (CR): The learned response to the conditioned stimulus, which mirrors the original unconditioned response.
Pavlov demonstrated this by repeatedly ringing a bell just before presenting food to a dog. Over time, the bell alone caused the dog to salivate. The food was the UCS, salivation was the UCR (which became the CR), and the bell moved from a neutral stimulus to a conditioned stimulus.
Advertising uses classical conditioning extensively.
If a celebrity athlete is associated with achievement and excellence, pairing that athlete with a soft drink brand in repeated advertisements may transfer those positive associations to the product.
Consumers begin to feel something about the brand without consciously reasoning about it.
Classical conditioning illustrates how change in behaviour can occur without conscious awareness or deliberate effort. Learning happens through association, not intention.