Prediction Error Minimisation

Prediction Error Minimisation

Prediction Error Minimisation (PEM) is a neuroscientific theory of the brain. The theory suggests that the brain’s purpose is to make sense of the world in which the individual finds themselves. It does this by taking in sensory input, combining with prior experience held as memories, and on that basis forms predictions as to what is being experienced.

According to PEM, when we look at a cup, we see colour, texture, shape. Our brain, incredibly quickly, compares this to prior experience, and presents to the mind the label, “cup”. At this point, the individual can interact with the “cup” without needing to pay it any further attention (so long as it continues to function as a cup).

Should further sensory information challenge the prediction a “prediction error” is said to occur. At this point, the brain must reclassify the experience. A common example of this is with optical illusions. Once seen, they cannot be unseen. This is because the new classification is more accurate than the previous one.

PEM argues that the brain’s role is to prevent prediction errors (hence its name).

PEM is mostly applied to external experience - sensation through “exteroception”, that is through the five senses. However, in her book, [How Emotions are Made] (, Lisa Feldman Barrett argues that PEM appies to emotions as well as external experience. That is, sensory experience comes via interoception too - the sensations coming from within the body, whether sensory or emotional in nature.