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Tests > Odd One Out

Odd One Out

Odd One Out assesses deductive reasoning, which is the core cognitive ability to apply rules to information in order to arrive at a logical conclusion. Odd One Out requires reasoning about the features of several shapes to deduce the one shape that does not fit in with the rest.

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How to take the Odd One Out Test

Nine sets of shapes appear on the screen, different from each other in color, shape, and number. The user must pay close attention to how the shapes differ from each other, and point out the one shape that is most different from the rest. In some cases, like when there is only one red shape, the answer is obvious. However, the test gets more difficult with each correct answer, and harder puzzles require comparing several different features at the same time.

The history of Odd One Out

Odd One Out is a modern version of classical tests of fluid intelligence, often used as part of IQ tests. When patients are using their deductive reasoning abilities, their brains show a characteristic pattern of activity in the back and outer surfaces of the frontal lobes, at the intersection of the two hemispheres, and in the middle of the parietal lobe at the back and top of the brain. Damage to these regions impairs reasoning abilities, with more damage leading to more impairment.

Odd One Out in
the real world

Deductive reasoning tasks like Odd One Out are common in classic intelligence tests, and are analogous to many real-world situations. Every time you figure out what is true based on a set of facts, you are using deductive reasoning. Doing well at Odd One Out requires a healthy brain, and cardiovascular fitness has been linked with performance. However, Odd One Out may be a bit more resilient to short-term disruptions, like getting less sleep, compared to other tests.