A study published last week in the journal Neuron might put the nail in the coffin on the standard IQ test and could pave the way for better tests to measure intelligence. Researchers from the Brain and Mind Institute in London, Ontario, had more than 100,000 volunteers complete 12 cognitive online tests to assess memory, reasoning, concentration, and planning abilities. The researchers also performed brain scans on 16 study participants to see which circuits of the brain were activated for each of these cognitive abilities.
What they found was that variations in performance on the testing was due to differences in short-term memory, reasoning, and verbal skills. They also found that no one component — such as IQ which measures how well we reason, distinguish relationships, and solve problems — explained all the variations and that distinct circuits of the brain were activated for each of the different cognitive tasks.
Interestingly, the researchers also took surveys of those who took the online test to assess their lifestyle habits and found that age was the most significant predictor of performance, with those in their 60s performing less well on memory and reasoning tests than those in their 20s. Smokers also performed more poorly on short-term memory and verbal tests.