There is a previous notion that stereotypes people with bigger brains to be far way smarter than those with smaller brains. Well, this may be due to what people know about the early human ancestors to include "Lucy" who had quite a small brain in her existence. But after this new research, it may now be better to erase that presumption.
A team of researchers from Austria, the Netherlands, and Germany conducted a meta-analysis of human brain to see if the size correlates with intelligence. A review of 88 studies, comprising more than 8,000 participants, reported that there was only a weak association between the two, enough to believe that brain size does not matter that much.
The observed relationship just confers brain volume a minor role. Even men cannot be said far more advanced than women in terms of cognitive function although generally, they have larger brains than the latter.
"Brain structure and integrity appear to be more important as a biological foundation of IQ, whilst brain size works as one of many compensatory mechanisms of cognitive functions," says lead researcher Jakob Pietschnig of the Institute of Applied Psychology of the University of Vienna, as quoted by ScienceDaily.
The importance of brain structure can also be depicted in other species, in which certain animals, like sperm whales, despite having large brains do not show significantly advanced mental function as compared to others. Moreover, humans who also belong to the animal kingdom, despite being the most intelligent among all organisms, do not have the biggest brains relative to body size.
Apparently, what caused scientists before to believe this concept is what the researchers identified as publication bias. More of strong and positive correlations were reported much frequently in the literature, while those that show less or no relationship were omitted so often in reports. With that, it can be noted that the positive association of brain size with IQ was just overestimated in the literature study authors write.
Nevertheless, the recent review amends the previous conclusions of the whole research and that brain size cannot be a measure of intelligence, regardless of person's sex and age.
The study appears in the journal Neuroscience and Behavioral Reviews.