Larger brain size doesn’t guarantee higher IQ

Much more decisive on the level of intelligence displayed by contrast “the layout of the cortex, midbrain-or midbrain, and cerebellum and the right connection of the white matter and gray matter, much more important than the size of the cerebral mass itself, “he said”.

The findings are based on data from over 8,000 participants.

An worldwide research team, led by Jakob Pietschnig, Michael Zeiler, and Martin Voracek of the University of Vienna, have revealed that – contrary to the age-long belief that a larger brain means higher IQ potential – brain size has a positive relation to brain power, but does not guarantee a high IQ.

According to the findings of the study, scientists have so far “overestimated” the supposed link between brain size and intellectual performance of human beings, said Wednesday Pietschnig Jacob, a researcher in cognitive science at the University of Vienna. They were joined for the study by Lars Penke from the University of Göttingen and Jelte Wicherts from Tilburg University; they conducted a meta-analysis of the relationship that exists between in-vivo brain volume and IQ.

Men may have larger brains than women but that does not make them more intelligent than the members of the fair sex, says a new study that found a very weak association between brain size and IQ.

“While it is tempting to interpret this association in the context of human cognitive evolution and species differences in brain size and cognitive ability, we show that it is not warranted to interpret brain size as an isomorphic proxy of human intelligence differences”, the researchers conclude in Neuroscience and Behavioural Reviews.

They noted that the importance of brain structure compared to brain volume becomes already evident when comparing different species.

Their conclusion is supported by the fact that men consistently have higher brain volumes than women, but that there’s no significant difference between the sexes when it comes to IQ tests. Another example is individuals with megalencephaly syndrome (enlarged brain volume) who typically show lower IQ test performance than the average population.

Previous studies have suggested that their size could be used as a standard assessment, indicating those at increased risk for the development of Alzheimer’s disease.

A total of 34 were diagnosed with Alzheimer’s disease and 82 had ‘amnestic mild cognitive impairment, ‘ which can be a precursor to Alzheimer’s disease. Instead, it’s the structure of your brain that seems play a larger role in determining how smart you are.

He added: ‘We want to detect the earliest signs of dementia and this link between the performance on standard clinical measures of memory and changes in the hippocampus could be another hallmark sign of Alzheimer’s disease’.