Meta-analysis of associations between human brain volume and intelligence differences: How strong are they and what do they mean?

@article{Pietschnig2015MetaanalysisOA,
  title={Meta-analysis of associations between human brain volume and intelligence differences: How strong are they and what do they mean?},
  author={Jakob Pietschnig and Lars Penke and Jelte M. Wicherts and Michael Zeiler and Martin Voracek},
  journal={Neuroscience \& Biobehavioral Reviews},
  year={2015},
  volume={57},
  pages={411-432}
}
Positive associations between human intelligence and brain size have been suspected for more than 150 years. Nowadays, modern non-invasive measures of in vivo brain volume (Magnetic Resonance Imaging) make it possible to reliably assess associations with IQ. By means of a systematic review of published studies and unpublished results obtained by personal communications with researchers, we identified 88 studies examining effect sizes of 148 healthy and clinical mixed-sex samples (>8000… 

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