TY - JOUR
T1 - Are Bigger Brains Smarter? Evidence From a Large-Scale Preregistered Study
AU - Nave, Gideon
AU - Jung, Wi Hoon
AU - Karlsson Linnér, Richard
AU - Kable, Joseph W.
AU - Koellinger, Philipp D.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - A positive relationship between brain volume and intelligence has been suspected since the 19th century, and empirical studies seem to support this hypothesis. However, this claim is controversial because of concerns about publication bias and the lack of systematic control for critical confounding factors (e.g., height, population structure). We conducted a preregistered study of the relationship between brain volume and cognitive performance using a new sample of adults from the United Kingdom that is about 70% larger than the combined samples of all previous investigations on this subject (N = 13,608). Our analyses systematically controlled for sex, age, height, socioeconomic status, and population structure, and our analyses were free of publication bias. We found a robust association between total brain volume and fluid intelligence (r =.19), which is consistent with previous findings in the literature after controlling for measurement quality of intelligence in our data. We also found a positive relationship between total brain volume and educational attainment (r =.12). These relationships were mainly driven by gray matter (rather than white matter or fluid volume), and effect sizes were similar for both sexes and across age groups.
AB - A positive relationship between brain volume and intelligence has been suspected since the 19th century, and empirical studies seem to support this hypothesis. However, this claim is controversial because of concerns about publication bias and the lack of systematic control for critical confounding factors (e.g., height, population structure). We conducted a preregistered study of the relationship between brain volume and cognitive performance using a new sample of adults from the United Kingdom that is about 70% larger than the combined samples of all previous investigations on this subject (N = 13,608). Our analyses systematically controlled for sex, age, height, socioeconomic status, and population structure, and our analyses were free of publication bias. We found a robust association between total brain volume and fluid intelligence (r =.19), which is consistent with previous findings in the literature after controlling for measurement quality of intelligence in our data. We also found a positive relationship between total brain volume and educational attainment (r =.12). These relationships were mainly driven by gray matter (rather than white matter or fluid volume), and effect sizes were similar for both sexes and across age groups.
KW - brain volume
KW - educational attainment
KW - intelligence
KW - open data
KW - open materials
KW - preregistered
KW - preregistered analysis
KW - UK Biobank
UR - http://www.scopus.com/inward/record.url?scp=85060353390&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85060353390&partnerID=8YFLogxK
U2 - 10.1177/0956797618808470
DO - 10.1177/0956797618808470
M3 - Article
C2 - 30499747
AN - SCOPUS:85060353390
SN - 0956-7976
VL - 30
SP - 43
EP - 54
JO - Psychological science
JF - Psychological science
IS - 1
ER -