N-acetylaspartate levels of left frontal cortex are associated with verbal intelligence in women but not in men: a proton magnetic resonance spectroscopy study

doi:10.1016/j.neuroscience.2003.11.008

Neuroscience

Volume 123, Issue 4, 2004, Pages 1053-1058

https://doi.org/10.1016/j.neuroscience.2003.11.008 Get rights and content

Abstract

The left frontal cortex plays an important role in executive function and complex language processing inclusive of spoken language. The purpose of this work was to assess metabolite levels in the left and right prefrontal cortex and left anterior cingulum by proton magnetic resonance spectroscopy and relate results to verbal intelligence (Wechsler Adult Intelligence Scale revised) in a sample of college-educated healthy volunteers (dorsolateral prefrontal cortex [DLPFC]: n=52, 23 females, and left anterior cingulum: n=62, 22 females; age range: 20–75 years). In women only, N-acetylaspartate in the DLPFC and in the left anterior cingulate cortex was positively correlated with vocabulary scores. Our data support the hypothesis of existing gender differences regarding the involvement of the left frontal cortex in verbal processing as reflected in different correlations of specific metabolites with verbal scores.

Section snippets

Study population

Sixty-two subjects aged between 20 and 75 years (Table 1) were enrolled in this study following a standardized interview to rule out any psychiatric or neurological condition (Hiller et al., 2000). There were no differences in age distributions in the group of older subjects >50 years (females: 61.1±1.5 years (n=8); males: 60.6±2.5 years (n=11); t-test; T=0.148; P=0.884), indicating that our results are not influenced by a different age distribution of one gender in older subjects. Almost all

Gender and age effects on metabolites

NAA and Cr-levels were lower in older subjects, even though that did not reach statistical significance. No age dependencies on metabolites were found when analyzing females and males separately.

Cho levels were higher in men than in women in both the left (t-test; T=−1.95, df=53, P=0.057), the right (t-test; T=−2.16, df=53, P=0.040) DLPFC and the left ACC (t-test; T=−1.97, df=62, P=0.053). This difference is only a trend and not significant if the P-level of P<0.0094 was applied. Means and

Discussion

The striking finding was a correlation between higher vocabulary scores, a measure of verbal intelligence, and NAA levels (Fig. 2) in the left DLPFC and left ACC exclusively in women. This association was strictly region dependent and was only observed for the left frontal cortex, but not for the right DLPFC. These results are consistent with suggestions of Goldstein et al. (2001) that sexual dimorphism in prefrontal regions may explain differences in some aspects of verbal skills. There may

Acknowledgements

This work was supported by an Innovative Medical Research grant (IMF) from the University of Münster, Germany (ER 219918).

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N-acetylaspartate levels of left frontal cortex are associated with verbal intelligence in women but not in men: a proton magnetic resonance spectroscopy study

Abstract

Section snippets

Study population

Gender and age effects on metabolites

Discussion

Acknowledgements

Prog Neuropsychopharmacol Biol Psychiatry

Neuron

Neuroimage

Am J Geriatr Psychiatry

Brain Lang

Steroids

Neuropsycholia

Psychiat Res Neuroimag

Brain Res

Neurobiol Aging

Neuroscience

Progr Neurobiol

Mag Res Imag

Abgrenzung von Hirnarealen auf Grund cytoarchitektonischer Unterschiede

Sexual dimorphism

Am J Psychiatry

Normal sexual dimorphism of the adult human brain assessed by in vivo magnetic resonance imaging

Cereb Cortex

Sex differences in regional cerebral glucose metabolism during resting state

Science

Internationale Diagnosen Checklisten (IDCL) für DSM-IV