Verbal and General IQ Associate with Supragranular Layer Thickness and Cell Properties of the Left Temporal Cortex

D. B. Heyer, R. Wilbers, A. A. Galakhova, E. Hartsema, S. Braak, S. Hunt, M. B. Verhoog, M. L. Muijtjens, E. J. Mertens, S. Idema, J. C. Baayen, P. De Witt Hamer, M. Klein, M. Mcgraw, E. S. Lein, C. P.J. De Kock, H. D. Mansvelder, N. A. Goriounova

Research output: Contribution to journalArticleAcademicpeer-review

10 Citations (Scopus)

Abstract

The left temporal lobe is an integral part of the language system and its cortical structure and function associate with general intelligence. However, whether cortical laminar architecture and cellular properties of this brain area relate to verbal intelligence is unknown. Here, we addressed this using histological analysis and cellular recordings of neurosurgically resected temporal cortex in combination with presurgical IQ scores. We find that subjects with higher general and verbal IQ scores have thicker left (but not right) temporal cortex (Brodmann area 21, BA21). The increased thickness is due to the selective increase in layers 2 and 3 thickness, accompanied by lower neuron densities, and larger dendrites and cell body size of pyramidal neurons in these layers. Furthermore, these neurons sustain faster action potential kinetics, which improves information processing. Our results indicate that verbal mental ability associates with selective adaptations of supragranular layers and their cellular micro-architecture and function in left, but not right temporal cortex.

Original languageEnglish
Article numberbhab330
Pages (from-to)2343–2357
Number of pages15
JournalCerebral cortex (New York, N.Y. : 1991)
Volume32
Issue number11
Early online date21 Sept 2021
DOIs
Publication statusPublished - 1 Jun 2022

Keywords

  • action potential
  • dendrites
  • human neurons
  • intelligence
  • language

Cite this