GABA predicts visual intelligence

Emily Cook,Stephen T Hammett,Jonas Larsson

doi:10.1016/j.neulet.2016.07.053

Emily Cook, Stephen T Hammett + Show 1 more

Open Access

https://doi.org/10.1016/j.neulet.2016.07.053

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Journal: Neuroscience letters	Publication Date: Aug 2, 2016
Citations: 41	License type: cc-by

Affiliation: Royal Holloway University of London

Abstract

Early psychological researchers proposed a link between intelligence and low-level perceptual performance. It was recently suggested that this link is driven by individual variations in the ability to suppress irrelevant information, evidenced by the observation of strong correlations between perceptual surround suppression and cognitive performance. However, the neural mechanisms underlying such a link remain unclear. A candidate mechanism is neural inhibition by gamma-aminobutyric acid (GABA), but direct experimental support for GABA-mediated inhibition underlying suppression is inconsistent. Here we report evidence consistent with a global suppressive mechanism involving GABA underlying the link between sensory performance and intelligence. We measured visual cortical GABA concentration, visuo-spatial intelligence and visual surround suppression in a group of healthy adults. Levels of GABA were strongly predictive of both intelligence and surround suppression, with higher levels of intelligence associated with higher levels of GABA and stronger surround suppression. These results indicate that GABA-mediated neural inhibition may be a key factor determining cognitive performance and suggests a physiological mechanism linking surround suppression and intelligence.

Highlights

It has long been argued that intelligence represents some fundamental property of the brain [1,2] that should be reflected in low-level visual abilities
The two measures of surround suppression were not significantly correlated (P > 0.1). These results demonstrate an association between cortical gamma-aminobutyric acid (GABA) levels and measures of intelligence, and provide evidence of a relationship between GABA and surround suppression magnitude in typical individuals
A link between GABA and first-order surround suppression has previously been shown for schizophrenic patients, and typical individuals to a lesser extent [9]; our data confirm and extend these findings

Summary

Introduction

It has long been argued that intelligence represents some fundamental property of the brain [1,2] that should be reflected in low-level visual abilities. Visual surround suppression has been shown to correlate with differences in cortical GABA levels in individuals with schizophrenia relative to controls [9], suggesting a role for neural inhibitory mechanisms in mediating this link. Both GABA [10] and some measures of surround suppression [11] have been shown to decline with age, and GABA has been linked to age-related cognitive decline [12]. We measured individual variations in cortical GABA levels, visuo-spatial intelligence and perceptual surround suppression in a group of typical individuals, providing evidence that GABA-mediated neural inhibition is strongly linked to both visual intelligence and susceptibility to surround suppression

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