Impulsive decision-making and gambling severity: The influence of γ-amino-butyric acid (GABA) and glutamate-glutamine (Glx)

Eur Neuropsychopharmacol. 2020 Mar:32:36-46. doi: 10.1016/j.euroneuro.2019.12.110. Epub 2019 Dec 31.


Discounting larger, delayed rewards for smaller, immediate rewards is a stable psychological trait known to be impaired in gambling disorder (GD). Neuroimaging with non-GD populations indicates involvement of anterior cingulate (ACC) and dorsolateral prefrontal cortex (dlPFC) in delay discounting. However, little is known about the role of intrinsic properties of brain functioning, such as neurotransmitter action, in impaired discounting in GD. Here, we used magnetic resonance spectroscopy to assess glutamate-glutamine (Glx) and γ-amino-butyric acid (GABA+) concentrations in the dorsal ACC (dACC), dlPFC and occipital cortex of human males with and without GD. Gambling symptom severity correlated negatively with Glx levels in the dACC and occipital voxels. Discounting of small and medium delayed rewards was negatively associated with GABA+ in the dACC, while the discounting of large delayed rewards was negatively associated with GABA+/Glx ratios in the dlPFC. Additionally, in GD, discounting of large delayed rewards was negatively correlated with occipital GABA+ levels. Overall, these findings show that high gambling symptom severity is associated with low levels of Glx and that dACC (GABA+), right dlPFC (GABA+/Glx), and occipital areas (GABA+) track the magnitude of delayed rewards during discounting.

Keywords: Delay discounting; Gambling disorder; Glutamate-glutamine; Magnetic resonance spectroscopy; γ-amino-butyric acid.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Decision Making / physiology*
  • Delay Discounting / physiology
  • Gambling / diagnostic imaging
  • Gambling / metabolism*
  • Glutamic Acid / metabolism*
  • Glutamine / metabolism*
  • Humans
  • Impulsive Behavior / physiology*
  • Magnetic Resonance Spectroscopy / methods
  • Male
  • Middle Aged
  • Occipital Lobe / diagnostic imaging
  • Occipital Lobe / metabolism
  • gamma-Aminobutyric Acid / metabolism*


  • Glutamine
  • Glutamic Acid
  • gamma-Aminobutyric Acid