Glutamine/glutamate (Glx) concentration in prefrontal cortex predicts reversal learning performance in the marmoset

Behav Brain Res. 2018 Jul 2;346:11-15. doi: 10.1016/j.bbr.2018.01.025. Epub 2018 Jan 31.


This study used Magnetic Resonance Spectroscopy (MRS) to identify potential neurometabolitic markers of cognitive performance in male (n = 7) and female (n = 8) middle-aged (∼5 years old) common marmosets (Callithrix jacchus). Anesthetized marmosets were scanned with a 4.7 T/40 cm horizontal magnet equipped with 450 mT/m magnetic field gradients and a 20 G/cm magnetic field gradient insert, within 3 months of completing the CANTAB serial Reversal Learning task. Neurometabolite concentrations of N-Acetyl Asparate, Myo-Inositol, Choline, Phosphocreatine + creatine, Glutamate and Glutamine were acquired from a 3 mm3 voxel positioned in the Prefrontal Cortex (PFC). Males acquired the reversals (but not simple discriminations) faster than the females. Higher PFC Glx (glutamate + glutamine) concentration was associated with faster acquisition of the reversals. Interestingly, the correlation between cognitive performance and Glx was significant in males, but not in females. These results suggest that MRS is a useful tool to identify biochemical markers of cognitive performance in the healthy nonhuman primate brain and that biological sex modulates the relationship between neurochemical composition and cognition.

Keywords: Cognition; Magnetic resonance spectroscopy; Monkey; Primate; Sex differences.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Callithrix
  • Female
  • Glutamic Acid / metabolism*
  • Glutamine / metabolism*
  • Magnetic Resonance Spectroscopy
  • Male
  • Neuropsychological Tests
  • Prefrontal Cortex / diagnostic imaging
  • Prefrontal Cortex / metabolism*
  • Reversal Learning / physiology*
  • Sex Characteristics


  • Glutamine
  • Glutamic Acid