Microstructural and functional correlates of glutamate concentration in the posterior cingulate cortex

Area of Science:

• Neuroscience
• Neuroimaging
• Neurochemistry

Background:

• Glutamate is the primary excitatory neurotransmitter in the human brain.
• It plays a crucial role in brain activity, both intrinsic and stimulus-induced.

Purpose of the Study:

• To investigate the functional and microstructural correlates of glutamate in the posterior cingulate cortex (PCC).
• To explore the relationship between glutamate concentration and brain imaging metrics.

Main Methods:

• 1H magnetic resonance spectroscopy (MRS) at 3T to measure glutamate levels in the PCC.
• Simultaneous electroencephalography and magnetic resonance imaging (EEG-MRI).
• Diffusion tensor imaging (DTI), functional MRI (fMRI), and EEG were employed.

Main Results:

• Glutamate concentration in the PCC showed a significant negative correlation with mean diffusivity in the same area.
• No relationship was found between glutamate levels and resting-state network activity.
• Glutamate correlated positively with alpha-1 frequency electrical generators and negatively with alpha-2 and beta-1 generators.

Conclusions:

• Glutamate concentration in the PCC is associated with microstructural properties and specific EEG frequency bands.
• These findings provide insights into the neurobiological underpinnings of glutamate in the human brain.