4-Aminobutyric acid / GABA & Lactobacillus

Magnetic resonance spectroscopy reveals oral Lactobacillus promotes increases in brain 4-Aminobutyric acid / GABA, N-acetyl aspartate, and glutamate
Janik et al. 2016 Neuroimage 125: 988-995

However, whether this happens via a damaged blood-brain barrier - 4-Aminobutyric acid / GABA cannot cross an intact one - or through increased 4-Aminobutyric acid / GABA synthesis in the brain or through vagal stimulation with increased levels in the cerebrospinal fluid remains to be clarified
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