it, abbreviating gamma-aminobutyric acid, is the brain’s main inhibitory neurotransmitter. Throughout neural circuits, it functions as the brake that helps regulate neuronal activity, maintaining a stable baseline in areas such as the cortex, hippocampus, thalamus, and brainstem. Because it influences how easily neurons fire, it plays a key role in determining the brain’s overall excitability and information processing. It signals through two primary receptor families: GABA-A, which forms rapid, chloride-permeable channels, and GABA-B, which is metabotropic and produces slower, longer-lasting effects via intracellular signaling. A third type, GABA-C (now called GABA-A rho), operates in specific retinal circuits and certain brain regions. When GABA binds to these receptors, it changes the electrical state of neurons, affecting how they respond to other inputs and how networks synchronize. Researchers examine GABA’s role in sleep regulation, anxiety, and stress by studying network dynamics rather than isolated effects. For instance, GABAergic interneurons coordinate rhythms and synchronize activity across brain regions such as the amygdala, hypothalamus, and prefrontal cortex, all involved in arousal and emotion processing. Variations in GABA signaling can alter the balance between excitation and inhibition, influencing how neural circuits process information during different states. To investigate GABA in the lab, scientists employ various methods, including electrophysiology, imaging, genetic models, and biochemical assays. Techniques like magnetic resonance spectroscopy can measure GABA levels in living tissue, while optogenetics and chemogenetics provide precise control over GABAergic neurons in animal experiments. These approaches collectively help uncover how GABA contributes to the brain’s inhibitory tone and regulates complex cognitive and emotional functions.
