MODULE 06 // ARCHITECTURE

The Fuel: Glutamate & GABA

For decades, we focused on Monoamines: Serotonin, Dopamine, and Norepinephrine. These are important, but they are merely the "modulators" of the brain—the volume knobs. They account for less than 15% of neurotransmission.

The real heavy lifting is done by two systems that account for over 80% of brain activity: Glutamate (The Gas) and GABA (The Brakes).

Glutamate: The Master Switch

Glutamate is the brain's primary excitatory neurotransmitter. It tells neurons to FIRE. It is essential for learning, memory, and cognition. But too much Glutamate leads to "Excitotoxicity"—the neurons literally burn themselves out firing too hard. This is often what happens in chronic stress.

GABA: The Cooling System

GABA (Gamma-Aminobutyric Acid) is the primary inhibitory neurotransmitter. It tells neurons to CHILL. Benzodiazepines (Xanax, Valium) work on this system, forcing relaxation. But they are addictive band-aids.

The NMDA Receptor: This is the critical junction. The NMDA receptor is a specific type of Glutamate receptor. It helps regulate synaptic plasticity (learning). In depression, these receptors can become "stuck" or dysregulated.

Ketamine is unique because it is an NMDA Antagonist. It blocks these receptors temporarily. This blockade triggers a paradox: a surge of Glutamate followed by a rapid regrowth of synaptic connections (Synaptogenesis). It doesn't just add oil (like SSRIs); it rebuilds the engine.

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