Alpha GPC (L-alpha-Glycerylphosphorylcholine) is a natural physiological precursor of acetylcholine, a neurotransmitter involved in memory and other cognitive functions. Alpha GPC is more bioavailable than other forms of choline and is known to cross the blood-brain barrier. In the brain and other nervous tissues, Alpha GPC becomes a constituent of cell membranes. Clinical studies have shown that Alpha GPC intake can support the brain's synthesis of acetylcholine. In this way, it helps promote normal cognitive function and mental acuity.