Melatonin is a neurohormone produced by the pineal gland and secreted into the body in a circadian rhythm. Melatonin is known to be involved in many vital body functions, including sleep, reproduction, and immune response. Exogenous melatonin, sold as over the counter natural supplements in drugstores, is commonly taken by many people to help cure various ailments. Melatonin also plays a role in the hippocampus. This paper investigates the effects of melatonin on long-term potentiation in the hippocampus. Long-term potentiation, described as a long-lasting strengthening of synapses between nerve cells, is thought to be responsible for long-term memory retention. It is found that melatonin has a negative effect on long-term potentiation, inhibiting its magnitude. As long-term potentiation is related to some forms of learning and memory, melatonin inhibits learning and memory too. The practice of taking melatonin supplements causes one’s long-term potentiation to be inhibited to a greater degree than it would be under normal conditions and can significantly impact one’s learning and memory. In conclusion, although more studies need to be conducted, one should be wary and display caution before using melatonin supplements with any regularity
