From time immemorial humans have struggled with imperfect memory. Memory enhancing supplements have been around for ages, such as ginkgo-biloba, a plant extract used by our early ancestors and by people today, which purportedly improves memory. More recently, fish oil has been touted to achieve the same end. There is little credible evidence, however, to support claims that extracts and supplements such as these confer any significant memory benefit.
Memory research today continues to seek to unlock the mysteries of memory and to better understand the underlying mechanisms of memory formation (initial creation of a memory or memories) and memory consolidation (reinforcing a memory or memories). For humans, the main olfactory system detects volatile chemicals, and the accessory olfactory system detects fluid-phase chemicals. Olfaction is a form of chemoreception. The chemicals themselves that activate the olfactory system, in general, at very low concentrations, are called odorants. Recently, Bjöorn Rasch, Christian Büchel, Steffen Gais, Jan Born, in “Odor Cues During Slow-Wave Sleep Prompt Declarative Memory Consolidation”, Science 9 Mar. 2007: Vol. 315, no. 5817, pp. 1426-1429, DOI: 10.1126/science. 1138581, hereby incorporated in its entirety by reference herein to the fullest extent permitted by applicable law, demonstrated that an olfactory stimulant, applied at the appropriate times, e.g., during memory formation and again during memory consolidation, can significantly enhance declarative memory.