Oiling the gears of memory: quercetin exposure during memory formation, consolidation, and recall enhances memory in Lymnaea stagnalis

Memory formation (short-term, intermediate-term, and long-term) is an integral process of cognition which allows individuals to retain important information and is influenced by various intrinsic and extrinsic factors. A major extrinsic factor influencing cognition across taxa is diet, which may contain rich sources of molecular agents with antioxidant, anti-inflammatory, and memory enhancing properties that potentially enhance cognitive ability. A common and abundant flavonoid present in numerous food substances is quercetin (Q) which is also known to upregulate cyclic AMP response element binding protein (CREB) in several animals including our model system Lymnaea stagnalis. Since CREB is known to be involved in long term memory (LTM) formation, we investigated the role of Q-exposure on memory formation, consolidation, and recall during operant conditioning of aerial respiratory behaviour in Lymnaea. Snails were exposed to Q 3h before or after training to ascertain its effects on LTM. Additionally, we investigated the effect of the combined presentation of a single reinforcing stimulus (at 24h post-training or 24h before training) and Q-exposure on both LTM formation and reconsolidation. Our data indicate that Q-exposure acts on the different phases of memory formation, consolidation, and recall leading to enhanced LTM formation.