Studies at The University of Auckland have shown that moderate levels of alcohol consumption, equivalent to a glass or two of wine a day, can enhance memory. In contrast, high levels of alcohol decrease the ability of new brain cells to develop and mature, and cause an impairment of memory except at times of heightened emotion, when memory is increased.

The study was performed by researchers Dr Maggie Kalev and Professor Matthew During. Results are published in this week’s Journal of Neuroscience.

"Low levels of alcohol promoted neutral memories, such as remembering objects," says Dr Maggie Kalev of the Faculty of Medical and Health Sciences. "However, contrary to popular belief, we also found that excessive levels of alcohol enhanced memories of highly emotional stimuli, meaning the concept of "drinking to forget" is unlikely to be true. Our work suggests that heavy drinking actually reinforces negative memories."

The study also identified the mechanism by which low dose alcohol improves memory. A very important brain receptor, called NMDA receptor, appears required for this process. When rats that did not produce sufficient NMDA receptors were given alcohol, memory improvements were not observed. On the other hand, rats with increased numbers of NMDA receptors mimicked effects of low dose alcohol.

"Pathways by which memory is laid down are unclear, but NMDA receptor is critical in this process. Building on this knowledge may help in the treatment of memory disorders, such as Alzheimer's disease and other dementias. Furthermore, it could assist in designing novel strategies to enhance brain functions in other disease contexts."