To Favor Survival Under Food Shortage, the Brain Disables Costly Memory

Abstract

Hunger and Memory During starvation, are all brain functions slowed down, or are specific functions disabled to save energy? Plaçais and Preat (p. 440 ) investigated how the brain of Drosophila deals with severe resource limitation. The brain cut selected expenses to reduce the threat to survival and switched off the formation of aversive long-term memory that depends on costly protein synthesis. However, Hirano et al. (p. 443 ) focused on mild food-deprivation, which actually enhanced long-term memory formation. Presumably, improved memory should enhance survival when competing for limited food. After longer food deprivation, enhancement of aversive long-term memory decreased, while that of appetitive long-term memory remained high: Presumably, as starvation nears, it becomes more important to pursue food at all costs, and so appetitive memory takes precedence over aversive memories.