AUTHOR=Vasmer David , Pooryasin Atefeh , Riemensperger Thomas , Fiala André TITLE=Induction of aversive learning through thermogenetic activation of Kenyon cell ensembles in Drosophila JOURNAL=Frontiers in Behavioral Neuroscience VOLUME=8 YEAR=2014 URL=https://www.frontiersin.org/journals/behavioral-neuroscience/articles/10.3389/fnbeh.2014.00174 DOI=10.3389/fnbeh.2014.00174 ISSN=1662-5153 ABSTRACT=

Drosophila represents a model organism to analyze neuronal mechanisms underlying learning and memory. Kenyon cells of the Drosophila mushroom body are required for associative odor learning and memory retrieval. But is the mushroom body sufficient to acquire and retrieve an associative memory? To answer this question we have conceived an experimental approach to bypass olfactory sensory input and to thermogenetically activate sparse and random ensembles of Kenyon cells directly. We found that if the artifical activation of Kenyon cell ensembles coincides with a salient, aversive stimulus learning was induced. The animals adjusted their behavior in a subsequent test situation and actively avoided reactivation of these Kenyon cells. Our results show that Kenyon cell activity in coincidence with a salient aversive stimulus can suffice to form an associative memory. Memory retrieval is characterized by a closed feedback loop between a behavioral action and the reactivation of sparse ensembles of Kenyon cells.