title: Reversing Stimulus Timing in Visual Conditioning Leads to Memories with Opposite Valence in Drosophila.
abstract: Animals need to associate different environmental stimuli with each other regardless of whether they temporally overlap or not. Drosophila melanogaster displays olfactory trace conditioning, where an odor is followed by electric shock reinforcement after a temporal gap, leading to conditioned odor avoidance. Reversing the stimulus timing in olfactory conditioning results in the reversal of memory valence such that an odor that follows shock is later on approached (i.e. relief conditioning). Here, we explored the effects of stimulus timing on memory in another sensory modality, using a visual conditioning paradigm. We found that flies form visual memories of opposite valence depending on stimulus timing and can associate a visual stimulus with reinforcement despite being presented with a temporal gap. These results suggest that associative memories with non-overlapping stimuli and the effect of stimulus timing on memory valence are shared across sensory modalities.
authors.affiliation: Max Planck Institute of Neurobiology, 82152, Martinsried, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Vogt
authors.affiliation: Max Planck Institute of Neurobiology, 82152, Martinsried, Germany; Leibniz Institute for Neurobiology (LIN), Research Group Molecular Systems Biology of Learning, 39118, Magdeburg, Germany; Center for Behavioral Brain Sciences, 39118, Magdeburg, Germany.
authors.forename: Ayse
authors.initials: A
authors.lastname: Yarali
authors.affiliation: Max Planck Institute of Neurobiology, 82152, Martinsried, Germany; Tohoku University Graduate School of Life Sciences, 980-8577, Sendai, Japan.
authors.forename: Hiromu
authors.initials: H
authors.lastname: Tanimoto
mesh_terms: D000818:Animals; D003216:Conditioning, Operant; D004330:Drosophila / Q000502:physiology*; D004558:Electric Stimulation; D014785:Vision, Ocular / Q000502:physiology*