Immediate perception of a reward is distinct from the reward's long-term salience

• Published in: eLife Vol. 5
• Main Authors: McGinnis, John P, Jiang, Huoqing, Agha, Moutaz Ali, Sanchez, Consuelo Perez, Lange, Jeff, Yu, Zulin, Marion-Poll, Frederic, Si, Kausik
• Format: Journal Article
• Language: English
• Published: England eLife Science Publications, Ltd 22.12.2016; eLife Sciences Publications Ltd; eLife Sciences Publication; eLife Sciences Publications, Ltd
• Subjects: Animals; Arabinose; Arabinose - metabolism; Boxes; Calcium imaging; Drosophila; Drosophila melanogaster; Drosophila melanogaster - physiology; Drosophila Proteins - agonists; Feeding Behavior; Food; Hunger; Insects; L-Arabinose; Life Sciences; Long term memory; memory; Neurogenesis; Neuroscience; Nutrition; Observations; Odors; Perception; Physiology; Preferences; Receptors, Cell Surface - agonists; Reinforcement; Reward; Reward (Psychology); salience; Sensory neurons; Sensory Receptor Cells - drug effects; Sensory Receptor Cells - physiology; Short Report; Sugar; Sweet taste; reward; salience; memory; D. melanogaster; neuroscience
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/elife.22283

Reward perception guides all aspects of animal behavior. However, the relationship between the perceived value of a reward, the latent value of a reward, and the behavioral response remains unclear. Here we report that, given a choice between two sweet and chemically similar sugars-L- and D-arabinose- prefers D- over L- arabinose, but forms long-term memories of L-arabinose more reliably. Behavioral assays indicate that L-arabinose-generated memories require sugar receptor Gr43a, and calcium imaging and electrophysiological recordings indicate that L- and D-arabinose differentially activate Gr43a-expressing neurons. We posit that the immediate valence of a reward is not always predictive of the long-term reinforcement value of that reward, and that a subset of sugar-sensing neurons may generate distinct representations of similar sugars, allowing for rapid assessment of the salient features of various sugar rewards and generation of reward-specific behaviors. However, how sensory neurons communicate information about L-arabinose quality and concentration-features relevant for long-term memory-remains unknown.