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bioRxiv · 10.1101/2022.07.20.500885

Optogenetically induced reward and 'frustration' memory in larval Drosophila

Thoener, J.·Weiglein, A.·Gerber, B.·Schleyer, M.
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Abstract

Humans and animals alike form oppositely valenced memories for stimuli that predict the occurrence versus the termination of a reward: appetitive reward memory for stimuli associated with the occurrence of a reward and aversive frustration memory for stimuli that are associated with its termination. We characterize these memories in larval Drosophila using a combination of Pavlovian conditioning, optogenetic activation of the dopaminergic central-brain DAN-i1864 neuron, and high-resolution video-tracking. This reveals their dependency on the number of training trials and the duration of DAN-i1864 activation, their temporal stability, and the parameters of locomotion that are modulated during memory expression. Together with previous results on punishment versus relief learning by DAN-f1 neuron activation, this reveals a 2x2 matrix of timing-dependent memory valence for the occurrence/ termination of reward/ punishment. These findings should aid the understanding and modelling of how brains decipher the predictive, causal structure of events around a target reinforcing occurrence.

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Thoener, J., Weiglein, A., Gerber, B., Schleyer, M.. 2022-07-22. Optogenetically induced reward and 'frustration' memory in larval Drosophila. https://doi.org/10.1101/2022.07.20.500885

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