Experience, circuit dynamics and forebrain recruitment in larval zebrafish prey capture
Abstract
Experience strongly influences behavior, but little is known about how experience is encoded in the brain, and how changes in neural activity are implemented at a network level to improve performance. Here we investigate how differences in experience impact brain circuitry and behavior in larval zebrafish prey capture. We find that experience of live prey compared to inert food increases capture success by boosting capture initiation. To explore the underlying neural basis, we studied the effects of prior experience of live prey on behavior and brain activity. In response to live prey, animals with and without prior experience of live prey all show activity in visual areas (pretectum and optic tectum) and motor areas (cerebellum and hindbrain), with similar visual area retinotopic maps of prey position. However, prey-experienced animals more readily initiate capture in response to visual area activity and also have greater visually-evoked activity in two forebrain areas: the telencephalon and the habenula. Consistent with the contribution of the forebrain to prey capture, disruption of neurons in the habenula reduced prey capture performance in prey-experienced fish. Together, our results suggest that experience of prey strengthens prey-associated visual drive to the forebrain, and that this lowers the threshold for prey-associated visual activity to trigger activity in motor areas, thereby improving capture performance.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures.
Article and author information
Author details
Funding
Defense Advanced Research Projects Agency (N66001-17-C-4015)
- Ehud Y Isacoff
National Institutes of Health (2PN2EY018241)
- Ehud Y Isacoff
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (ACUC) of the University of California, Berkeley.protocol ID: UP-2015-06-7705-1, last approval date 11/20/2019).
Copyright
© 2020, Oldfield et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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