Whole-brain imaging of freely-behaving zebrafish larvae during motor adaptation
Poster No:
1692
Submission Type:
Abstract Submission
Authors:
Sarah Stednitz1, Lilian de Sardenberg Schmid2, Drew Robson2, Jennifer Li3, Ethan Scott1
Institutions:
1University of Melbourne, Melbourne, Victoria, 2Max Planck Institute for Biological Cybernetics, Tuebingen, Baden-Wuerttemberg, 3Max Planck Institute for Biological Cybernetics, Tuebingen, B
First Author:
Co-Author(s):
Lilian de Sardenberg Schmid
Max Planck Institute for Biological Cybernetics
Tuebingen, Baden-Wuerttemberg
Max Planck Institute for Biological Cybernetics
Tuebingen, Baden-Wuerttemberg
Introduction:
Animals must incorporate dynamic sensory information about the surrounding environment, and produce adaptive behavioral responses to changing conditions. Aquatic animals in particular must cope with variation in the ambient viscosity, which is dependent on environmental factors such as temperature, pressure, and dissolved sediment. Zebrafish larvae are no exception, and adapt their swimming behavior to optimally navigate in water and conserve energy. Importantly, these small vertebrates are optically transparent and readily genetically modifiable to express fluorescent calcium indicators that permit whole-brain imaging at single cell resolution. We combine behavioral and brain analysis to better understand how the vertebrate brain incorporates changing sensory information to subsequently modify motor output.
Methods:
We used a tracking microscope that permits whole-brain single-cell resolution imaging in freely-behaving larvae to record brain activity during repeated exposure to high-viscosity medium (Kim et al, 2017). High-viscosity medium was delivered via a microfluidic system in a glass chamber. We captured the full brain volume of larvae expressing the genetically encoded calcium indicator GCaMP8s at a rate of 2 Hz using DIFF optical sectioning to reconstruct individual planes, while simultaneously recording behavior at 250 Hz. These volumes are then computationally registered to a uniform anatomical atlas, and calcium traces from single neurons extracted using non-negative matrix factorization to produce a dataset comprised of approximately 80,000 neurons per animal. We subsequently use time-series regression analyses to relate calcium signals to behavioral metrics, such as the kinematics of motor behavior and speed of adaptation on subsequent exposures.
Results:
Larvae modify their swimming behavior to achieve equal displacement to their standard water conditions when challenged with high-viscosity water. This is achieved primarily through increasing the duration of individual movement bouts, though individuals vary their strategies and may increase the vigor of an individual swim. Further, prior exposure leads to faster adaptation in subsequent trials, indicative of short-term motor learning. From our calcium imaging dataset, we identified flow-responsive neurons and motor command regions in the hindbrain that correspond to kinematic features of swim bouts, including the amplitude and frequency of tail movements. We further identified a region of the cerebellum that predicts whether or not motor adaptation has occurred on an individual basis, independent of adaptation strategy.
Conclusions:
We provide evidence that the small vertebrate zebrafish is capable of both motor adaptation and improved performance after repeated trials in response to a naturalistic environmental challenge. These experiments lay the groundwork for optogenetic manipulation of the cerebellum to potentially demonstrate a neural substrate of learning in a vertebrate model, and further modeling of the sensory landscape that animals use to response adaptively to environmental stressors.
Learning and Memory:
Learning and Memory Other
Modeling and Analysis Methods:
Other Methods
Motor Behavior:
Motor Behavior Other 1
Neuroanatomy, Physiology, Metabolism and Neurotransmission:
Neuroanatomy Other
Novel Imaging Acquisition Methods:
Imaging Methods Other 2
Keywords:
Computational Neuroscience
Memory
Motor
Neuron
Optical Imaging Systems (OIS)
Other - cerebellum
1|2Indicates the priority used for review
