The Three-Chamber Choice Behavioral Task using Zebrafish as a Model System

Summary

We present a behavioral chamber designed to assess cognitive performance. We provide data showing that once acquired, zebrafish remember the task 8 weeks later. We also show that hyperglycemic zebrafish have altered cognitive performance, indicating that this paradigm is applicable to studies assessing cognition and memory.

Abstract

Neurodegenerative diseases are age-dependent, debilitating, and incurable. Recent reports have also correlated hyperglycemia with changes in memory and/or cognitive impairment. We have modified and developed a three-chamber choice cognitive task similar to that used with rodents for use with hyperglycemic zebrafish. The testing chamber consists of a centrally located starting chamber and two choice compartments on either side, with a shoal of conspecifics used as the reward. We provide data showing that once acquired, zebrafish remember the task at least 8 weeks later. Our data indicate that zebrafish respond robustly to this reward, and we have identified cognitive deficits in hyperglycemic fish after 4 weeks of treatment. This behavioral assay may also be applicable to other studies related to cognition and memory.

Introduction

Neurodegenerative diseases are age-dependent, debilitating, and incurable. These diseases are increasing in prevalence, resulting in an urgent need to improve upon and develop new therapeutic strategies. The onset and presentation of each disease is unique, as some affect language, motor, and autonomic brain regions, while others cause learning deficits and memory loss¹. Most notably, cognitive deficits and/or impairment are the most prevalent complications across all neurodegenerative diseases². In hopes of shedding light on the underlying mechanisms involved in these neurodegenerative diseases, the use of many differen....

Protocol

All experimental procedures were approved by the Institutional Animal Care and Use Committee (IACUC) at American University (protocol # 1606, 19-02).

1. Animals

1. Animal rearing and maintenance
   1. Obtain adult wild-type zebrafish (Danio rerio) aged 4–11 months as embryos and rear them in-house.
   2. Maintain the fish in an aquatic rack system at 28–29 °C on a 14-h light:10-h dark photoperiod.
   3. Feed the fish twice per day with commercial flakes and supplement with live Artemia.
   4. Choose fish randomly from these stock tanks for behavioral experiments.
   ....

Results

Acclimation to the behavior chamber involves three days of training: 2 days of group acclimation followed by 1 day of individual acclimation. However, because we could not distinguish individual zebrafish from one another, we were only able to collect data during individual acclimation. At this time, experimental animals (n = 30), conditioned using a shoal-based reward, took an average of 125.11 s to reach their first decision (Figure 2A) and an average of 725.34 s (12 min) to complete the e.......

Discussion

Although there has been tremendous growth in the amount and variety of neuroscience research performed using zebrafish in the past 15 years²⁴, behavioral assays are lacking in this species compared to mammalian model systems^11,25,26. Here, we show that a three-chamber choice task developed for use with rodents can be adapted to assess the acquisition and reversal of a visual discrimination learning in zeb.......

Materials

Name	Company	Catalog Number	Comments
Champion Sports Stopwatch Timer Set: Waterproof, Handheld Digital Clock Sport Stopwatches with Large Display for Kids or Coach - Bright Colored 6 Pack	Amazon	N/A	https://www.amazon.com/Champion-Sports-910SET-Stopwatch-Timer/dp/B001CD9LJK/ref=sr_1_17?dchild=1&keywords=stopwatch+for+sports&qid=1597081570&sr=8-17 Recommend two of different colors; one for choice latency and one for time to completion
Coofficer Extra Large Binder Clips 2-Inch (24 Pack), Big Paper Clamps for Office Supplies, Black	Amazon	N/A	https://www.amazon.com/Coofficer-Binder-2-Inch-Clamps-Supplies/dp/B07C94YCR5/ref=sr_1_3_sspa?dchild=1&keywords=large+binder+clips&qid=1597081521&sr=8-3-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExUENWUTRZVjlIWEVPJmVuY3J5cHRlZElkPUEwNDQ5NDU0MlpSREkwTFlLSThVQiZlbmNyeXB0ZWRBZElkPUEwMTg5NDI3MllRV1EzOUdWTVpSOCZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
Marineland® Silicone Aquarium Sealant	Petsmart	Item #2431002
PVC (Polyvinyl Chloride) Sheet, Opaque Gray, Standard Tolerance, UL 94/ASTM D1784, 0.125" Thickness, 12" Width, 24" Length	Amazon	N/A	https://www.amazon.com/Polyvinyl-Chloride-Standard-Tolerance-Thickness/dp/B000MAMGEQ/ref=sr_1_2?dchild=1&keywords=grey+PVC+sheet&qid=1597081440&sr=8-2
Steelworks 1/4-in W x 8-ft L Mill Finished Aluminum Weldable Trim U-shaped Channel	Lowes	Item #55979Model #11377	https://www.lowes.com/pd/Steelworks-1-4-in-W-x-8-ft-L-Mill-Finished-Aluminum-Weldable-Trim-Channel/3058181
Tetra 10 Gallon Fish tank	Petsmart	Item #5271256
Top Fin Fine Mesh Fish Net (3 in)	Petsmart	Item #5175115