Learning And Memory In Zebrafish Larvae

• Main Author: Leong, Yew Sum
• Format: Final Year Project / Dissertation / Thesis
• Published: 2020
• Subjects: R Medicine (General)
• Online Access: http://eprints.utar.edu.my/4230/1/BI2_1501647_FYPreport_%2D_YEW_SUM_LEONG.pdf; http://eprints.utar.edu.my/4230/

Understanding the mechanisms of learning and memory can be challenging due to the intricacy of the brain circuits and the constrained capability to observe neuronal activity in vivo. Zebrafish (Danio Rerio) is an emerging animal model which solves these complications due to their high behavioral repertoire and manageable brain. Over the years, different types of learning and memory tests have been devised but they were mostly catered for rodents, and limited behavioral paradigms were designed for zebrafish. In this project, a new test was developed to study the learning and memory in zebrafish larvae. Unlike the previous tests which associates cues with rewards or shocks, this test incorporates a colored T maze with light stimulus. The choice of color for T maze is based on the natural color preference of zebrafish larvae with blue as the most preferred color and yellow as the least preferred color. Light stimulus (red laser beam) was used to train the larvae to swim towards the correct pool. Zebrafish larvae treated with MK-801 (schizophrenic model) and morphine (drug abuse model) were found to take a significantly longer time to learn to swim to the correct (yellow) arm compared to the control, with the morphine-treated larvae spent the longest time, indicating different levels of cognitive deficit. This test opens a new avenue for investigating the effects of pharmacological manipulations of learning and memory in larval zebrafish, and provides an association of cognitive deficits between schizophrenia and drug abuse.