Description
Features |
Length: 52 cm |
Width: 17cm |
Height: 23cm |
Middle section width : 8.5cm |
Comes with 4 Dividers |
(2) 8 Hole pattern |
(2) Solid Clear Acrylic |

Introduction
Zebrafish conditioned place preference (CPP) is a popular method for evaluating the rewarding effects of various food substances and psychoactive compounds. This task assesses the positive-reinforcing effects by measuring the zebrafish’s preference for an environment that was previously associated with a particular substance.
The CPP paradigm leverages the zebrafish’s natural preference for black over white. In this assay, the primary stimulus acts as an unconditioned stimulus. When paired with a secondary stimulus (a visual cue) that functions as a conditioned stimulus, it induces an approach behavior towards the paired environment (Darland & Dowling, 2001).
The CPP procedure is typically divided into three phases. In Phase I, zebrafish can explore all compartments of the CPP tank freely, and the time spent in each compartment is recorded to establish a baseline preference. In Phase II, the fish are confined to each compartment and receive either the experimental or control treatment for a set period. During Phase III, zebrafish are again allowed to move freely between compartments, and the time spent in each is recorded to determine their final preference. CPP behavior is quantitatively assessed by subtracting the baseline preference recorded in Phase I from the final preference observed in Phase III.
Quantitative measure of CPP behavior =Ā Ā (Final place preference ā Baseline place preference).
A significant shift towards the compartment conditioned with the experimental treatment indicates that the treatment is rewarding (Mathur et al., 2011).
Darland and Dowling were the trailblazers in developing the CPP behavior model for adult zebrafish (Darland & Dowling, 2001). They created an apparatus specifically to assess the addictive properties of various compounds. In their study, they initially recorded the baseline place preference, then confined the zebrafish to their least preferred compartment while exposing them to cocaine, and finally assessed the change in place preference to determine the effects.
Apparatus and Equipment
The apparatus comprises a Plexiglas CPP tank measuring approximately 52 cm in length, 17 cm in width, and 22 cm in height. It is divided by two opaque barriersāone solid and one perforatedācreating a central alley for the zebrafish to enter. To prevent the fish from seeing the experimenter, the tank is housed inside a brown box. Various floor patterns can be used as visual cues, with the most effective method being to place patterned sheets beneath the apparatus.
The fishās movements within the CPP tank can be monitored using Noldus EthoVision XT, which is positioned on an overhead rack above the tank. The floor patterns should provide sufficient contrast to ensure consistent tracking by the Noldus EthoVision XT without any obstructions.
Training Protocol
The CPP paradigm aims to assess the reinforcing effects of substances in zebrafish by comparing baseline and final place preference behavior between a vehicle-treated control group and a disease model or intervention group.
Modifications
The original CPP tank for zebrafish was created by Darland and Dowling. Their design featured a tank divided into two distinct compartments with visual cues: one with a white pattern and the other with a dotted pattern. Since then, various modifications have been made to the CPP paradigm, including changes to the floor and tank patterns.
Ninkovic et al. examined the reinforcing effects of substances using a CPP tank. Their setup included two chambers with distinct compartments, one colored brown and the other white, and the tank floor featured two black circles.
Kily et al. investigated the effects of different substances with the CPP task by modifying the apparatus to include two chambers: one side with black spots and the other with alternating black and white stripes.
Mathur et al. used the CPP model to study the effects of several compounds. In their design, the tank was divided into white and dotted halves by an approximately 8 cm wide central alley. The dotted compartment featured a uniform pattern of 16 blue dots, each about 2 cm in diameter.
Sample Data

The sample data illustrates the correlation between ethanol concentration and the change in preference percentage in zebrafish. The graph clearly shows that as the ethanol concentration in the CPP tank increases, the zebrafish spend more time in the conditioned compartment.
Strengths and Limitations
Summary
- CPP is a widely used paradigm to evaluate the rewarding effects of psychoactive substances.
- The apparatus consists of a CPP tank, and a wide range of flooring patterns sheets can be used.
- Baseline place preference and final place preference is evaluated with the task.
- Numerous modifications have been made to the CPP paradigm with slight changes in the floor and tank patterns.