Morris Water Maze Spatial Learning Test

The Morris Water Maze (MWM) test was performed as per the method reported in the literature (Morris, 1984 (link); Auti and Kulkarni, 2019 (link)). The MWM consisted of a tank with a 150 cm diameter and 30 cm depth that was filled with water. The round maze was divided into four equal quadrants by marking the edges with tape. A sturdy platform was placed in one of the quadrants. Each animal was exposed to MWM in two phases: the acquisition phase, which lasted from days 17–20, and the retention phase, which lasted from days 21–42. During the acquisition phase, each animal was subjected to four trials with a 10-min gap, and every time it was placed in a different quadrant facing the wall. Each rat was given 120 s to explore the tank and find a platform. If the animal could not locate the platform, it was guided there and allowed to stay. The time taken by the animal to find the platform was recorded as acquisition latency. During the acquisition phase, the platform was visible to the animal, as it was placed 1 cm above the water level; however, during the retention phase, the water in the tank was made opaque, and the platform was placed 1 cm below the water level.