Like many mammals, rats are attracted to novelty. In order to recognize something in the environment as novel, there needs to be memory for what has been encountered before. The relative attention the animal will devote to the novel compared to the familiar in the environment can therefore be used as a proxy for available memory.The novel object recognition task makes use of this effect and is widely employed in memory research, where it is considered a good model for human declarative memory. With lab- and task-specific optimizations, the task produces robust, reliable results.

In our lab, the task typically consists of three phases – Habituation, Sampling, and Probe.

1. Habituation. Animals are repeatedly exposed to the testing environment. We use an open field, 600 mm X 600 mm X 600 mm. Typically, they explore the empty open field one time per day for four consecutive days.
2. Sampling. Objects are now placed in the open field, and rats are returned to the open field. It depends on the experimental question how long and how often this is done. Typically, we place two identical copies of objects in the same positions into the open field during the Sampling trials.
3. Probe. At least one novel object is introduced in the Probe trial.

During Habituation, animals are repeatedly exposed to the square open field. This serves to familiarize them to this environment. Then, during Sampling, animals return to the open field, that now contains objects. In the most simple form,

Typically, animals are exposed to objects in a familiar open field during the Sampling phase, and at a later point, they are re-exposed to the open field during the Probe phase, in which some objects from the Sampling phase have been replaced