Y-Maze Novel Arm Recognition

The Y-maze novel arm recognition test is a two-phase spatial memory paradigm that exploits the innate preference of rodents for exploring previously inaccessible environments. During the exposure phase, the animal explores two of the three arms freely while the third arm is blocked by a guillotine door or removable insert. After a retention interval that can range from one minute to twenty-four hours, the animal is returned to the maze with all three arms accessible. Intact animals preferentially explore the novel (previously blocked) arm, and the magnitude of this preference serves as an index of spatial recognition memory.

The critical outcome measure is the proportion of time spent in the novel arm during the first two to five minutes of the test phase, compared against the 33.3% chance level. Complementary metrics include the discrimination index, number of entries into each arm, latency to first novel arm entry, and locomotor activity. Unlike spontaneous alternation which relies on short-term sequential choices, novel arm recognition tests a distinct recognition memory process that is sensitive to both hippocampal and perirhinal cortex function depending on the delay length employed.

ConductMaze implements this protocol with automated guillotine door actuation synchronized to video tracking, ensuring precise phase timing and consistent arm blocking across subjects. The software defines arm zones, records continuous position data throughout both phases, and computes all preference measures automatically. Phase transitions are logged with millisecond timestamps, and configurable alerts warn experimenters if animals fail to explore during either phase, enabling real-time exclusion decisions.