A novel Y-maze paradigm with enhanced sensitivity to subtle spatial recognition memory impairments in mice
Senka Hadžibegović, Bruno Bontempi, Olivier Nicole
Abstract
Abstract Background Deficits in spatial navigation are commonly observed in normal aging and are among the earliest cognitive symptoms of Alzheimer’s disease (AD). However, many traditional behavioral tests rely on prolonged training, motivational factors or aversive stimuli, compromising their sensitivity and translational relevance for detecting subtle cognitive impairments. To address these limitations, we developed a modified version of the classical Y-maze recognition memory task using an 8-arm radial maze to increase spatial cognitive demand. Methods The modified Y-maze apparatus consisted of a central platform that serves as the starting position for the mouse and three accessible arms arranged in a Y-shape. Mice underwent a single 10-minute training session with access restricted to only two arms, followed by a 10-minute inter-trial interval (ITI) after which their preference toward the previously unexplored arm was tested. Spatial recognition memory was evaluated in both aging and AD mouse models and performance profiles were compared to those obtained in the classical Y-maze task. Effects of task difficulty by extending the ITI to 24 h were also examined. Results Young mice tested in the modified Y-maze task showed a robust preference for the novel arm after the 10-minute ITI. This preference remained significantly above chance level, even after a 24-hour delay and could be further strengthened by repetition of the training phase. Compared to the classical Y-maze, the modified task demonstrated higher sensitivity in detecting mild memory impairments in both aged mice and those with AD-related pathology. Conclusions The modified Y-maze protocol provides a rapid, and highly sensitive measure of spatial recognition memory. It can be easily implemented in standard rodent facilities and offers a valuable tool for detecting subtle cognitive deficits in mouse models of aging and AD, as well as for evaluating treatment interventions. Despite its enhanced sensitivity to detect subtle spatial memory deficits, the modified Y-maze task relies on innate novelty-seeking behavior, a potential confounding variable in animal models in which motivation or exploratory tendencies are altered independently of memory function.