A Parallelized, Automated System for Higher-Throughput Spatial Navigation Testing of Rats.

Spatial navigation tasks for rodents have been an extremely useful tool for studying cognitive processes for decades, but are often laborious to admin- ister and sensitive to experimenter-induced variability. To address these limitations, we have developed a parallelized maze system which runs four highly flexible maze environments simultaneously with automated reward delivery, enabling reduced experimenter involvement, increased throughput, and streamlined data collection. Further, our software tracks subject perfor- mance and manages the progression through a pre-set curriculum as subjects learn, reducing experimenter error and ensuring comparable learning curves across cohorts. Equipped with IR beam-break based reward ports, peri- staltic pumps for liquid reward delivery, and overhead video tracking, our current maze accessories can be flexibly reconfigured to enable a vast array of behavioral tasks and support a wide range of experimental questions. Pilot cohorts of young (4-8 month) and aged (28-32 month) male and female rats demonstrate that this apparatus enables the efficient training of a series of increasingly difficult visually cued and memory-dependent spatial navigation task variants across a wide range of performance abilities.Significance Statement To increase the efficiency and reliability of spatial navigation task ad- ministration, we have designed a behavioral apparatus which enables the training of four subjects in parallel on a variety of tasks with automated re- ward delivery. Further, we developed software to track subject performance and advance training parameters through a pre-set curriculum to reduce ex- perimenter error and enable robust comparison of learning metrics across cohorts.