Figure 3

An overhead view of the open field used in the OFT and ORT. In the OFT, we divided the oblong field (55 cm × 40 cm) into three subdivisions of center (gray; 15 cm × 10 cm), intermediate (white; 25 cm × 20 cm), and peripheral (black) and counted the number of entrances for each subdivision in addition to measuring the total path length. In the ORT, two objects were placed at the positions indicated as “R (object on the right)” and “L (object on the left)”, and time spent to explore each object was measured. In all experiments, the mouse was always placed at the position “M” at the beginning of the test, with its face oriented to the wall.