Figure 1.

Schematic representation of open field test and novel object test

A: Open field test with heart rate variation (HRV) data was defined as a non-restrained test where animal could freely move within a defined testing area, and HRV test measured activity of autonomous nervous system. B: Novel object test was used to assess the animal’s response to an inanimate yellow duck. In our test, we determined activity of autonomous nervous system for different cognitive states. Compared with movement represented in gray, movements represented in light gray occurred earlier.