Figure 1.

Impaired behavioral flexibility in adult mice born to dams that were administered NaAsO₂ during gestation. (A) Overview of an IntelliCage apparatus. (B) Behavioral sequencing task. Mice were allowed to make an access to water as a reward for 4 s during their visits at an active reward corner (blue circle). The location of the active reward corner was automatically alternated to a diagonally opposed corner each time the mouse received a reward. Therefore, mice obtained rewards continuously by acquiring a behavioral sequence (alternating between the two reward corners). A visit to a never-rewarded corner (black circle) was counted as a discrimination error. (C) Serial reversal task. For each mouse, the assigned spatial patterns of the rewarded corners (sequence 1 or sequence 2) were reversed 11 times every 3 or 8 sessions. (D) Timeline of the experiment for each day. (E) Learning performance of control or NaAsO₂-exposed female mice in the behavioral flexibility test. Discrimination error rates (the number of discrimination errors in the first 100 corner visits of a session) are expressed as mean ± SEM (control group n = 8, NaAsO₂-exposed group n = 6). An asterisk indicates a statistical difference (p < 0.05) from the control group.