Figure 7. Exploratory measures of zebrafish in the novel tank test (Experiment 2).

In general, zebrafish explored the top of the novel tank more across the duration of the novel tank test (6 minutes) by (A) entering the top zone more frequently, (B) spending more time in the top zone, and (C) traveling a longer distance in the top zone. Zebrafish exposed to chronic unpredictable stress (CUS) for 7 days before drug or vehicle treatments entered the top zone significantly more times and traveled a significantly longer distance in the top compared to non-stressed subjects. If fish were chronically treated with prazosin, they spent significantly more time in the top of the tank compared to vehicle-treated fish (N = 16 − 18 in each group).