Table 3.

Overview of stress paradigms used to model depression in rodents

Test	Procedure	Common interpretation	Indicator of susceptibility
Forced Swim	Mouse/rat is placed in an inescapable cylinder of water. After initial struggling (swimming, climbing), animals will eventually stop struggling and float immobile. Latency to first become immobile and total time immobile are measured.	‘Behavioral despair’ or passive vs. active coping	Increased immobility
Tail Suspension	Mouse is suspended by tail. After initial struggling, mice stop struggling and hang immobile. Latency to first become immobile and total time immobile are measured.	‘Behavioral despair’ or passive vs. active coping	Increased immobility
Sucrose Preference	Mouse/rat has free access to bottles of water and sucrose solution in home cage or in a discrete test. The volume of each solution consumed is measured and compared to calculate a preference score.	Anhedonia	Decreased preference for sucrose
Social Interaction	Mouse is placed in an arena with a mesh enclosure that is empty on an initial ‘no target’ trial and contains a novel mouse on a ‘target’ trial. Time spent in vicinity of the enclosure (interaction zone) while the social target is present vs absent is measured and used to calculate a social interaction ratio.	Social withdrawal	Reduced time interacting with social target
Open Field	Mouse/rat is placed in an empty arena and time spent exploring the center vs. periphery is measured. Manipulations associated with increased anxiety reduce center exploration.	Anxiety	Reduced time in center
Elevated Plus Maze	Mouse is placed in the center of a plus (+) shaped maze with two walled ‘closed’ arms and two exposed ‘open’ arms. Time spent in open and closed arms is measured. Manipulations associated with increased anxiety reduce time spent in open arms.	Anxiety	Reduced time in open arms