Immobility in the forced swim test is adaptive and does not reflect depression

Psychoneuroendocrinology. 2015 Dec;62:389-91. doi: 10.1016/j.psyneuen.2015.08.028. Epub 2015 Sep 2.


The forced swim test is based on the progressive immobility a rodent displays when immersed in a beaker filled with water from where no escape is possible. While the test was originally designed to identify the antidepressant potential of drugs, over the past decade a rapidly growing number of publications (more than 2000) portray this immobility response anthropomorphically as a measure for depression and despair. This is incorrect. The response to the forced swim stressor should be considered for what it shows: a switch from active to passive behavior in the face of an acute stressor, aligned to cognitive functions underlying behavioral adaptation and survival.

Keywords: Depression; Forced swim test; Glucocorticoids; Mouse; Rat; Stress.

MeSH terms

  • Animals
  • Behavior, Animal / physiology*
  • Depression / physiopathology*
  • Depression / psychology
  • Depressive Disorder / physiopathology*
  • Depressive Disorder / psychology
  • Disease Models, Animal*
  • Stress, Psychological / physiopathology
  • Stress, Psychological / psychology
  • Swimming / psychology