title: A matter of timing: harm reduction in learned helplessness.
abstract: BACKGROUND
  Learned helplessness has excellent validity as an animal model for depression, but problems in reproducibility limit its use and the high degree of stress involved in the paradigm raises ethical concerns. We therefore aimed to identify which and how many trials of the learned helplessness paradigm are necessary to distinguish between helpless and non-helpless rats.
  
  
  RESULTS
  A trial-by-trial reanalysis of tests from 163 rats with congenital learned helplessness or congenital non-learned helplessness and comparison of 82 rats exposed to inescapable shock with 38 shock-controls revealed that neither the first test trials, when rats showed unspecific hyperlocomotion, nor trials of the last third of the test, when almost all animals responded quickly to the stressor, contributed to sensitivity and specificity of the test. Considering only trials 3-10 improved the classification of helpless and non-helpless rats.
  
  
  CONCLUSIONS
  The refined analysis allows abbreviation of the test for learned helplessness from 15 trials to 10 trials thereby reducing pain and stress of the experimental animals without losing statistical power.
authors.forename: Sophie Helene
authors.initials: SH
authors.lastname: Richter
authors.forename: Alexander
authors.initials: A
authors.lastname: Sartorius
authors.forename: Peter
authors.initials: P
authors.lastname: Gass
authors.affiliation: Animal Models in Psychiatry, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, 68159 Mannheim, Germany. barbara.vollmayr@zi-mannheim.de.
authors.forename: Barbara
authors.initials: B
authors.lastname: Vollmayr
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003627:Data Interpretation, Statistical; D040261:Harm Reduction / Q000502:physiology*; D006380:Helplessness, Learned; D012372:ROC Curve; D051381:Rats; D017207:Rats, Sprague-Dawley