Similar tests of anxiety-like behavior yield different results: comparison of the open field and free exploratory rodent procedures.

Pharmacological agents that treat anxiety disorders are often validated in animal models prior to clinical trials. Yet results suggest little consistency in rodent anxiety-like behavior across tests. The current study examined the relationship between anxiety-like behaviors of male rats in the open field test and free exploratory paradigm. Results indicate most anxiety-like behaviors between tests were not correlated and few correlations existed within tests, despite similarity in testing apparatus, procedures, and quantified behaviors. These results suggest even very similar tests may provide insight into different facets of anxiety and urge caution when translating animal results to the human condition.