Link between emotional memory and anxiety states: a study by principal component analysis.

Numerous theoretical as well as pharmacological arguments lead to the assumption that anxiety and memory are two closely linked concepts. Nevertheless, the study of this relationship is full of complexities because neither memory nor anxiety are unitary phenomena. Indeed, the term memory covers a large number of concepts, and anxiety has been divided in two main classes, "state" and "trait" anxiety. Recently the neophobic responses exhibited by Balb/c mice confronted to the free exploratory paradigm have been proposed as a "trait anxiety" model while response exhibited in the light/dark choice procedure as a "state anxiety" one. The aim of this study was to further clarify the link between these two anxiety types and memory of emotional events assessed in the passive avoidance test. The relationship between the variables measured in these three tests were assessed by a principal component analysis that confirmed that the behavior recorded in the two anxiety tests does not reflect the same psychological state, and showed that emotional memory is linked to "state" but not "trait" anxiety.