Hippocampal mossy fibres: implication in novelty reactions or in anxiety behaviours?

Hippocampal mossy fibre distribution is known to correlate with various processes including responses to novelty. Unfortunately, these correlations have been calculated using behavioural variables recorded in situations including anxiogenic components and so it is not clear whether the hippocampal trait is related to novelty reactions or to anxiety. In order to better elucidate the functional role of the supra- (SP-MF), intra-infra-(IIP-MF) and dentate gyrus (CA4) mossy fibres synaptic area, we investigated their covariations with behavioural measures recorded in situations related to novelty (free exploration test, confrontation with a novel object) or to anxiety (light/dark choice test). The hippocampus-behaviour correlation matrix reveals that IIP-MF and SP-MF correlate with variables linked to novelty reactions while CA4 correlates with measures related to anxiety.