Horizontal and vertical exploration in woodlice: A dual-process model.

Woodlice placed in an unknown experimental enclosure typically run (horizontal exploration) and rear up on the enclosure's walls (vertical exploration). Previous findings with Porcellio scaber indicate that these two behaviors have an opposite temporal distribution and show differential sensitivity to rotation-induced physiological stress. It is argued that the dual-process theory of habituation and sensitization can serve as a basis to account for horizontal and vertical exploratory activities in woodlice. A model is presented. This model could help identify individual variability in "temperament" and to isolate its effects in various behavioral tasks in woodlice and perhaps other invertebrate species.