Electrical stimulation of lateral hypothalamic area and behavioural sequences in a lacertid lizard

The observed transition frequencies of behaviour patterns were obtained for isolated lizards (Gallotia galloti), as well as those expected if the patterns were independent. The transitions differing significantly from random were calculated when: (1) the animals had an electrode in their lateral hypothalamic area (I); (2) they were electrically stimulated (S). The index O-E (O = observed transition frequency; E = expected one) was used to extract the statistical significance of the behaviour transitions. The Friedman and Wilcoxon tests, used to compare the relative transition frequencies between I, S and a first control (C) condition, showed that the main effects during the stimulation period were a decrease in the relative frequency of some transitions involving the climbing pattern and an increase in others including some exploration patterns.