Cardiovascular responses in anticipation of changes in posture and locomotion.

Measurements were made in 29 adult baboons that were housed in social groups, allowing the occurrence of the full range of species-specific behavioral interactions. The cardiovascular variables measured included blood pressure, heart rate, renal blood flow, lower limb blood flow, and occasionally mesenteric blood flow. The data were telemetered from backpacks worn by the animals and were recorded in analogue form on a polygraph, digitally on a computer and were also recorded on the audio channels of videotape being made of the behavior and social interactions of the baboons. The video and the computer recordings were synchronized by a timing system that made it possible to relate the cardiovascular responses to the behavioral responses. A numerically based behavioral code was developed that allowed the categorization of the totality of the behavior, including postural and locomotor changes. Comparisons between baseline cardiovascular values and those occurring 1 s before the initiation of a movement or posture change gave no evidence of anticipatory cardiovascular responses unless the movement was associated with behavior that included emotional content. Hypothalamic perifornical lesions reduced or eliminated these anticipatory changes.