Effects of Level of Acoustic Stimulation on Locomotor Activity in the Gerbil

Abstract

Two experiments dealt with the behavioral responsiveness of the Mongolian gerbil to the onset, offset, and intensity of auditory stimulation. In Experiment I, the presence of background noise, relative to a condition of silence, was found to facilitate rate of shuttle activity in the gerbil. Also, both incremental and decremental shifts in noise intensity produced immediate increases and decreases, respectively, in activity level. Experiment II revealed that the relationship between shuttle-activity level and background noise intensity was nonmonotonic over the 60-90 dB range, with optimal facilitation manifested at 80 dB SPL. A similar trend was observed with running-wheel activity. Finally, in both experiments substantial habituation of general activity was obtained. The results were discussed in terms of theoretical conceptions of the energizing properties of environmental stimulation (e.g. , arousal theory, stimulus intensity dynamism) and psycho-physiological reactions of the gerbil to auditory stimulation.