Scopolamine increases perseveration in mice subjected to the detour test
INTRODUCTION: Perseveration is defined as a tendency to respond persistently to a particular stimulus, even after the response has become inappropriate. Increased perseveration is associated with aging in humans and leads to impaired ability to cope with problems. Aging is also associated with progressing dysfunction of cholinergic system, which is associated with various cognitive processes. AIM(S): Therefore, we tested an effect of anticholinergic drug on the level of perseveration in mice subjected to the water escape detour test. METHOD(S): Animals were first trained to use a visible platform and next were injected with saline or scopolamine (1 or 5 mg/kg, i.p.). Thirty minutes after the injection mice were tested with transparent barrier separating them from the escape platform. RESULTS: During initial detour trials all mice displayed behavior characterized by persistent returning to the place located in front of the transparent barrier. In control animals, this behavior was gradually replaced by swimming around the barrier. In contrast, mice treated with scopolamine continued to repeat the pattern of swimming toward the central part of transparent barrier separating them from the platform. This perseverative behavior was dose dependent and was significant at the end of detour training. CONCLUSIONS: These data show that dysfunction of cholinergic system leads to increased perseveration. FINANCIAL SUPPORT: Funded by KNOW (Leading National Research Centre) Scientific Consortium “Healthy Animal – Safe Food”, decision of Ministry of Science and Higher Education No. 05-1/KNOW2/2015.