The use of preferred social stimuli as rewards for rhesus macaques in behavioural neuroscience

Macaques are often motivated to perform in neuroscientific experiments by implementing fluid restriction protocols. Daily access to water is controlled and the monkeys are rewarded with droplets of fluid for performing correct trials in the laboratory. Although these protocols are widely used and highly effective, it is important from a 3Rs perspective to investigate refinements that may help to lessen the severity of the fluid restriction applied. We assessed the use of social stimuli (images of conspecifics) as rewards for four rhesus macaques performing simple cognitive tasks. We found that individual preferences for images of male faces, female perinea and control stimuli could be identified in each monkey. However, using preferred images did not translate into effective motivators on a trial-by-trial basis: animals preferred fluid rewards, even when fluid restriction was relaxed. There was no difference in the monkeys’ performance of a task when using greyscale versus colour images...

在神经科学实验中，研究者通常通过实施饮水限制规程（fluid restriction protocols）来驱动猕猴完成实验任务。实验人员会控制猕猴每日的饮水摄入量，并以液滴作为奖励，犒赏在实验室中完成正确试次的猕猴。尽管此类规程应用广泛且效果显著，但从3R原则（3Rs）的视角出发，探究可缓解施加的饮水限制严苛程度的优化方案仍具有重要意义。本研究针对4只参与简单认知任务的恒河猴（rhesus macaques），评估了以社会刺激物——同种个体图像（conspecifics）——作为奖励的可行性。研究结果显示，每只猕猴均表现出对雄性面部图像、雌性会阴图像以及对照刺激物的个体偏好。然而，在逐试次的层面上，被偏好的图像并未转化为有效的激励手段：即便放宽饮水限制，猕猴仍更青睐液体奖励。当使用灰度图像（greyscale）与彩色图像（colour images）时，猕猴的任务完成表现并无显著差异……