School of Natural Sciences and Psychology , Liverpool John Moores University , Byrom Street, Liverpool L3 3AF, UK.
R Soc Open Sci. 2015 Jul 29;2(7):140399. doi: 10.1098/rsos.140399. eCollection 2015 Jul.
Recent developments in the study of animal cognition and emotion have resulted in the 'judgement bias' model of animal welfare. Judgement biases describe the way in which changes in affective state are characterized by changes in information processing. In humans, anxiety and depression are characterized by increased expectation of negative events and negative interpretation of ambiguous information. Positive wellbeing is associated with enhanced expectation of positive outcomes and more positive interpretation of ambiguous information. Mood-congruent judgement biases for ambiguous information have been demonstrated in a range of animal species, with large variation in the way tests are administered and in the robustness of analyses. We highlight and address some issues using a laboratory species not previously tested: the Syrian hamster (Mesocricetus auratus). Hamsters were tested using a spatial judgement go/no-go task in enriched and unenriched housing. We included a number of controls and additional behavioural tests and applied a robust analytical approach using linear mixed effects models. Hamsters approached the ambiguous cues significantly more often when enriched than unenriched. There was no effect of enrichment on responses to the middle cue. We discuss these findings in light of mechanisms underlying processing cues to reward, punishment and true ambiguity, and the implications for the welfare of laboratory hamsters.
近年来，动物认知和情感研究的进展催生了动物福利的“判断偏差”模型。判断偏差描述了情感状态变化的特征，即信息处理的变化。在人类中，焦虑和抑郁的特征是对负面事件的预期增加和对模棱两可信息的负面解释。积极的幸福感与对积极结果的预期增强和对模棱两可信息的更积极解释有关。在一系列动物物种中，已经证明了对模棱两可信息的情绪一致的判断偏差，并且在测试的实施方式和分析的稳健性方面存在很大差异。我们使用以前未经过测试的实验室物种——叙利亚仓鼠（Mesocricetus auratus）来强调和解决一些问题。仓鼠在丰富和非丰富的环境中使用空间判断 Go/No-Go 任务进行测试。我们包括了一些对照和额外的行为测试，并使用线性混合效应模型进行了稳健的分析方法。与非丰富环境相比，仓鼠在丰富环境中接近模棱两可线索的频率明显更高。丰富环境对中间线索的反应没有影响。我们根据处理奖励、惩罚和真正模棱两可线索的机制以及对实验室仓鼠福利的影响来讨论这些发现。
