Chronic pain induces several cognitive deficits in human subjects, such as the incapability of performing correctly in decision-making tasks that have a risk component, such as rewards of variable value. This cognitive impairment is known to occur after amygdalar or orbitofrontal lesions, where individuals are incapable of long-term planning and take high-risk decisions even if they lead to overall losses. It was shown that chronic pain patients also present this pattern of impaired decision-making. However, no studies in chronic pain animal models have addressed poor performance in frontal-based cognitive tasks. We developed a novel behavioural task based on repetitive reward-based simple decisions, and studied its performance by monoarthritic and neuropathic chronic pain animals, chronically stressed animals and a control group. The task consisted on consecutive trials in which a rat entered an operant chamber and had to choose between two levers to recover food rewards of different size and probability. The pattern of preference in 90 consecutive choices was studied (high- or low-risk lever preference). Animals with chronic inflammatory or neuropathic pain showed preference for high-risk choices as well as increased persistence after high-risk choices in non-rewarded trials. In stark contrast, control and chronic stress animal models, displayed a preference for low-risk choices (p<0.05). These results show that chronic pain in the rat causes a deficit in a prefrontal-based neurobehavioral task. Moreover, we show that this impairment is not due to chronic stress, which raises the possibility of a direct effect of pain upon prefrontal neuronal populations.