Reward and immunocompetence

报偿性脑刺激的免疫调节作用具有重要的功能意义，适用于包括抑郁症和其他压力相关疾病在内的几种中枢疾病。例如，最近有研究表明，对某些大脑结构施加刺激，可以减轻那些对传统治疗没有反应的人的抑郁症状。了解奖励和免疫过程之间关系的基本性质是开发这种新疗法的基础。由于环境富集，也观察到保护作用，但很少有关于其免疫和内分泌影响的数据。在我们的研究中，由于内毒素攻击导致的疾病行为的表达根据组的指定而不同，在接受有益的脑刺激的动物没有表现出疾病行为，大约一半的动物在环境富集条件下表现出疾病行为，而对照组的所有动物都表现出疾病行为。与脑刺激奖励不同的是，脑刺激奖励的阈值表明刺激的奖励价值，但没有浓缩指数来评估个体动物对其环境的反应。例如，对于处于从属地位的动物，群体经历可能不如处于优势地位的动物令人满意，并影响免疫能力。这项建议的长期目标是纳入诸如年龄、遗传和性别差异等变量，以确定这些因素对免疫能力的贡献。大多数使用动物模型的研究没有按性别分层，尽管众所周知，适应性免疫和先天免疫存在性别差异。鉴于我们对研究与女性相关的独特免疫和内分泌特征的影响的普遍兴趣，我们的研究将扩大到包括女性和男性群体。

The immunomodulatory effects of rewarding brain stimulation have important functional implications applicable to several central conditions including depression and other stress-related disorders. For example, it has recently been shown that brain stimulation applied to certain structures reduces the depressive symptoms in humans who do not respond to traditional forms of treatment. Understanding the fundamental nature of the relationship between reward and immunological processes is basic to the development of such novel therapies. Protective effects have also been observed as a consequence of environmental enrichment, but there is little data related to its immunological and endocrine influences. In our studies, the expression of sickness behaviours as a consequence of endotoxin challenge differs according to group designation in that animals receiving rewarding brain stimulation display no illness behaviours, roughly half of the animals in the environmental enrichment condition display illness behaviours, and all animals in the control group display illness behaviours. Unlike brain stimulation reward, in which thresholds indicate the rewarding value of the stimulation, there is no index of enrichment to evaluate individual animal responses to their environment. For animals in subordinate positions, for example, the group experience may be less satisfying than for animals in more dominant positions, and affect immunocompetence. The long-term goals of this proposal are to include variables such as age, genetic, and sex differences to determine the contribution of these factors to immunocompetency. Most studies using animal models do not stratify by sex, although it is well-known that there are sex differences in adaptive and innate immunity. Given our general interest in examining the influence of the unique immunological and endocrine profiles associated with females, our studies will be expanded to include both female and male groups.