Impaired neural responses to the sight and taste of chocolate: A model of anhedonia in depression.

临床抑郁症是一种常见的疾病，通常在成年早期开始，可能在一生中复发。临床抑郁症的复发性，加上它给患者及其家庭带来的负担，使这种情况成为痛苦和残疾的主要医疗原因之一。不幸的是，抑郁症的药物治疗只有适度的帮助，尽管现代抗抑郁药物治疗相对安全，但它们并不比50多年前偶然发现的原始抗抑郁药物更有效。发现更好的抑郁症治疗方法的主要障碍之一是缺乏良好的人类模型。本研究的目的是建立一个模型的基础上抑郁症的一个共同症状，即快感缺乏。快感缺失意味着失去人们通常喜欢的东西的乐趣，被认为是由参与愉快体验的奖励效应的大脑通路功能受损引起的。这些通路已经在健康人群中进行了很好的研究，使用一种名为？功能磁共振成像这是非侵入性的，如果小心使用，非常安全。我们发现，有抑郁风险的人，通过个人病史，当他们看到或吃或看到巧克力时，这些大脑通路的反应会降低，这表明奖励通路对巧克力的反应受损可能是抑郁症的一个很好的模型。本研究的目的是通过研究另一组抑郁症高危人群来建立这一想法，并观察某些抗抑郁药物是否会像模型预测的那样增加愉快体验的奖励效应。如果这些研究是成功的，这可能意味着我们的模型可能有助于开发治疗抑郁症的新药，也可能有助于识别可能导致抑郁症的药物副作用

Clinical depression is a common illness, often beginning in early adulthood, which can recur throughout a lifetime. The recurrent nature of clinical depression, together with the burden it places on patients and their families, makes this condition one of leading medical causes of suffering and disability. Unfortunately the medical treatment of depression is only modestly helpful and although modern antidepressant drug therapies are relatively safe they are no more effective than original antidepressant drugs discovered by chance over 50 years ago. One of the major stumbling blocks to discovering better treatments for depression is the lack of good human models of the condition. The aim of the present study is to develop a model based on a common symptom of depression, that of anhedonia. Anhedonia means loss of pleasure in things the person usually enjoys and is thought to be caused by impaired functioning of the brain pathways involved in the rewarding effects of pleasant experiences. These pathways have been well studied in healthy people using a form of magnetic brain imaging called ?fMRI? which is non-invasive and quite safe if used carefully. We have found that people at risk of depression, through a personal history of the illness, have lowered responses in these brain pathways when they see or eat or see chocolate which suggests that an impaired response of reward pathways to chocolate might be a good model of depression. The aim of the present study is to build on this idea by studying another group at high risk of depression and also to see whether certain antidepressant drugs increase the rewarding effects of pleasant experiences as would be predicted from the model. If these studies are successful it could mean that our model might be helpful in developing new drugs to treat depression and also perhaps in identifying drugs that might cause depression as side-effect