Cortical GABA and emotional processing in young people at risk of depression

临床抑郁症是一种常见的，通常是终身的疾病，给患者和他们的家人带来很大的痛苦和丧失能力。虽然对抑郁症有一些有用的治疗方法，但最好是在疾病的早期阶段设计干预措施，以防止抑郁症成为慢性和致残。为此，我们首先需要更多地了解使人们容易患上复发性抑郁症的因素。我们利用一种叫做磁共振成像的大脑成像新方法在这一领域取得了一些进展，磁共振成像可以通过使用强磁场来测量大脑的化学和功能活动。例如，我们发现，从抑郁症中恢复过来的人，他们的大脑对可怕的面部表情的反应仍然很夸张，而且他们的大脑中一种重要的化学信使GABA的水平也降低了。然而，我们不知道这些变化是早于抑郁症的发病，还是抑郁症及其治疗的结果。目前的研究旨在通过对年轻人（16-19岁）进行同样的调查来回答这个问题，这些年轻人本身没有抑郁症，但由于父母患有抑郁症，他们患抑郁症的风险增加了。磁共振成像被认为是安全和无创的，因此适合用于年轻人的研究。如果我们发现有抑郁风险的年轻人大脑中GABA水平较低，大脑对可怕的面部表情的反应增加，这将意味着这些变化可能是导致抑郁症发展的重要因素。然后，我们计划找到能够解决这些变化的治疗方法，希望我们能够预防或至少降低随后发生临床抑郁症的风险。

Clinical depression is a common and often a life-long condition that causes much distress and incapacity for sufferers and their families. Although there are some helpful treatments for depression it would be better to design interventions that could act at an early stage of the illness to prevent depression becoming chronic and disabling. For this we need to understand more about the factors that make people vulnerable to recurrent depression in the first place.We have made some progress in this area by taking advantage of a new method of brain imaging called magnetic resonance imaging, which can measure the chemistry and functional activity of the brain by using strong magnetic fields. We have found for example, that people recovered from depression continue to have exaggerated responses in the brain to fearful facial expressions and that they have lowered levels of an important brain chemical messenger called GABA. However, we do not know if these changes pre-date the onset of the depressive illness or instead might be a consequence of the depression and its treatment. The present study aims to answer this question by carrying out the same investigations in young people (aged 16-19 years) who have not been depressed themselves but who are at increased risk of depression through having a parent with depression. Magnetic resonance imaging lends itself to studies in young people because it is regarded as safe and non-invasive. If we find that young people at risk of depression have low brain GABA levels and increased brain responses to fearful facial expressions it will mean that these changes might be important in predisposing to the development of depression. We would then plan to find treatments that could resolve these changes in the hope that we might be able prevent or at least lower the risk of clinical depression occurring subsequently.