文档介绍：***抑郁症 Insight into The Invisible Disease: Depression
电子科技大学生命科学与技术学院
2018/7/24
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Brenda's story:
"It was really hard to get out of bed in the morning. I just wanted to hide under the covers and not talk to anyone. I didn't feel much like eating and I lost a lot of weight. Nothing seemed fun anymore. I was tired all the time, yet I wasn't sleeping well at night. But I knew that I had to keep going because I've got kids and a job. It just felt so impossible, like nothing was going to change or get better.
Rob's story:
"Things in my life were going all right. I had just gotten my PHD and was starting a new job. My family was really proud of me. But inside, I was feeling terrible.
"At first I was feeling sad all the time, even though I had no reason to be. Then the sad-ness turned into anger, and I started having fights with my family and friends. I felt really bad about myself, like I wasn't good enough for anyone. It got so bad that I wished I would go to bed and never wake up.
Symptoms of depression
sad mood
loss of interest or pleasure in activities that were once enjoyed
change in appetite or weight
difficulty sleeping or oversleeping
physical slowing or agitation
energy loss
feelings of worthlessness or inappropriate guilt
difficulty thinking or concentrating
recurrent thoughts of death or suicide.
心理压力与HPA轴
在想象的片断中,我们触及到主管“战斗或者逃跑”的系统,正是它源源不断地将环境中的变化转化为我们所感知的心理压力的系统。
这个系统涉及到三个器官,下丘脑、垂体和肾上腺,我们将它们放在一起称为下丘脑—垂体—肾上腺皮质轴(HPA轴)。
HPA轴对我们身体的影响范围异常广泛,它一方面掌控着我们的情绪,同时还影响着循环呼吸等重要生理系统的状态。
我们的眼睛耳朵等感官,将外界环境信息源源不断的传送到大脑皮质的相关区域中,进行评判。
如果皮质认为存在某种威胁时(可以是现实的也可以是纯粹想象中的),就发送信息激活边缘系统中的杏仁核。
杏仁核则分泌CRH(促肾上腺皮质激素释放激素)刺激脑干以激活交感神经系统,受交感神经控制的肾上腺髓质将肾上腺素分泌到血液中。
血液中的肾上腺素改变了我们的呼吸和循环,同时也让我们的感官变得更加敏锐。
过度的惊恐和紧张常常导致过多的肾上腺素被释放,以至于发生难以控制的肌肉震颤或者肌肉完全松弛。
例如,有些人在参加高考时就曾因紧张过度而无法抓住钢笔,而某些人在惊恐过度时,常浑身瘫软,连保持站立都无法完成。
另外杏仁核还通过CRH激活脑垂体,促使其分泌ACTH(促肾上腺皮质激素),进入血液的ACTH则促使肾上腺的皮质释放相应的皮质激素,其中最主要的是皮质醇。
皮质激素的作用异常广泛,它对神经系统的影响颇为微妙,在适度的压力下,HPA轴导致少量的皮质醇分泌,激活大脑的奖赏中枢让我们产生欣快感,这就是我们都比较乐意尝试的“刺激”。
可以预料这个系统对动物而言至关重要