"I have come to find out what it's like to be dumb."

They really don't know what causes anxiety, or clinical depression. The are having a horrid time finding the true cause of these ailments. If anyone is seeing a MD who claims to know what causes depression and anxiety see someone else. It gotten so disappointing in the research community; very few companies are actively even looking for the root cause to these horrid diseases. So many people took these tri, and hetrocyclic drugs for depression, and if they worked--it was most likely placebo. Yes--panic attacks, and generalized anxiety respond to benzodiazepines most of the time, but hey are addictive, and no researcher who is smart would Not claim to know how they work. I wish you well.

I truly believe the best medicine is knowing you are going to get better. The placebo effect is sometimes stronger than any antibiotic. I sometimes believe the placebo effect is the only verifiable existence of God? When I am sick, I do a little research on the Internet, but have found it's better to just believe the medicine will work. Oh yea, I try to chose my doctors well--Board Certified who actually tried to keep current after years of practice.

I feel like I've become significantly less intelligent over time, and I can't figure out if that's really the case, or if it's a different issue that simply makes me feel less intelligent.

When I was in high school, everything I learned was simple -- everything was a piece of cake. I would program my TI calculator (with a list of assembly opcodes next to me) at the back of the class and basically ignore the lesson and then get the highest grade on every test. Same in chemistry. Every standardized test I took (SAT, ACT, etc.) gave results in the 99th percentile. Same with the AMC and AIME. I graduated 1/200 in my class. I had all kinds of interesting programming projects in my free time from age 12 to 18.

Then I went to college: a STEM school. The first semester went fine; I got all A's. The second semester, I got my first B ever. The third semester, more B's. Eventually a C. My final GPA ended up being 3.5, significantly lower than anything I had been used to. I couldn't stay awake during lessons in class. I was sleepy all the time despite getting good sleep (8-9 hours) every night. I never skipped class, but I may as well have considering how sleepy and groggy as I was. This had never been an issue in high school. I don't ever remember getting sleepy in class then, even if the lecture was boring.

Suddenly, new subjects became incomprehensible. The ease at which I previously absorbed new material was gone. Nothing "clicked" anymore. I'm in graduate school now and still nothing "clicks". I attend department seminars where visiting professors present their research, and it may as well be alien gibberish. I feel like I'm just faking my way through grad school at this point. I can still manage A's and B's in classes without ever understanding the content only because of the way the grading system's designed. Luckily, I seemed to have retained my programming capabilities.

I can't figure out what caused this. One option is physical: perhaps something chemically changed within my brain. Virus, physical trauma, getting older? No idea really. The other option is environmental. In high school I only had dial-up internet access, so anything I wanted to download, I had to really want. It was an all-day ordeal to get a 3 MB file. It was almost impossible to goof off online. Nowadays I get on the internet and just get distracted. I can't get into side-projects like I used to be able to. I still have the strong desire that I used to, but not the motivation. I don't know where it went; why would my personality just change for the worse like that? I almost wonder if skimming huge amounts of information online has somehow re-trained my brain to not absorb knowledge anymore.

Has this happened to anyone else? Have you figured out a way to reverse the process? I would love more than anything to have the incredible clarity with which I used to understand new subjects rather than this fuzzy, muddy feeling with everything I try to learn.

True in spirit, but untrue definitionally. The thing is, the psychiatric profession still basically subscribes to a Behaviorist theory of mind when it comes to treating neurological problems. There's no consideration of what's going on in your head when you have a neurological malady; your head is a black box, where drugs go in, and altered behaviors sometimes come out. "Clinical depression" isn't the name of a specific thing that we know goes on in the brain (in fact, it seems to be a whole cluster of things); rather, clinical depression is "the thing which taking an SSRI usually makes lessen." When a psychiatrist says you may be clinically depressed, what they're really saying is, "you have symptoms that may be manageable by the effects of this or that drug." They have no idea whether they're treating the root cause, or just masking it, and a lot of them don't care. They just want to see your behavior alter, like a rat given a swim test.

And really, thinking of things like SSRIs as "medicine" is part of the problem. SSRIs and the like are crutches--given to you to lessen the symptoms of a problem enough for it to stop being overwhelming, so that you can actually manage to make it to the CBT-practicing therapist every day, have the energy to find the the better job to get away from your horrible boss, etc. I wrote more on this here: https://news.ycombinator.com/item?id=6347620

(P.S.: In this case, though, if I might be a bit more pedantic: I didn't say that all those maladies in my post were caused by those imbalances. I said that inducing those imbalances, in the way that Lyme disease does, will mimic the symptoms of those maladies. Clinical depression may not be "just" a serotonin imbalance--but inducing "just" a serotonin imbalance tends to produce the symptoms of clinical depression. ;)

(P.P.S.: note that I never used the word "disease" or "illness" once. See my link above--these words don't apply to things like nearsightedness, so they don't really apply to the kind of problems neurological imbalances manifest as, either.)