And the blog author definitely is working from a position very critical of the use of psychopharmaceuticals. Persons with strong opinions often do become closed minded and biased in the way they interpret information.
Being open to critiques about chemical imbalance is probably important to collecting information to protect oneself against misuse/overuse of psychopharmaceuticals. But, being open to consider critiques doesn't at all require surrendering critical thinking about arguments made against the critique. Indeed, it's important to look at the strengths and weaknesses of that criticism... and thanks to you for commenting on several of them.
Here is something from a different source than Levine, although it's also not a professional science journal...Psychology Today
Let me share a yet to be published study by Dr. Brett Deacon and his colleagues. They recruited 91 adults who are clinically depressed or once was. To make this credible, he gave everyone a fake "Rapid Depression Test" that determined whether their serotonin levels were abnormally low compared to other neurotransmitters. To make this test seem legit, they swiped the inside of people's mouths with a cotton swab and the saliva was carefully moved to a sealed container to be taken to the lab for examination. Afterwards, everyone received detailed test results and a random half of participants were told that their serotonin levels were problematic and there is a clear chemical explanation for their depression. The other half were told their serotonin levels were normal and their depression cannot be purely explained by brain chemistry.
The big question: What happens to people when they buy in to a biomedical explanation for their depression?
The answer: Bad things. They become pessimistic that recovery is possible. They become less confident that they can manage and regulate negative moods that arise (and they always do). The notion that depression is their brain's fault does not lessen the stigma or self-blame one bit. And they no longer believe that psychotherapy is a credible or useful strategy for treating their depression and instead, are ready to be dispensed a pill cure. Essentially, they become less flexible in their options for treating depression and less confident that they will escape its clutches.
It is going to be tough to battle the science fiction promoted by pharmaceutical companies. What makes the challenge increasingly difficult is that these companies spent $57.5 billion to promote drugs in 2004, and the numbers are only getting bigger. If we care about reducing human suffering, it's time to bring on the noise and ensure that everyone knows the science. We are fortunate to have scientists that are willing to fight powerful companies and dominant beliefs in search for the truth.
http://www.psychologytoday.com/blog/curious/201403/what-causes-depression-myths-about-chemical-imbalances
I'm glad some people get benefits from atypical depressants