One thing I don't understand is how a brain-state can ever be considered abnormal. It can be considered disadvantageous, or advantageous in some aspects only, but in no way be "normal". What are the normal facial features?
A "healthy" mind in a dysfunctional environment can produce physical symptoms that mimic mental illness---anxiety for example---which makes diagnosis difficult, and is the root of the difference between the blues and clinical depression.
Im not sure I understand. When you say "mimic mental illness", are you saying that environmental factors cannot cause a "healthy" mind to get a "real" mental illness?
But to my mind, no. The problems of a healthy mind in an unhealthy environment are easy to solve: change the environment and the problem goes away. On the other hand, problems such as my depression get only temporary relief from changing the environment; the only long term relief has been drug treatment.
Furthermore not all mental conditions are illnesses.
http://www.mayoclinic.org/diseases-conditions/mental-illness...
"A mental disorder, also called a mental illness or psychiatric disorder, is a [...] behavioral or mental pattern that may cause suffering or a poor ability to function in life. Such features may be persistent, relapsing and remitting, or occur as a single episode. Many disorders have been described, with signs and symptoms that vary widely between specific disorders."