Depression is an emotional state that always retards the mind to varying degrees and leaves the depressed individual constantly exhausted and unable to manifest any positive thoughts or positive emotions.
Depression dampens all cognitive faculties anywhere from a fair degree to a degree that results in a temporary loss of intelligence and fluctuations in IQ would easily show this. From a neuroscientific perspective and from the imaging by functional MRI scans, the depressed brain is colored in the purples and blues that represent a nearly complete lack of neural activity.
It is as if the brain has become nearly frozen and static. Thinking itself, the capacity to represent ideas in consciousness and move from one thought to another, becomes a chore.
The memory gets fuzzy and the depressed individual's abilities of recollection and memorization become anything from flawed and slow to nearly completely hindered by the slowness and reduction in neural communication. Electrical activity fizzles out in the downward slope towards more depressed states.
Thoughts of suicide can rise to the surface as a possible remedy to the horrible and hard to endure emotional state. As someone who has been rather severely bipolar (or manic-depressive) for more than a decade, the thought of suicide in the bottom trough of the worst depressed states has always been a strangely and disturbingly comforting mental representation that plays over and over. It is not that I intend to kill myself but that I know there is at least one path away from the hellish paralysis of deep depressions.
Depression is crawling skin and social awkwardness to a level that often manifests in a complete lack of understanding of how to act, what to say, or even how to show facial expressions in the company of other human beings.
It is as if the mental fog of depression leaves one at a loss for ways of being that were before so simple and innately understood in better moods, that the absence of this knowledge, like social norms in social interaction, only serves to make the situation that much worse and serves to lessen the depressed person's self-image as now a broken alien who doesn't belong.
Alienation is a common side-effect of depression and it can be at least alienation from friends and family and at most alienation from one's own self that was, before the depressed state, someone completely different in that the former self was normal, capable, and, at least to some relative degree, happy or contented.
Depression leaves the depressed individual in a state of lethargy and disinterest in anything other than whatever will lead to not being depressed; be it medication, sleep, or time.
Suicide creeps into one's consciousness here as an undesirable yet apparent method of potential escape. Perhaps death is not such an escape and all beliefs about this amount to grand assumptions no matter what the basis is for such beliefs- be they beliefs that the world after death is an infinite nothingness or beliefs that we go somewhere else that is where we are karmically determined to go. The emotion of depression is like a cold, itchy, thorny blanket that one can not throw off at will.
Medication can certainly help though many people are unresponsive to some or all of the available psychotropic substances that can be used to treat either unipolar or bipolar depression.
Electrical stimulation in various forms from intense shock therapy to subtle electrical pacemakers for the brain seem to work for some of the most difficult cases of prolonged and abyssal depression but the side effects of the more intense shock therapies, such as ECT, are very difficult to deal with as they include loss of long periods of memory and the painful experience of being basically electrocuted at the temples, over and over, for perhaps a dozen or more sessions over a period of time determined by a psychiatrist.
No one who is aware of a past depressed state would chose to be depressed and it is one of the lowest emotional states on the spectrum or range of emotional possibilities for a human being. Depression is one form of hell and everyone who is in hell will seek a way out at all times and with high costs willing to be paid in order to find freedom from the chains of this emotional chasm.
