By Stu Whitley | Bio

No voice divine the storm allay'd,
No light propitious shone;
When snatch'd from all effectual aid,
We perish'd, each alone:
But I beneath a rougher sea,
And whelm'd in deeper gulphs than he
—William Cowper, The Castaway

There are probably more things at work in the human mind than we will ever know. Too often the turmoil we confront in our daily lives gets the better of us, and we succumb to a depressed state for a day, a month, or perhaps longer*. The above stanza brilliantly captures the sense of isolation, despair and torment in the mind of someone who is incapable of seeing the world with a balanced perspective. Cowper, who was not capable of being diagnosed as such in the 18th century, probably suffered from recurrent depression.

Science has unearthed a variety of potential causes for depression—from pesticides and thyroid conditions to lower counts of stress hormones (such as corticotrophin-releasing hormone), a higher body mass index (suggesting that fat and ‘jolly’ do not always go together) and sleep disorders. But the causes for the majority of instances where depression captures the imagination remain elusive. We do know that, equally, most of these cases are transitory, just as we know that, for sufferers, the night seems endless.

Much has been written about the condition, particularly by those who have experienced it. In 1936, F. Scott Fitzgerald published three essays about his spiritual depletion in Esquire, which he later consolidated in a larger work titled The Crack-Up. There he asserted that it takes great acumen to ponder conflicting truths without going mad. “The test of a first-rate intelligence is the ability to hold two opposed ideas in mind at the same time and still retain the ability to function.”

William Styron, author of Sophie’s Choice, wrote a short memoir of his own emotional descent called Darkness Visible (1989). Styron was not in favour of the term ‘depression’; he said it was “a true wimp of a word for such a major illness.”

Donald McCullough wrote a chronicle of his own battle with depression in The Wisdom of Pelicans (2002). In the aftermath of a scandal borne of an affair while he was married, he lost much of what sustained him, including his reputation for honourable conduct. He settled into a depression which eluded the best advice he could get. “I have lost much, and loss leads naturally to grief, and grief leads naturally to depression,” he wrote. “Emotions just are: they’re present whether you want them or not, unbidden, with an annoying will of their own.” Many others have written of the encompassing darkness, the blackness that overtakes the will. ‘Going through the motions’ is another way to express the despondency.

From a biological perspective, negative feelings, communications or perceptions release the hormones that are commonly associated with stress. Our brain’s autonomic responses, rooted in the limbic system, trigger which biochemicals are released. Current thinking on this subject is that low levels of “good” stress may cause beneficial changes. However, if continued for sustained periods, those stress hormones can actually cause damage to the brain.

The body possesses a feedback system for regulating the amount of cortisol in the bloodstream. The pituitary gland makes and secretes a hormone known as adrenocorticotropic hormone (ACTH). Secretion of ACTH signals the adrenal glands to increase cortisol production and secretion. The pituitary, in turn, receives signals from the hypothalamus in the form of the hormone CRH, or corticotrophin-releasing hormone, which signals the pituitary to release ACTH. Almost immediately after a stressful event, the levels of the regulatory hormones ACTH and CRH increase, causing an immediate rise in cortisol levels. When cortisol is present in adequate or excess amounts, a negative feedback alerts the pituitary gland and hypothalamus to reduce the output of ACTH and CRH in order to reduce cortisol secretion.

New research is examining a stress-related molecule called “corticotropin releasing factor” (CRF). CRF was initially thought to be a cue from the hypothalamus to the pituitary, which governs the brain’s hormone-releasing system, causing it to release ACTH , which in turn tells the adrenal cortex to release adrenalin (epinephrine). However, there are other sites in the brain that make and release CRF. CRF is not merely the medium from brain to body; it is central to the entire stress response within the brain prior to the discharge of adrenalin.

It appears that constant stress or worry can ruin the internal physiological mechanism that regulates our responses to stress. Damage to the brain seems to occur within the hippocampus, which appears to be vulnerable in two ways: first, stress may shrink it directly (probably by promoting cell death there), or by interfering with the brain’s normal stress-prevention/relieving capacities. These new discoveries make it more urgent to develop strategies to deal with depression that are not pharmacologically based or otherwise invasive.

Written by admin at Learning
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