Then, 2 1/2 years ago, she had a stroke. It stole her ability to read, her ability to remember names, her right-sided vision. It also stole her depression.
Until the moment she had her stroke - a massive brain trauma to her left occipital lobe - Mum had been in a major depressive episode that had endured for two years, the longest stretch ever. Yet in the post-stroke rehab ward, I find her engaging with other patients in a way she has not done for years. She is animated - her speech, unlike her reading, quite unaffected by her brain injury - the antithesis of the lethargy that hamstrung her for so long.
Will it last, I ask her neuro as he makes his perfunctory rounds, striding through the ward, long-legged, angular, unsmiling. Nope, he says, adamantly and assuredly, with a finality I dare not argue with. He's the expert, after all. But I am disappointed. And afraid. Must Mum now learn to cope with her depressions without her books - her refuge when sick - since she seems unable to process written words?
Months pass, and Mum learns to navigate within the confines of her narrowed vision: She bumps into chairs less often, knocks fewer coffee mugs flying. She relearns to read a little. "I'm so slow," she says impatiently. We encourage friends and family to write her short, tight emails. Less overwhelming that way, I tell them. She even begins to tackle a book. But she doesn't learn to remember names. In fact, I notice, her memory loss is not limited to names of people and places. It is unreliable and potholed. Some memories hold fast, others have come quite adrift so that they vanish.
She gazes at the tablets I count into her pillbox. Tablets to sweep veins of clogging debris, tablets to keep her blood flowing, the two work to minimize stroke risk, I explain. "And what are these?" she wants to know, plucking a big red capsule from the tray. "Venlafaxine," I say, "for your depression."
But I don't have depression, she says, her eyes snapping up at me. She cannot be sure what she had for lunch yesterday, but she is quite certain she does not have depression. Never has. Today she knows she never had depression. Tomorrow she may remember a little of the illness that stole decades of her life away.
I am staggered. My mother has been on a cocktail of antidepressants and anti-anxieties for as long as I can remember. Sometimes they may as well have been crossed fingers, a rabbit's foot, a clove of garlic, for all the good they did, but to abandon them seemed reckless. My mother's illness was the knife edge upon which my father, my siblings and I all tiptoed. I grew to know it so well I could tell, by her appearance at breakfast, by how late she rose, by the tone of her voice whether depression was sneaking up on her again.
Six months after Mum's stroke and I notice a wobble. Her voice is teary, she lies in bed all day. I brace myself. Oh no, I think, how will we cope with this? On the third morning after the first tears, she is up and bright and smiling.
How are you? I ask nervously.
I'm fine, she says, cheerfully, in a tone that seems to say, "Why do you ask?," a tone that suggests nothing was ever wrong. "How are you?" she adds. My Old Sick Mum never had the energy to care how anybody else was.
Turns out, she was just having a bad day, a couple of bad days. My mum, who has never had a bad day in her life - she's only ever had months and months of them at a time. And now, 2 1/2 years after her stroke, she is happier than I recall seeing her in 40 years.
Where did the depressions go? She has never been depression-free this long. Was her neuro wrong?
I scour the internet for "depression-free post-stroke," but all I get are hit after hit of sites that describe the inevitable depression that seems to afflict stroke victims. Could it be, I ask Karen Postal, a clinical instructor of neuropsychology at Harvard Medical School and president of the American Academy of Clinical Neuropsychology, that the loss of memory means she can't hang on to her anxieties; she can no longer ruminate, gnaw on an old bone of worries ad nauseam?
This is possible, she agrees. But she is as confounded by my New Sick Well Mum as I am. Postal says she has seen patients with Alzheimer's whose families note they undergo a pleasant personality change, "they lose what may have been a difficult intensity, become oddly easier to live with." But she has never seen the same sort of personality change in a stroke victim. She takes time - hours, she says - to review the medical literature, she calls colleagues, but nobody has a definitive answer; there is no research to reference.
But, she reminds me, "depression is not just an emotional state, it's a thinking state, it's about habits of thinking" - translating, misconstruing, misreading, misunderstanding "and, yes, ruminating." So, if my mother's cognition was hijacked - for along with her right-sided vision loss and those proper nouns, her brilliant intellect is gone, and I must explain the simplest of things to her now, in the simplest of terms - that means her thinking habits, good and bad, have been derailed.
When the neuro in the post-stroke rehab ward told me, with such certainty, that Mum's brain injury would not oust her depression - "different part of the brain'' - I envisioned a century-old phrenologist's drawing mapping the topography of the mind, as if each cerebral slice correlates to a different mood or emotion or belief.
Our neurological knowledge today is much more refined and detailed. While so much of the brain is still a mystery, we do know it isn't the one-dimensional, segregated organ it was considered to be 100 years ago. "The more sophisticated we get in our research, the more we recognize that brain function is holistic, interconnected by highly complicated networks working together to produce what we label as mood, thinking, language," Postal says.
My mother's neural circuit board suffered a short. A fizz and a pop, the lights went out and the electricity had to be rewired. Her depressions vanished not, it seems, because of the part of the brain that was affected but because the cognitive routes her brain once took have had to deviate.
She thinks differently, so she is different. Different without depression.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)