
Image of an A-beta peptide fibril produced by a transmission electron microscope.
(Carsten Sachse, Marcus Faendrich, Nikolaus Grigorieff/National Academy of Sciences)
In 1998, he was sixty-six and often seemed lost in thought. He told me, “I’m making more mistakes. You point them out to me. I’m not objecting to the fact that you do that, but it depresses me. As I get older, I’ll be making more mistakes.”
Age had begun to shade his temples and further sculpt his well-formed skull. What I couldn’t see were the microscopic lesions caused by abnormal proteins or by small strokes—either of which could have been silently compromising his brain.
What created those lesions? How could I know? I couldn’t use my senses to see or hear or touch those silent shape-shifters hidden inside the boney shield of his cranium.
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The lack of answers didn’t stop me from searching for explanations. I confess that I desired at least an illusion of control over my husband’s disease.
I read that the diseased brain is often characterized by abnormal protein fragments—neurofibrillary tangles of tau protein inside nerve cells and the beta-amyloid protein clumps outside of them. Although researchers consider both tau tangles and amyloid plaques to contribute to the degradation of nerve cells in the brain, the relationship between the two is little understood.
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In 2008, while waiting at the clinic with Dick I paged through an issue of Discover magazine. A large, 3-D image of an amyloid-beta (A-beta) peptide fibril—the type of protein fragment that accumulates in the brain as plaques—caught my eye. Shaped like a shuttlecock, black, with a red and yellow flare at one end, it propelled itself across the page. I tore the page out and tucked it into my purse.
When I looked at it later, I was dumbstruck. What initially appeared benign now seemed sinister. Leech-black, the slimy shape narrows, twists, and then splits, like a cobra’s tongue. The fibril seems to fly, sans wings, sans feathers.
The idea of a bat flitted into my mind, although the fibril isn’t shaped like one. Something about the fibril’s blackness, its silent flight, reminded me of being stirred from sleep by the rustling of a bat as it hurtled through our log home, mouth open, teeth bared. The double-natured bat—part bird, part rat—evoked fear in me. Did fears wing their way through Dick’s mind, too, as unease about his mistakes mounted?
Anne-Marie Erickson