Posts Tagged ‘cats’

The Virtue of Stiffness

June 1st, 2010 | Meera

I realize how determinedly morbid this is going to sound after telling you not three weeks ago that I am obsessed with death, but at 7 o’clock this morning I got down on my hands and knees in the bathroom to pull the stiffened body of a dead cat out from underneath my claw foot tub, and at 5 o’clock this evening those same two hands of mine drew the cranium and jaw bones of a raccoon, tenderly packed in bubble wrap and Styrofoam, from the recesses of a box that arrived in the mail.

But hey, sometimes that’s just the way your day turns out.

The expired cat was not, I hasten to add, my cat; if it had been I would be in no state to write these words. As it was I slept poorly last night, knowing the poor thing was just on the other side of the bedroom wall and likely close to death. My dreams were full of it. In life, the cat was a small, black, medium-haired beastie, with egg-yolk yellow eyes and a burbling purr (cats purr when stressed or traumatized, not just when content). In death, those eyes, I noticed, were open: their pupils—like those of human corpses—fixed and slightly dilated. When in its prime it was undoubtedly a pretty little thing.

Ross and I picked up the cat yesterday evening about two blocks from our apartment. It was drenched to the bone and without visible signs of injury, but moving slowly and with an almost drunken gracelessless very uncharacteristic of a feline. We thought it might have fallen out of a window or been hit by a car, and brought it into our home with the hope that the creature would survive the night and we could take it to the nearest vet as soon as it opened today—but sadly, our best efforts were in vain.

The cat had mustered what little strength it had in order to crawl underneath the tub before it died, probably because it felt a little safer in that narrow, constricted space. It was there in the morning when we went in to check on it, and if there had been any doubt about its expired status, a hand reached out to touch it made a definitive answer immediately apparent from two things: coolness and rigidity.

The average core body temperature of a cat is about three degrees higher than the average core body temperature of a human, or about 102°F. If a cat has ever sat on your lap, you already know this. A living cat is a thing of reliable warmth. Mine, for instance, is a blanket that provides snug comfort in winter and transforms into a heavy irritation in summer. This cat was cool, though not cold, to the touch.

someone's got to do it

In death, the systems that the body relies on to regulate its temperature start to fail.The rapid contraction and expansion of the muscles that produce a warming shiver can no longer take place; nor can the vasoconstriction (tightening of the blood vessels) that keeps heat from escaping from the skin, or the chemical reactions that can transform fat directly into heat in our cells. Cold as death, they say. I can tell you that what they say is true.

If I had had the means or the inclination (macabre even for me) to take its temperature, I might have been able to determine the approximate time at which this cat crossed the border between life and death. To do this I could have used the knowledge that the average mammalian corpse cools at a rate of about 1.5°F per hour, although it would have been difficult to come to a precise estimation. Algor mortis (Latin for “the coolness of death;” and death is, I fear, a cool customer) might have been affected by the size of the cat, the amount of insulation it carried on its slight frame, the ambient temperature in my bathroom and that of the tile on which it was resting, as well as other factors.

Still, a calculation could have been made. It is possible, for instance, that I could have somehow aligned the cat’s hour of death with one or another of the times in which it had wandered through my fitful sleep in the form of a dream-black-cat, healthy and mewling and full of vigor. If I were of a soul-believing bent, that might have been comforting.

But even if the cat had somehow managed to retain a good deal of its body heat after its death, the rigidity of its body would have told me it was gone, and had been for some hours. Rigor mortis (Latin for “the stiffness of death;” and death is, I fear, an inflexible wretch) is a tightening of the muscles that sets in in small mammals, like cats, within a couple of hours of the end. Apparently, the use of the term stiff to refer to a corpse dates back to the very beginning of the 13th century—so clearly has the phenomenon of rigor mortis been associated with death, and for so long.

What causes this stiffness is a sequence of chemical events that is, frankly, marvelous. (I think so, anyway.) Here’s how it goes. Normally, muscles contract because they’ve received a signal in the form of a nerve impulse from the brain. When that impulse reaches a muscle cell, it triggers the release of a neurotransmitter called acetylcholine. Acetylcholine plugs itself into receptors on the surface of the cell, opening channels through which sodium ions enter. The sodium, in turn, causes a flood of calcium ions to be released within the muscle cells. Finally, the calcium ions enable two kinds of muscle fibers—actin and myosin—to bind together and cause the muscle as a whole to contract. In order to release that contraction, an infusion of energy is required to push out the calcium ions and return the muscle fibers to their relaxed positions.

It’s all a beautifully rehearsed and executed electrochemical relay race that results in tight, or rigid muscles. (Want to set it in motion right now? Clench your fist. There. Nerve impulse—acetylcholine—sodium—calcium—actin/myosin—clench. If you squeeze your eyes tight, you can tell yourself that you almost feel those microscopic channels opening and closing. You’ll be lying, but it’s a beguiling notion.)

After death, accumulated calcium ions tend to leak across the cell membrane into muscle fibers, causing a contraction that cannot be released because the cell is no longer generating energy. And so: Stiff as a board, they say.

I can tell you that what they say is true. By the time we looked in on our sweet, unfortunate stray in the morning, its limbs had hardened to the point where it was difficult to draw from its hiding place. Ross had to kneel beside the tub and push gently on its back legs, while I pulled gently on the scruff of its neck, to get it out. If I had held the animal up by its torso, which I did not, its legs would not have hung loose and sweetly heavy like those of my living, breathing cat. They would have remained as they were: curled around its body like armor.

(If I had waited several more hours, though, loose they would have come. Rigor mortis dissipates as decomposition sets in, breaking down muscle tissue and releasing the contracted fibers.)

I could see, as he pushed and I pulled, that Ross was a little red-eyed and sniffly to see the creature in what must have seemed, to him, a strange and unnatural state. I, on the other hand, had grieved the night before. It was much more difficult for me to witness the cat as it was before death, its hot breath coming in and going out in ragged pants and its body so lacking in strength and nimbleness, as if it had forgotten how to move its four paws. Life, as the Buddha says, is suffering.

But this morning as I lifted the limbs that had once lent it the lucky poise of nine lives and felt how they had gone hard and inflexible, it was clear that the cat had ceased to be a suffering being and become, instead, a body. Its very stiffness protected me from pity, providing a hard, unassailable demarcation between life and death. For that I am rather grateful, because no matter how interested one is in death, it is no lovely thing to pick up the cadaver of something whose nose you stroked the night before. I am curious, not ghoulish. This cat’s death was both unnecessary and melancholy.

152

About my adoration for this raccoon skull, on the other hand, I have no excuses. A friend, knowing my predilections, offered to find it for me: and so it was found. And cleaned. And packaged. And sent. And the stiffness of its beautiful bones has a different sort of virtue.

On the How of the Purr

June 1st, 2009 | Meera

I don’t even have to touch her, sometimes, before it begins; on my approach, her ears unfold to my footfalls, each one a triangular flag hoisted by a tiny sailor. Chin lifts from crossed paws, emerald eyes widen, and I couldn’t stop it now if I tried—for even before my thumb has arrived at her furry head bearing its promised caress, the whole thing is underway. I can feel a tremor in her, radiating outward from a secret, central source. It hums gently through her spine as I lay my other hand on her back: a bubbling, burbling thing. A purr.

She has curled up on my lap now, become a mottled grey egg with no edges, and it seems as if the whole of her body vibrates as one well-oiled machine: but two fingers carefully tucked under her chin find the strongest buzz. Squinting, I can actually see it, just—pushing and pulling at her skin, tickling the hairs into a movement like the whisper of a summer breeze through tall grasses. The purr is a force that is insistent without being urgent, and I love it. I think, in fact, that I may be addicted to it. If worry clamps around my chest, look for me on the sofa, waking the cat from sweet sleep into indignation so I can set her in motion.

blissed out

Most forms of vocalization, including human speech and cats’ meows, are created by the vibration of the vocal cords as a column of air is pushed past them. The vocal cords are diaphanous membranes that stretch across the hollow organ—how richly it deserves that appellation—known as the larynx. The nature of the sounds we produce depends on how tightly the vocal cords are pulled by the muscles of the larynx; like a guitar string, the greater the tension, the higher the pitch. The whole apparatus is capable of bringing forth an astonishing cacophony of peals and murmurs, and we can learn to manipulate them with a high degree of control. The cat in our house, for instance, is a stylish songstress who expresses herself with all sorts of vocal experimentation: chirps, meows, yowls, growls. Her commentary on the world varies widely in pitch and form, and she is not above running through every pattern in her power in order to make herself understood.

Purring is different. Purring has almost the regularity of a metronome. In most domestic cats (Felis catus), it is generated by vibrations that take place at an incredibly consistent frequency—somewhere between 20 and 200Hz, or vibrations per second, according to data collected by animal behaviorist Elizabeth von Muggenthaler. (In order to get these results, Muggenthaler took tiny accelerometers, devices that are more commonly used to do things like detect a falling laptop and trigger shock control measures, and glued them temporarily to the skin of cats. Then, in what must be one of the most relaxing experimental setups ever conceived, she had her test subjects lie on blankets, where they were occasionally stroked.)

The soft buzzing coming from the bundle in my lap hardly ever jerks or hiccups—doesn’t much speed up, doesn’t much slow down. Even more miraculously, the hum of a cat continues and continues and continues, pausing only for brief, almost imperceptible moments as the air inside its lungs changes direction. Speech, no matter how soothing the words, is messy; ragged; broken by breath. Anxiety can breach its gaps. A purr, on the other hand— a purr stitches together inhalation and exhalation. Breathing in and breathing out become a single expanse of vibration. It’s the reason I enjoy folding over my cat, letting her whirring breath wrap around me like a smooth blanket of sound.

I find the comforting reliability of the purr marvelously contradictory in the light of how it is produced. In a way, what biologists believe is its basic mechanism (there is still some debate on the issue) relies on discontinuity. When a cat purrs, its vocal cords aren’t just being stretched. They’re actually being alternately pulled open and shut across the larynx, constantly interrupting the flow of air as it passes in both directions. First they let air through, then prevent its passage, like a gate whose doors swing back and forth at incredibly regular intervals. Each time this happens, a small, pressurized puff of air builds up, whose sudden release produces an audible sound.

jade

The reason the intervals between the gate’s opening and shutting are so regular, it seems, is that, like a heartbeat, they are governed by a timer. Somewhere in the brain of every cat is a pacemaker of sorts known as a neural oscillator. This is a neuron, or perhaps a small network of neurons, that—once activated—fires in a repetitive, periodic manner that is utterly predictable. In the case of the oscillator that controls purring, the purpose of this continued relay of synapses is to send signals to the laryngeal muscles, instructing them to tighten and relax in turn. As they do so, the tiny gate they control swings open and closed. The result of all these mechanisms working together is the beautiful, steady putt-putt-putt that brings me so much pleasure.

I wonder if you’ll understand when I tell you this: Knowing that the production of my cat’s purr relies on an automatic neurological process makes it even more dear to me. A cat is a creature of caprice, unpredictable and strange—my cat perhaps more so than any. If she herself shaped the rhythm of her purr, how could I rely on it for solace as I do?

Instead I imagine the purr’s musical hum existing in some deep, essential way that is not limited to her small frame—like the movement of the earth, like the tides. And as I hold her I think of this rhythm flowing through her into me, willing the timer in her brain to somehow speak to the muscles in my own throat.