As she locked eyes with it, the mountain lion moved forward, descending the shrubby bank and heading straight toward her.
Yellowtail waded back across the three-foot-deep stream, back toward her truck. To be prudent, she thought, she had better keep the width of the icy stream between herself and the animal. As she made it to the far side, the big cat quietly slipped into the water.
A former biology major, Yellowtail had studied predator behavior. She knew that if she began climbing the steep bank up toward her truck, she would expose her back, and she guessed that the moment of vulnerability might spur the mountain lion to attack. Instead she moved quickly down the edge of the stream and crossed again, feeling her way over the slick cobbles underfoot. Looking behind her, she expected to see the animal climb the far bank and disappear. But no: It followed her path along the water’s edge and again started swimming after her.
“I’m in trouble,” Yellowtail thought. “This is serious.” There was no doubting the mountain lion’s intention now. Trapped between the stream’s steep narrow banks, she couldn’t think of any way to keep the animal away. She was holding a microcassette recorder that she kept for taking notes, and she threw it at the cat. It just kept coming.
Yellowtail retreated down the riverbank, shouting and throwing rocks and chunks of ice. Somehow she managed to keep herself from running. She crossed the stream, worked farther down the bank, and crossed again. The cat followed, relentlessly closing the distance. Even as she felt panic building, Yellowtail had enough presence of mind to understand that what she was seeing was a classic example of predator behavior. Running would only stoke the animal’s attack instinct. She had to fight the urge.
The mountain lion was close now, near enough to pounce. As she splashed once more across the stream, the need to run surged over her like a shiver. She bolted, splashing madly through the shallow water, her legs churning over the rough, slippery cobbles of the streambed.
She ran with everything she had.
Yellowtail was now in the grip of the second phase of the fear response, flight. The sudden movement of the mountain lion had broken the spell of her attentive immobility and gotten her moving, but while the animal was still a fair distance off she had managed to keep her wits and suppress her fear centers’ automatic panic reaction. But as the cat drew closer, reason and willpower wavered as the fear grew stronger. At last they gave way altogether.
This process has been witnessed in the laboratory using brain-scan technology. Subjects inside an fMRI scanner were asked to play a Pacman-like game in which they were chased by a predator. When they were “caught,” they were given a series of mild electric shocks. While not exactly a realistic scenario, the game did elicit brain activity that paralleled Yellowtail’s. When the “predator” was far away, the subjects’ brains showed activity mostly in the prefrontal cortex. As it drew nearer, the area of greatest metabolism shifted to the periaqueductal gray, the region that codes for the behavioral patterns of the four fs.
Yellowtail made it only halfway across the creek before her rubber boot caught on a large rock. She stumbled, twisting, and went down hard into the water. At that instant the mountain lion pounced. Instinctively it lunged for Yellowtail’s neck, but as she fell it misjudged and dragged its teeth across her scalp. Under the weight of the big cat, Yellowtail slipped below the surface.
Looking back on the moment from years after the fact, Yellowtail can still recall every detail with perfect clarity. She remembers feeling the warmth of the animal’s mouth on her head. She remembers looking up toward the surface through her sunglasses and thinking, with a perplexing degree of calm: “When your time’s up, your time’s up.”
Yellowtail had entered a third phase of the fear response, a state known as tonic immobility, or quiescence—in lay terms, playing possum. When an animal is seized by an attacker, the caudal ventrolateral region of the PAG generates a response that from the outside looks like total collapse. In the teeth of a full-blown sympathetic response, the parasympathetic system now swings into overdrive. The body, insensitive to pain, goes completely limp, often falling to the ground as awkwardly as rag doll, limbs splayed, head thrown back. Eyes closed, it trembles, defecates, and lies still. It looks, in a word, dead.
This is the position of utter despair, a final, last-ditch Hail Mary pass of a strategy. The one hope of quiescence is that the attacker, thinking its quarry has expired, will stop attacking. In Yellowtail’s case, the mountain lion appeared to react to her quiescence. Momentarily it released its grip. That was enough. In an instant she snapped out of her dissociative dream state and was sputtering back up to the air. Without reason, without thought, she started running again, flailing so hard that she ran right out of one of her hip boots.
And then—nothing. Whatever happened next, Yellowtail has no idea, because for the next 10 or 15 seconds she was overcome by a panic so blind that she blacked out. She had entered a realm of fear strong enough to shut down the memory-forming hippocampus and perhaps even consciousness itself.
The science behind that kind of amnesia remains murky, because such intense fear is a state as yet inaccessible to science. It is known that amnesia often accompanies extremely terrifying experiences. Chances are, an overdose of cortisol or a related substance, corticosterone, disrupts the hippocampus and inhibits the formation of new memories. This could be beneficial if it prevents later traumatic recollections.
Yellowtail will never know what terror her amnesia cloaked. At any rate, it did not last long. The next thing she remembers, she was on the riverbank on the far side of the stream. She had emerged from her blind panic oddly collected and remembers that time seemed to be moving in slow motion. She found herself lying on top of the mountain lion’s shoulders, her right arm thrust down its throat. She looked down and saw that the animal’s jaws were so huge that its canines were overlapped on either side of her arm.
NEXT: THE SHOWDOWN