Alex Brett

Morgan O'Brien Mysteries 2-Book Bundle


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travel up my spine. “Does he have access to confidential information?”

      “No. At least I don’t think so. I don’t even have access to the test solutions.”

      I started to respond with some platitude but realized that she wasn’t listening anyway. She had turned and was staring at the wall, running something over in her mind. I shrugged, picked up my briefcase, and started to get up. I didn’t know if she’d hear me, but I felt I should say it anyway.

      “I’m sorry about tonight, Elaine. Actually, I’m sorry about everything, but I am here if you need me.”

      She snapped back suddenly, and swung around. “He can’t know anything, Morgan. If he does, I’m screwed.”

      I kept my voice neutral. “What do you mean?”

      She thought for a minute, then fixed me with a level gaze. “This has to be confidential. I need your promise.”

      “You’ve got it, but only if it’s legal. If it’s not… “ I shook my head.

      She took a deep breath and laid her palms flat on the table. “By this time next year, I will have authored the most important paper in sensory physiology to be published in this decade. I’m this close.” She showed me an infinitesimal space between her thumb and forefinger.

      Coming from a lesser person the word delusion would have popped into my head, but in terms of research, Elaine’s feet were firmly planted on the ground. If she was saying she was on to something big, she was.

      “That’s fabulous. Are you publishing with Madden?” It was like I’d hit her with a cattle prod. She leapt up and brought her palms down on the table hard enough to make me jump. “It’s my research. My discovery. Madden’s fronting the money, that’s all.” Then she seemed to see me, remember who I was, and she sat back down in her chair, but her voice was still determined. “I run the research, I get the credit. I didn’t lie about Madden.”

      “You didn’t tell the truth either.” And given our relationship I was more than a little peeved. Still, maybe I owed Elaine something for breaking into her apartment. “Look, if you want me to take a peek in Graham’s office tonight…” I shrugged, “… since I’ll be in the neighbourhood.”

      I thought she might take the high moral road and object, but she didn’t. In fact, she didn’t even look surprised. Instead she said, “How much do you know about what I’m doing?”

      “Not much. Only what Dinah and Edwards have told me.”

      “And they don’t know, not the details. It had to be just Madden and me.” She sighed and sat back in her chair. “If you’re going into Graham’s office you have to know what to look for, so I better start at the beginning.”

      And she did. I took a chair beside her and she flipped over a piece a paper, pulled out a pencil, and began to sketch, her voice impatient and excited all at once.

      “You know that all sensory organs have receptors, right? And you know that the job of the receptor is to take information from the outside world and change it into something that the brain can process. So, receptors are triggered by external stimuli, and usually very specific stimuli.”

      I nodded. On her paper she’d drawn an eyeball in cross section with a line connecting it to something that looked vaguely like a human brain. She tapped the eyeball with her pencil. “Your retina, here, is made up of rod and cone cells.” She scribbled a dark black line at the back of the eyeball. “They’re the receptors. When light hits the membrane of a rod or a cone cell, a chemical change takes place at the membrane, and this initiates a whole sequence of events that result in a nerve that’s attached to the receptor being fired. The nerve impulse travels up a neural pathway,” she traced the line attaching the eye to the brain, “eventually arriving at a visual centre in the brain.” She drew a small circle on her schematic brain and initialled it VC. “The visual cortex, for example, consolidates all the information being sent from the eyes and interprets it as an image. But the thing I want you to remember is that each rod and cone cell are highly specific: each responds to only a narrow band in the spectrum of visible light. If light of other wavelengths hits the receptor, nothing happens. That’s why we see colour and detail.”

      She drew another schematic. To me it looked like some kind of maze, but like the eye, it was attached to the brain by a line. “The ear works basically the same way.” She saw my confused expression and shook her head in disgust. “That’s the inner ear, remember? Those are the canals and this,” she pointed to a little ball in the centre, “is the cochlea, roughly equivalent to the retina in the eye. But instead of rods and cones this thing contains hair cells, receptors that respond to the physical vibrations caused by sound.”

      She drew a little round ball with a hair poking out of it. “Like that.” She looked up. “I’m simplifying this, okay?”

      Since I hadn’t taken a course in sensory physiology since my undergraduate years, I didn’t mind at all. She went back to her drawing.

      “The important thing again is that each hair cell — each receptor — only responds to a narrow band of frequencies. The hair is literally pushed by the right frequency of sound,” she drew another little round ball with the hair bending over like a sapling in the wind, “and this mechanical stimulation triggers the sequence of chemical events that end with the nerve firing and a signal going to the brain. So what about the olfactory system?”

      Above the amorphous brain — which was now attached to an eyeball and an inner ear — she drew a big schnoz with a question mark hanging off its tip. I started to laugh, but caught her expression: serious and intent. It wasn’t meant as a joke. She ignored my stifled guffaw and went right on talking.

      “Given what we know about these other systems, we’d expect to find receptors, here in the epithelium lining the nose, that respond to chemicals suspended in the air or, in the case of aquatic animals, in the water that surrounds them. We’d also expect the receptors to be stimulus specific: each receptor should respond only to specific odours. The receptors should then feed their information to an olfactory centre in the brain.” She attached up the nose to a circle in the brain labelled OC.

      “Simple, right? The trouble is, nobody can find a receptor. We’ve been looking for over fifty years, and we still can’t figure out which cells in the lining of the nose are the receptors. And then there’s the problem of the stimuli. Light and sound are easy to identify and they’re simple to manipulate and measure, so we can run tests to trace the neural pathways and understand how the visual and auditory systems work. But odours? Odours are just molecules, and there are millions, billions of molecules, all different, that can become suspended in air or water. And one odour might be made up of a thousand different molecules. So what’s stimulating the receptors? Are there different receptors responding to specific molecules or discrete classes of molecules? Perhaps, but we have no idea what those molecules might be, partly because we can’t identify a receptor, and basically, if we can’t find a receptor and we don’t know what the stimuli are, its hard to study the system. Enter Madden Riesler.”

      “But he doesn’t work on olfaction. I’ve seen his records.”

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