How We Learned That the Body and Brain Are Electric MachinesBook - 2016
Like all cellular organisms, humans run on electricity. Slight imbalances of electric charge across cell membranes result in sensation, movement, awareness, and thinking—nearly everything we associate with being alive. Robert Campenot offers a comprehensive overview of animal electricity, examining its physiological mechanisms as well as the experimental discoveries that form the basis for our modern understanding of nervous systems across the animal kingdom.
Cells work much like batteries. Concentration gradients of sodium and potassium cause these ions to flow in and out of cells by way of protein channels, creating tiny voltages across the cell membrane. The cellular mechanisms that switch these ion currents on and off drive all the functions associated with animal nervous systems, from nerve impulses and heartbeats to the 600-volt shocks produced by electric eels.
Campenot’s examination of the nervous system is presented in the context of ideas as they evolved in the past, as well as today’s research and its future implications. The discussion ranges from the pre-Renaissance notion of animal spirits and Galvani’s eighteenth-century discovery of animal electricity, to modern insights into how electrical activity produces learning and how electrical signals in the cortex can be used to connect the brains of paralyzed individuals to limbs or prosthetic devices. Campenot provides the necessary scientific background to make the book highly accessible for general readers while conveying much about the process of scientific discovery.
Like all cellular organisms humans run on electricity. Cells work like batteries: slight imbalances of electric charge across cell membranes, caused by ions moving in and out of cells, result in sensation, movement, awareness, and thinking—the things we associate with being alive. Robert Campenot offers an accessible overview of animal electricity.
Campenot presents this scientific explanation and science history for the general public of bioelectricity, from conduction in the brain and nervous system to the delicate signaling across all cell membranes to dramatic capabilites like those of electric eels. The first chapter presents the history of early scientists who discovered the rudiments of electricity and reviews the high-school-level calculations associated with these phenomena. The next several chapters dig into the methods and results of microscopic biology, and describe the electrical states of cells, including membrane potentials, ion channels, and action potentials. The book then expands to discuss intracellular connections and communication between cells, including neural synapses and neuromuscular junctions, developmental plasticity, and learning, as well as how the longer-range traces of these electrical currents can be amplified to deliver a shock, used by predators to locate prey, and detected by medical technology to help diagnose a patient. The final chapter showcases examples of developing bionic technologies including prosthetic nerves, hearing aids, and retinal implants. Annotation ©2016 Ringgold, Inc., Portland, OR (protoview.com)