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Article abstract Before the discoveries of John Call Dalton, Jr., MD (1824–1889), innervation of laryngeal muscles, long-term effects of cerebellar lesions, and consequences of raised intracranial pressure were poorly understood. Dalton discovered that the posterior cricoarytenoid muscles adducted the vocal cords during inspiration. He confirmed Flourens’ observations that acute ablation of the cerebellum of pigeons caused loss of coordination. Dalton observed that properly cared for pigeons gradually recovered “coordinating power.” Dalton observed that prolonged raised intracranial pressure caused tachycardia and then fatal bradycardia in dogs. Before Dalton published his photographic atlas of the human brain, neuroanatomy atlases were sketched by Europeans and imported into the United States. Dalton’s atlas of the human brain contained precise photographs of vertical and horizontal sections that equal modern works. Before Dalton introduced live demonstrations of animals, physiology was taught by recitation of texts only. Dalton was the first American-born professor to teach physiology employing demonstrations of live animals operated on under ether anesthesia. He wrote an essay advocating experimentation on animals as the proper method of acquiring knowledge of function and that humane animal experimentation would ultimately improve the health of man and animals. His eloquent advocacy for humane experimental physiology quelled attacks by contemporaneous antivivisectionists. Dalton was America’s first experimental neurophysiologist.

Objective: To present the history of discovery of evoked potentials by reviewing the original publications of Caton, Beck, Dawson and Jewett. Background Caton9s publications revealed that unstimulated cerebral cortex had a positive charge and stimulation of an animal9s limb could produce waves of negative cortical currents in contralateral motor cortex. Design/Methods: Review of publications of Caton, Beck, Dawson and Jewett. Results: Richard Caton (1842-1926) discovered somatosensory evoked responses in 1875 Caton demonstrated fluctuations of a galvanometer connected to electrodes on exposed surfaces of rabbits9 cerebral cortex in response to stimulation of hind paws. Caton noted negative current fluctuations from occipital cortex after he shined light into retinas of rabbits. Adolph Beck in 1890 claimed primacy of discovery for similar observations. In 1947 Charles Dawson (1912-1983) superimposed amplified multiple cortical somatosensory evoked responses (SER) on a screen of an oscilloscope improving signal-to-noise ratio (SNR) of the SER. In 1954 Dawson developed the signal averager (SA) to further improve SNRs. Dawson9s SA consisted of a rotating switch driven by a motor that fed each individual scalp response to a single median nerve stimulus into 1 of 62 condensers. The SA serially discharged each condenser into an amplifier connected to a storage oscilloscope. Dawson noted that the superimposed SER had a onset latency of 28 ms. Dawson proved that SA could eliminate EEG waves not related to the stimulus. Dawson9s median SERs resembled modern cortical SERs. Conclusions: Caton should be credited as discoverer of evoked responses. Dawson should be considered founder of human evoked potentials research, because his averaging technique extracted the evoked potential. Disclosure: Dr. Fine has received personal compensation for activities with Slocum-Dickson Clinic. Dr. Fine holds stock and/or stock options in Bristol Myers-Squibb, Eli Lilly, Pfizer, and Johnson & Johnson. Dr. Riggins has nothing to disclose. Dr. Farooq has nothing to disclose.

by Paolo Mazzarello , 512 pp., Oxford University Press, 2010, $69.95 This biography extensively documents not only of the life of Camillo Golgi, co-winner of the 1906 Noble Prize in Medicine or Physiology, but also superbly summarizes his discovery of the “black reaction” staining dendrites and axons, the reticular system (Golgi apparatus), and life cycles of parasites. Mazzarello exposes Golgi's errors in constructing and then doggedly defending the reticular theory of neuroanatomy, and his struggles to strengthen the University of Pavia Medical School, his alma mater. In chapter 2, Mazzarello recounts Golgi's ancestry, as well as elementary and medical schooling. Chapter 3 expertly epitomizes the evolution …

edited by Javier DeFelipe , 432 pp., Oxford Press, 2010, $75 This exquisitely illustrated book was edited by Javier DeFelipe, an internationally known interpreter of and translator of Santiago Ramon y Cajal's writings and member of the Insituto Cajal in Madrid, Spain. The curious title derives from Cajal's' Recuerdos de Mi Vida , in which he wrote that “. . . my attention was drawn to the flower garden of the gray matter, which contained cells with delicate and elegant forms, the mysterious butterflies of the soul , the beating of whose wings may some day (who knows) clarify the secret of mental life.” The book is divided into Introduction and the Gallery of Drawings. The Introduction contains introductory remarks that describe anatomic features of neurons and glia with their interrelations. A Sketch History of the …