Bradford Books

Written for research neurologists, this handsomely printed book introduces the subject of transcranial magnetic stimulation (TMS), which joins electroencephalography (EEG), event related potentials (ERPs), magnetoencephalography (MEG), functional magnetic resonance imaging (fMRI), and positron emission tomography (PET) as a new tool for studying the dynamics of the human brain. In simplest terms, TMS floods a restricted region of the neocortex with a large magnetic field (about 2 tesla or 20,000 gauss) for a fraction of a millisecond. In order to influence brain dynamics, it is now understood, a magnetic field must be rather large (the earth's magnetic field is about 0.5 gauss), and it must be rapidly established. The broad effect of such a sudden intrusion of magnetic field energy is to introduce computational noise into the neocortical dynamics, interfering with motor activity and causing the perception of spots of light (phosphenes), in addition to more subtly influencing the brain's behavior in a variety of ways.

The basic idea of TMS is simple---a steady voltage source (power supply) charges a storage capacitor to some 2 kilojoules of energy, which is suddenly discharged as magnetic field energy through a magnetic stimulating coil by closing a solid-state switch. In an interesting early chapter, the authors of Transcranial Magnetic Stimulation trace the checkered history of related ideas from the discovery of magnetic induction by Michael Faraday in 1831 to the practical realization of TMS by Anthony Barker and his colleagues at Sheffield, England in the mid-1980s. Why ``checkered''? Our brains are relatively insensitive to magnetic fields of ordinary strength (try waving a horseshoe magnet near your temple) so much of the nineteenth-century speculation on mental effects of magnetic fields was pseudoscientific or worse. The brain is insensitive to magnetic fields because it is not an electromagnetic medium. In other words, cortical dynamics are dominated by interacting electric fields and ionic currents, in which magnetic fields play only minor roles.

Normal cortical currents generate minute magnetic fields which are observed in MEG measurements, and the very large external magnetic fields that are suddenly turned on under TMS generate small transmembrane voltages that may influence the course of these currents, but this picture is very different from a true electromagnetic medium---such as a propagating radio wave or the output light beam from a laser---in which the total energy remains essentially conserved as it oscillates rapidly back and forth between electric and magnetic energy. In the brain, to the contrary, electric field energy is continually being generated by hydrolysis of adenosine triphosphate, stored in transmembrane potentials, and dissipated through myriad nonlinear electric field interactions with transmembrane ionic currents. Whatever small magnetic fields that are present do not influence normal functioning of the brain.

In neuroscience research, TMS has the advantage of acting as a noninvasive ``virtual lesion'' which can be rapidly induced over a region that penetrates an inch or so into the neocortex and is transversely localized to roughly a square inch. Because cortical fibers are somewhat randomly oriented, such a localized and rapidly rising TMS field generates a random spectrum of transmembrane voltages that are either excitatory or inhibitory depending on the local orientation of a particular fiber, thereby introducing the functional equivalent of computational noise. About 20 ms after the end of a TMS pulse, the major effects disappear, and an experiment can be repeated; thus it is feasible to measure changes in timing delays for various motor responses as the stimulating coil is moved over the scalp, a research activity of considerable current interest. In addition to such timing experiments, which the authors of this book describe in some detail, there is also the possibility of using TMS in a ``repetitive'' mode called rTMS. In this mode, a periodic series of magnetic pulses are generated, and the experimenter has the opportunity of introducing steady noise into a restricted volume of the cortical dynamics for a well defined interval of time. This leads to the possibility of observing subsequent effects on a variety of subtle cognitive activities, many of which are reviewed and described in this book.

TMS safety is evidently a key concern; the authors mention that no one with a history of epilepsy should be used as a subject. Clearly this is a matter that neuropsychological researchers should consider carefully as they put their subjects through an increasing variety of subjective experiences, including visual suppression and extinction, search interference, geometrical perception, perception of temporal sequence, variations in attention, perceptual learning, and memory inhibition. Considering all of these possible applications, it seems safe to predict that both TMS and rTMS will make important contributions to research in neuropsychology over the next few years. As an introduction, Transcranial Magnetic Stimulation is highly recommended for all who would take up this exciting activity.

Alwyn Scott
http://personal.riverusers.com/~rover/

I found this book enormously helpful. It contains most of the classic recent papers on vagueness in the analytic tradition from Dummett onward, plus a little pre-history, a few small curiosities (the papers by Tye and Machina, for example, seem to have been included mostly for their novelty value, but I found them both interesting and worth the effort) and a very comprehensive introdution that covers most of the main theories of vagueness that contemporary philosophers tend to find most plausible. The issue of vagueness is slowly coming to attract the same intensity and vigor of debate that the issue of analyticity did in the 1950s and 1960s, and this makes the value of Keefe and Smith's work almost impossible to measure. If only more anthologies of recent work in philosophy were assembled this carefully and intelligently!

In this monograph are contained a plethora of poetic nuggets expressing wisdom and power. Though Mr. Mutwa fairly skims over a lot of territory, at critical junctures he dips into the fountainhead of traditional and experiential knowledge which he has become heir to during his long life.

There are items of spiritual knowledge that I came into contact with while studying to take initiations from Peruvian shamans of the High Altiplano eight or so years ago, which I found echoed in rather precise detail here. I have never seen them anywhere else. And this book was only published a couple of years ago.

Please note that there are less than 100 pages of actual written text (the rest of the book is filled with lots of color photos of his giant sculptural work and various other photos of his environs, himself, his friends and relatives.

On the CD (also 5 stars):

"Call of the Sacred Drums" 1:48 [inspired, traditional Zulu drumming/singing, medium tempo]

"The Incredible Credo Mutwa" 4:11 [speech honoring Mutwa, by Otsile Ntsoan, in English and Zulu: very beautiful & inspiring]

"Nduli" 2:11 [traditional Zulu drumming/homophonic choral singing, medium tempo]

"Isindawo" 3:43 [traditional Zulu drumming/homophonic choral singing, medium tempo]

"My Initiation Story" 38:29 [Mutwa tells part of his story, mentioning the severe purification practices one must undergo, and ritual dancing, 'kundalini' experiences, astral travel, unity consciousness and beyond, development of compassion and experiences of ecstasy, distant sensing. Note that this story is transcribed as part of the text of the book.]

"Umtchongola" 3:04 [traditional up-tempo Zulu dance drumming]

"Makhosi Asevukile" 2:59 [traditional Zulu homophonic choral singing with drum accompaniment, slow tempo]

"Sele" 3:27 [traditional Zulu dance drumming/singing; with a long, very slow recitative sung as an introduction, punctuated with drum rolls; and with a similar postlude]

"Blessing by Vusamazulu" 6:31

"African Friends" 3:05 (lighthearted music & lyrics by Keeney, in American folk-pop style, sung by the Wade Sisters)

This is a survival guide for handcrafters that is only maybe a step above primitive living skills! I found this book very useful and in fact is probably one of the books that inspired me to learn more about primitive living, wilderness skills and survival. This book may be from 1973 but the information contained in it is still a great introduction to the basic skills required to improvise in a survival situation or give yourself a challenging project to do next time your camping or sitting at home wanting to fiddle with something. Here's whats in it: Carrying Gear, Shelter, Fire Making & Lighting in the Dark, Keeping Warm at Night, Camp Furniture, Clothes & Personal Items, Cooking Gear, Catching Food, Water Supply, Tools & Implements, Avoiding GettingLost, Transportation. No high tech stuff here just your basic survival skills needed for camping, hiking and wilderness living! I recommend this book to those who are looking for an introduction to these skills.

I have all seven of the Wildlife Photographer of the Year portfolios. They feature all of the top wildlife/nature photographers; Mangelson,Lanting,Wolfe. If you like beautiful pictures of nature and/or animals, you'll love this book!

I chose this book to round out a study of the early colonies for my 4th and 6th grade boys. I would say it is geared more for 7th grade and up. But since I read it to them I could explain some of the things that they did not understand right off. I was extremely pleased with how Mr. Schmidt rendered Brandford's, "Of Plymouth Plantation" into a useable and understandable text for today's reader.
After reading this book I feel cheated in my education as to the true lives of the original Pilgrims. All the hardships that they faced year after year.
As much as I learned in school, it would be like explaining "The Lord of the Rings" as, A hobbit named Frodo recieved a special ring and was told to destroy it. He found some friends to help him, together they faced much danger, but in the end it was destroyed.
The book is a very thorough explanation, with many quotes, of the hardships the Separatists faced before they came, as they came, and after they arrived. I was amazed at the fortitude of the Pilgrims in general. I don't believe many people today would have held on to their faith or striven against such unjustices with such faithfulness and patience.
I will definetly be using this book again in the future. It was an excellent primary source.

This is truly a book that every American should read. It tells in a marvelous readable style the true story of one of our greatest American heroes. The Pilgrim story is one that has been relegated in its importance in our revisionist history books, especially in our public schools. Knowing our true history and giving honor to our heroes is vital to our strength as a nation. This book accomplishes these goals.

I am so happy with this recent purchase, it is a perfect addition to any coffee table. The paintings are beautiful and the conversation between Mr. McCullough and Mr. Badwin is both intriguing and witty. I recommend it for anyone, even those not particularly interested in art or southern culture. Those who are interested in those should definitely have a look into it though!

This readable guide provides step-by-step background and instructions for the small claims process. It explains what cases are and are not appropriate for small claims court, in which county to file, how to file, how to prepare for the trial, what happens at the trial, and how to collect a judgement. The book provides guidance to both plaintifs and defendants.

This book is refreshingly different to most war stories. It tells of the lifes of one family as they live through the years of WWII. It is a poignant and sometimes humerous story in spite of the terrible hardships experienced by members of the family. Although seen through the eyes of a German family,it is the story of ordinary people caught up in a war they had no choice but to endure. Interesting and entertaining reading.