This book, the seventh in the series 'Research and Perspectives in Neuroscience', contains the procedings of a meeting that was held in Paris on October14, 1996. The conference consisted of invited papers and poster presentations. The invited papers, included in this volume, were on cell proliferation prior to neuronal migration, on cellular and molecular factors characteristic of neuronal migration, and on postmigrational neuronal and axonal plasticity. There was a section devoted to disorders of neuronal migration and plasticity and the genetics of some developmental disorders. Great strides have been made in this relatively young branch of modern neuroscience.

The only way we can convey our thoughts in detail to another person is through verbal language. Does this imply that our thoughts ultimately rely on words? Is there only one way in which thoughts can occur? This ambitious book takes the contrary position, arguing that many possible "languages of thought" play different roles in the life of the mind.

"Language" is more than communication. It is also a means of representing information in both working and long-term memory. It provides a set of rules for combining and manipulating those representations.

A stellar lineup of international cognitive scientists, philosophers, and artists make the book's case that the brain is multilingual. Among topics discussed in the section on verbal languages are the learning of second languages, recovering language after brain damage, and sign language, and in the section on nonverbal languages, mental imagery, representations of motor activity, and the perception and representation of space.

Dyslexia and Development presents the latest findings of neurobiological research, which suggest a link between seemingly minor brain abnormalities and epilepsy, learning disorders, and autism. The authors focus on the plasticity of the developing nervous system and the possible role of subtle early brain injury in the emergence of these disorders, particularly dyslexia. The distinguished contributors to this volume examine epidemiological and clinical issues that may make the developing brain more vulnerable to environmental and genetic influences, which can in turn lead to abnormal brain plasticity and behavior. Although major forms of brain malformation have been clearly associated with functional deficits, mild forms have historically been ignored or trivialized; this book supports the hypothesis that several types of such malformation reflect brain injury during critical stages of development, and also the premise that more and more disturbances of thought and behavior stem from abnormalities of brain organization. Neurologists and neurobiologists, psychologists, psycholinguists, psychiatrists, and special educators will find here a guide to more enlightened understanding and more effective treatment of dyslexia. In fact, the book emphasizes the positive aspect of the neurobiological deviation that dyslexic brains seem to show, along with the observation that people with such brains are often quite creative and extraordinary, rather than handicapped. In turn, the revised consideration of dyslexia should lead to more serious attention to other disturbances of childhood behavior as problems in developmental neurology, as well as to a deeper analysis of possible neurological bases for individual differences in normal behavior and personality.