This 15th volume in the Extraordinary Brain Series is focused on research in dyslexia and neuroscience in response to the Geschwind-Galabura hypothesis that defined the field of dyslexia 30 years ago. In the 1980s, Norman Geschwind and Peter Behan reported increased prevalence of left-handedness and autoimmune disorders in individuals and families with developmental dyslexia. Following this report, Geschwind, in collaboration with Albert Galaburda, wrote a paper in the Archives of Neurology discussing developmentally relevant associations between brain development, hormones, immune activity, and brain lateralization, which resulted in human diversity in talents and disabilities. There have been many technological advances in laboratory science, neuroimaging, genetics, and behavioral science in the last 30 years. Still, many of the questions and issues raised in this landmark paper have not been definitively addressed. Invited attendees of the 2016 Extraordinary Brain Symposium (hosted by The Dyslexia Foundation) revisited the hypothesis and assessed what remains to be investigated; this book is based on the attendees' Symposium presentations.