Right Hand, Left Hand


Book Description

McManus considers evidence from anthropology, particle physics, the history of medicine, and the notebooks of Leonardo to answer questions like: Why are most people right-handed? Why does European writing go from left to right, while Arabic and Hebrew go from right to left? And how do we know that Jack the Ripper was left-handed?




Handedness and Brain Asymmetry


Book Description

Brain asymmetry for speech is moderately related to handedness but what are the rules? Are symmetries for hand and brain associated with characteristics such as intelligence, motor skill, spatial reasoning or skill at sports? In this follow up to the influential Left, Right Hand and Brain (1985) Marian Annett draws on a working lifetime of research to help provide answers to crucial questions. Central to her argument is the Right Shift Theory - her original and innovative contribution to the field that seeks to explain the relationships between left-and right-handedness and left-and right-brain specialisation. The theory proposes that handedness in humans and our non-human primate relations depends on chance but that chance is weighted towards right-handedness in most people by an agent of right-hemisphere disadvantage. It argues for the existence of a single gene for right shift (RS+) that evolved in humans to aid the growth of speech in the left hemisphere of the brain. The Right Shift Theory has possible implications for a wide range of questions about human abilities and disabilities, including verbal and non verbal intelligence, educational progress and dyslexia, spatial reasoning, sporting skills and mental illness. It continues to be at the cutting edge of research, solving problems and generating new avenues of investigation - most recently the surprising idea that a mutant RS+ gene might be involved in the causes of schizophrenia and autism. Handedness and Brain Asymmetry will make fascinating reading for students and researchers in psychology and neurology, educationalists, and anyone with a keen interest in why people have different talents and weaknesses.




On the Other Hand


Book Description

Does being left-handed make a person different in any way that matters? Since the late Stone Age, approximately 10 percent of humans have been left-handed, yet for most of human history left-handedness has been stigmatized. In On the Other Hand, Howard I. Kushner traces the impact of left-handedness on human cognition, behavior, culture, and health. A left-hander himself, Kushner has long been interested in the meanings associated with left-handedness, and ultimately with whether hand preference can even be defined in a significant way. As he explores the medical and cultural history of left-handedness, Kushner describes the associated taboos, rituals, and stigma from around the globe. The words “left” and “left hand” have negative connotations in all languages, and left-handers have even historically been viewed as disabled. In this comprehensive history of left-handedness, Kushner asks why left-handedness exists. He examines the relationship—if any—between handedness, linguistics, and learning disabilities, reveals how toleration of left-handedness serves as a barometer of wider cultural toleration and permissiveness, and wonders why the reported number of left-handers is significantly lower in Asia and Africa than in the West. Written in a lively style that mixes personal biography with scholarly research, On the Other Hand tells a comprehensive story about the science, traditions, and prejudices surrounding left-handedness.




The Puzzle of Left-handedness


Book Description

Ronald Reagan and Barack Obama have both signed bills into law with their left hands. And being left-handed certainly did not hold back the artistic achievements of Michelangelo or Raphael. And the dexterous guitar playing of Jimmi Hendrix may only have been aided by his southpaw tendencies. Left-handedness, in fact, would appear to be no big deal. Yet throughout history, it has been associated with clumsiness and generally dubious personality traits like untrustworthiness and insincerity. Even the Latin word for left, sinister, has ominous connotations. In The Puzzle of Left-handedness, Rik Smits uncovers why history has been so unkind to our lefthanded forebears. He carefully puts together the pieces of the puzzle, presenting an array of historical anecdotes, strange superstitions, and weird wives’ tales. Smits explains how left-handedness continues to be associated with maladies of all kinds, including mental retardation, alcoholism, asthma, hay fever, cancer, diabetes, insomnia, depression, and criminality. Even in the enlightened twenty-first century, left-handedness still meets with opposition—including from one prominent psychologist who equates it with infantile negativism, similar to a toddler’s refusal to eat what’s on his plate, and another who claims that left-handed people have average lifespans that are nine years shorter than those who favor the right hand. As Smits reminds us, such speculation is backed by little factual evidence, and the arguments presented by proponents of right-handedness tend to be humorously absurd. The Puzzle of Left-handedness is an enlightening, engaging, and entertaining odyssey through the puzzles and paradoxes, theories and myths, of left-handed lore. Chock full of facts and fiction, it’s a book to be read with both hands.




Laterality Functional Asymmetry in the Intact Brain


Book Description

Laterality: Functional Asymmetry in the Intact Brain focuses on brain function and laterality as well as the various methods in assessing behavioral asymmetries, including handedness. It reviews the literature on perceptual-cognitive laterality effects in different sensory modalities, the lateralization of emotion and motor behavior, and the electrophysiological evidence. It also highlights some of the problems with the existing research and offers suggestions about the direction of future research. Organized into 17 chapters, this volume begins with an overview of cerebral asymmetry and the origins and mechanisms of lateralization. Then, it discusses the individual differences in laterality, methods and measurement used in laterality studies, and experiments on dichotic listening and auditory lateralization. The next chapters focus on the link between verbal laterality and handedness, tactual and perceptual laterality, asymmetry of motor performance, lateralization of emotional processes, and physiological measures of asymmetry. The book also introduces the handedness and its relation to cerebral function, genetics of laterality, development of cerebral lateralization, individual differences in cerebral organization, sex differences in laterality, reading- and language-related deficits, and control of the active hemisphere before concluding with a chapter discussing the experimental or strategy effects, the concept of complementary specialization, and the dichotomy between the two hemispheres of the brain. This book is a valuable resource for neuropsychologists, experimental psychologists, neurologists, and educators interested in understanding human brain function.




Biological Asymmetry and Handedness


Book Description

Examines the progress of leading scientists working on various aspects of handedness in order to consider the occurrence of handedness in the biological world. Provides in-depth coverage of the origin and development of morphological asymmetry occurring in most types of living organisms.




Neuropsychology of Left-Handedness


Book Description

Neuropsychology of Left-Handedness focuses on the neurological imperative and unique brain organization of left-handers. This book is organized into two parts. Part I analyzes ideas about the origins of left-handedness, such as possible genetic mechanisms, manner in which asymmetries may occur during the first cell cleavages following fertilization, handedness of twins, and possibility that some left-handedness may be due to environmental or even pathological influences. The second part is devoted to a variety of investigations of asymmetric hemisphere specialization in right- and left-handers. The different groups of left-handers, which includes male and female, strong left-preferrers and ambidexters, familial and non-familial lefthanders, and those who prefer an “inverted position for writing as opposed to a “non-inverted position, are also identified. This publication is a good reference for medical practitioners and specialists interested in the neuropsychology of left-handedness.




Hemispheric Asymmetry


Book Description

Is "right-brain" thought essentially creative, and "left-brain" strictly logical? Joseph B. Hellige argues that this view is far too simplistic. Surveying extensive data in the field of cognitive science, he disentangles scientific facts from popular assumptions about the brain's two hemispheres. In Hemispheric Asymmetry, Hellige explains that the "right brain" and "left brain" are actually components of a much larger cognitive system encompassing cortical and subcortical structures, all of which interact to produce unity of thought and action. He further explores questions of whether hemispheric asymmetry is unique to humans, and how it might have evolved. This book is a valuable overview of hemispheric asymmetry and its evolutionary precedents.




The Two Halves of the Brain


Book Description

State-of-the-art research on brain asymmetry, explained from molecular to clinical levels. Hemispheric asymmetry is one of the basic aspects of perception and cognitive processing. The different functions of the left and right hemispheres of the brain have been studied with renewed interest in recent years, as scholars explore applications to new areas, new measuring techniques, and new theoretical approaches. This volume provides a comprehensive view of the latest research in brain asymmetry, offering not only recent empirical and clinical findings but also a coherent theoretical approach to the subject. In chapters that report on the field at levels from the molecular to the clinical, leading researchers address such topics as the evolution and genetics of brain asymmetry; animal models; findings from structural and functional neuroimaging techniques and research; sex differences and hormonal effects; sleep asymmetry; cognitive asymmetry in visual and auditory perception; and auditory laterality and speech perception, memory, and asymmetry in the context of developmental, neurological, and psychiatric disorders. Contributors Katrin Amunts, Ulrike Bayer, Alfredo Brancucci, Vince D. Calhoun, Maria Casagrande, Marco Catani, Michael C. Corballis, Patricia E. Cowell, Timothy J. Crow, Tom Eichele, Stephanie Forkel, Patrick J. Gannon, Isabelle George, Onur Güntürkün, Heikki Hämäläinen, Markus Hausmann, Joseph B. Hellige, Kenneth Hugdahl, Masud Husain, Grégoria Kalpouzos, Bruno Laeng, Martina Manns, Chikashi Michimata, Deborah W. Moncrieff, Lars Nyberg, Godfrey Pearlson, Stefan Pollmann, Victoria Singh-Curry, Iris E.C. Sommer, Tao Sun, Nathan Swanson, Fiia Takio, Michel Thiebaut de Schotten, René Westerhausen