Manual Skills, Handedness, and the Organization of Language in the Brain


Book Description

Whereas the cerebral specialization for skilled manual actions (praxis) seems closely linked to dominance for language, with both functions left lateralized in the vast majority of humans, the neural correlates of hand preference are still less well understood. Indeed, as a combination of inherited and non-inherited genomic factors (i.e., direct parental and concealed environmental contributions), handedness – in contrast to language – is less likely to have strong genetic indices and clearly lateralized functional organization. What about eye dominance, unimanual and bimanual object manipulation, and gestures, or attentional systems and the related egocentric or allocentric coding of space? Are these different categories functionally and structurally interconnected? Is their development and contribution to task performance linked, even if they are differently lateralized? How are they connected to language learning or its development? In trying to understand these relationships and their neural underpinnings we obtain a new insight into fundamental human behaviors, which depend either on shared or distinct cerebral resources that must, nevertheless, be harmonized by higher-order cerebral processing. In this Research Topic we assembled a dozen of original research contributions, as well as articles with more theoretically-driven perspectives, that directly speak to these issues. Hopefully this work will serve as a foundation for further discussions and will stimulate new research in this fascinating domain.




Causality and Neo-Stages in Development


Book Description

This book represents a broad integration of several major themes in psychology toward its unification. Unifying psychology is an ongoing project that has no end-point, but the present work suggests several major axes toward that end, including causality and activation-inhibition coordination. On the development side of the model building, the author has constructed an integrated lifespan stage model of development across the Piagetian cognitive and the Eriksonian socioaffective domains. The model is based on the concept of neo-stages, which mitigates standard criticisms of developmental stage models. The new work in the second half of the book extends the primary work in the first half both in terms of causality and development. Also, the area of couple work is examined from the stage perspective. Finally, new concepts related to the main themes are represented, including on the science formula, executive function, stress dysregulation disorder, inner peace, and ethics, all toward showing the rich potential of the present modeling.




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.




Handbook of Neuropsychological Assessment


Book Description

The growth of clinical neuropsychology has been unprecedented. This growth has been oriented more toward the provision of than toward the foundation for services. Thus, while a greater number of psychologists are performing a greater number of neuropsychological procedures, there seems to us an uneven parallel growth between these services and the empirical foundations for them. It should come to no one's surprise that increasingly aggressive attacks on the field have been leveled. Despite these attacks, clinical neuropsychology con tinues to enjoy exceptional growth within psychology and acceptance by other health practitioners, insurance companies, legislators, judges, juries, and above all, consumers of our services. Growth without self-reflection is a dangerous enterprise, as is growth without directions. We find it disconcerting that existing and limited "self analysis" has assumed that neuropsychological dysfunction is immune to the same variables that affect psychological dysfunction. Some attention has been paid to the most obvious ones, such as age, but all others have been ignored and/ or misunderstood. This neglect has spawned a body of knowledge replete with questionable data and unfounded conclusions. Hence, it is surprising that clinical neuropsychologists consider themselves to be more scientifically sound than their regular clinical counterparts.




Cerebral Lateralization and Cognition: Evolutionary and Developmental Investigations of Behavioral Biases


Book Description

Cerebral Lateralization and Cognition: Evolutionary and Developmental Investigations of Motor Biases, Volume 238, the latest release in the Progress in Brain Research series, discusses interdisciplinary research on the influence of cerebral lateralization on cognition within an evolutionary framework. Chapters of note in this release include Evolutionary Perspectives: Visual/Motor Biases and Cognition, Manual laterality and cognition through evolution: An archeological perspective, Laterality in insects, Motor asymmetries in fish, amphibians and reptiles, Visual biases and social cognition in animals, Mother and offspring lateralized social interaction across animal species, Manual bias, personality and cognition in common marmosets and other primates, and more. - Presents investigations of cognitive development in an evolutionary framework - Provides a better understanding of the causal relationship between motor function and brain organization - Brings clinicians and neuroscientists together to consider the relevance of motor biases as behavioral biomarkers of cognitive disorders - Includes future possibilities for early detection and motor intervention therapies




Handedness and Developmental Disorder


Book Description

This book offers a comprehensive and readable account of theoretical aspects of the origins and normal development of handedness and its relationship to cerebral lateralization. It reviews the evidence for links between non-right-handedness and various developmental disorders: mental impairment, autism, epilepsy, and disorders of spoken and written language. The emphasis is on understanding the range of underlying mechanisms that might lead to associations between handedness and disorder and on identifying assessment procedures that can distinguish between different explanations.




Language Lateralization and Psychosis


Book Description

Illustrates important fundamental aspects of cerebral lateralization, explaining how decreased language lateralization can facilitate psychotic symptoms in the human brain.




Cerebral Laterality


Book Description

Research on clinical populations and studies of normal individuals support the conclusion that there are functional differences between the cerebral hemispheres. This book captures some of the major developments in the field of cerebral laterality research of the last five years. These include lateralization in non-human primates, computational models of hemispheric processing, hemispheric transfer and interaction, perceptual asymmetries, techniques to measure dynamic changes in hemispheric processing of information, and new conceptualizations of the relation between handedness and cerebral laterality. The topics discussed exhibit an interconnectedness such that the approaches and techniques used in one area of cerebral laterality research have implications for research in other disciplines. They also reflect changes in the conceptualization of general theoretical issues regarding cerebral laterality research.




Manual Specialization and the Developing Brain


Book Description

Manual Specialization and the Developing Brain deals with how the hands acquire different skills and what this may tell about the child's developing brain. This book is organized into three parts. Part I provides a general overview of lateralization development, while Part II compiles contributions that are more theoretical in nature. The last part summarizes the empirical research with neonates. This text specifically discusses the studies of early lateralized manual behaviors, character of human handedness, and factors that contribute toward variability in lateralization. The hemisphere differences in response to specific stimulus cues, phylogenetic perspective, and infant motor skills project are also elaborated. This text likewise covers the developmental view of hemispheric specialization and changes and constancies in development. This publication is useful to pediatricians, medical practitioners, and researchers concerned with early lateralized behavior.




Left-Handedness: Behavioral Implications and Anomalies


Book Description

Left-handedness has been shown to be a possible marker for various psychological and physical abnormalities. This book presents evidence by a number of researchers who evaluate whether there are indeed differences between left- and right-handers which extend into the broader psychological and physiological realms.Several chapters show that left-handedness is found in unexpectedly high proportions in populations that suffer from various immune deficiency diseases, in alcoholics, dyslexics, mental retardates, psychopaths and other clinical groups. The book indicates why left-handedness should be a marker for such conditions. The genetic and environmental pressures on handedness are explored. A model for pathological left-handedness is presented, along with some interesting data which suggests that left-handedness may be associated with reduced life-span. Finally, several chapters discuss the implications of handedness patterns in non-clinical populations.