The Basic Mechanisms Responsible for the Bimanual Behavior

One of the most remarkable abilities of human behavior is using our upper extremities is using our upper limbs to produce manipulative activities such as using tools, preparing, and consuming food, and performing sport activities. Our two hands tend to have specific roles to complete a manual task. The dominant hand takes a leading role and the “non-dominant” hand a more supporting role. In other cases, such as when lifting the pot by the handle, both hands play a more active role. In addition, self-care tasks (such as eating, drinking, personal hygiene) often require bimanual hand control. The study of different capabilities in bimanual performance has recently gained increasing attention for at least two main reasons. First, they represent a special case of multitasking, informing us about how the central nervous system (CNS) coordinates the organization of multiple command streams. Second, bimanual tasks are mostly suitable to reveal motor dysfunctions in general and processes of lateralization and asymmetry, following neurodegenerative diseases and other brain pathologies, such as Parkinson Disease. To our knowledge, the relative contributions of these behavioral-related brain regions and cognitive mechanisms are still poorly understood and hotly debated. To our knowledge, the relative contributions of the brain regions and cognitive mechanisms implicated in this behavior are poorly understood and strongly debated.

Object manipulation requires the coordination of two hands in space, time, and force. Bimanual behavior requires coordination of many specific features, and each presents fascinating questions about how the movement is organized in the CNS. Additionally, object manipulation is a typical circumstance in which two hands work together to complete a single task, such as opening a jar. The neural pathways that underlie these activities and how they are represented in the brain are usually overlooked. The task itself may specify the binding properties of such bimanual movements. Our aim will be to gather contributions from prominent researchers in the field that emphasize how bimanual behavior occurs as a result of the internal factors (each hand's kinematics and dynamics coordinated in time and space) interacting with external factors such as object mechanical characteristics and task demands.

We hope to host a distinguished group of authors to shed light on existing hemispheric asymmetries in bimanual behavior. We are confident that the articles chosen will lead to a deeper understanding of interhemispheric interactions and the ability of the two hemispheres to work in parallel.

At the same time, we aim to collect evidence about the brain structures that have a particular function in bimanual movements that is distinct from what is necessary for unimanual ones.

Our intention was to bring together first- and last-generation neuroscientists, as well as clinical researchers, to create a comprehensive overview of what we know about the neurocognitive mechanisms and neural substrates that confer a special status to bimanual behavior.

To understand and appreciate how the human brain controls both hands, it is necessary to collect evidence of both healthy and dysfunctional motor behavior during ordinary manipulation activities.The problems of bimanual control are central to understanding interhemispheric reorganization that occurs in the setting of brain injury and may ultimately impact on rehabilitative strategies in patients.

We therefore invite contributions, including Research Articles and Reviews which provide evidence about the capacity to perform bimanual actions from multiple descriptive levels, including behavior, neuropsychological, neuroimaging, and electrophysiological. We also appreciate contributions providing relevant computational theories and explanations.