Circuits for Movement
How we move
The 2022 Brain Prize was awarded to an international group of three neuroscientists, Silvia Arber (Switzerland) Martyn Goulding (USA/NZ), Ole Kiehn (Denmark), for their pioneering research into the neuronal circuits that control movement that has revolutionised our understanding of the cell types and circuits that control how we move.
Most of our interactions with the world depend on our ability to move. Understanding how the nervous system generates movement is a fundamental goal of neuroscience and is at the heart of devising new strategies for the restoration of movement following injury or disease. Understanding the circuits that produce movement has long been at the heart of understanding how nervous systems produce behaviour.
The circuits that control movement are widely distributed throughout the brain and spinal cord. They are composed of many different neuronal cell types, each with characteristic functional properties and patterns of connectivity, which can be tricky to isolate and study.
Classical approaches to studying the brain, such as electrical recordings of individual neurons, pharmacological manipulations or lesioning of different brain areas have provided important insights into the neural control of movement but have been limited as they cannot be used to reliably identify, interrogate, and manipulate individual neuronal cell types.
However, cell types within the spinal cord can be distinguished from one another by the pattern of developmentally important genes that they express. Using these distinctions, Silvia Arber, Martyn Goulding and Ole Kiehn characterized and analysed the roles of identified cell types by combining molecular genetic with classical approaches in mice.
Working in parallel and sometimes together, Arber, Kiehn and Goulding have used these techniques to describe in unprecedented detail the cells and circuits that control diverse aspects of the movement repertoire. They identified neuronal components of the spinal circuitry and defined how each of them contribute to distinct aspects of locomotion in cats and mice. They found components of the mammalian spinal network that ensure that when we move from A to B we can do so at different speeds, and with different gaits that are stable, balanced, and rhythmic.
However, locomotion represents just a small part of an animal’s movement repertoire. For example, mice use dextrous movements of their forelimbs for grasping and handling food. Work from Silvia Arber’s lab has shown that there are areas of the brainstem that are dedicated to controlling forelimb movement and that within the brainstem there are neurons that are dedicated to specific phases of forelimb movements such as reaching or food handling.
The work of Kiehn and Arber demonstrated the exquisite organisation of brainstem command pathways to the spinal cord at the cellular level. Acting like a neuronal switchboard that directs plans for movement from mid- and forebrain structures to the spinal cord, it controls diverse aspects of movement from locomotion to the delicate and dextrous movements of the limbs.
Information also goes both ways. Modulation of the motor system by the senses is crucial for adapting our movements according to ongoing changes in the environment. Goulding identified neurons in the spinal cord that serve as an interface between sensory and motor systems. These neurons receive input from sensory neurons in the skin that convey information about light-touch stimuli and ablating them markedly reduces the behavioural responses of mice to light touch and dramatically increases the frequency of foot slips when mice are walking along a beam.
By revealing how identified populations of cell types in the brainstem and spinal cord contribute to specific aspects of movement, Arber, Kiehn and Goulding have highlighted the need and paved the way for cell-type-specific diagnostics and interventions in movement disorders.
For more information :
https://lundbeckfonden.com/files/media/document/The%20Brain%20Prize%202022%20Information%20Pack.pdf
Last edited: 28 February 2025 16:15