UCL Institute of Neurology


Prof. R. Lemon

Cortical Control of Skilled Hand Function

The Lemon laboratory is devoted to understanding the cerebral control of hand and finger movements in humans and in non-human primate models. Our interest is prompted by the need to understand why hand and finger movements are particularly affected by damage to the cortex, and its major descending pathways, for instance as a result of stroke, spinal injury or cerebral palsy.

Non-human primates provide the best available animal model for the human sensorimotor system controlling the hand. Our work has provided important evidence that direct cortico-motoneuronal (CM) projections from primary motor cortex to spinal motoneurons are particularly important for the performance of skilled hand and finger movements.

We are also interested in visuomotor control. We have characterised the cortico-cortical pathways which allow visual information about the shape, size and other properties of graspable objects to modulate corticospinal outputs from primary motor cortex (M1).

We are also working on the brain mechanisms involved in tool use by non-human primates, and in particular how corticospinal and CM activity contributes to tool use.

We have recently made some interesting discoveries relating to the mirror neuron system and this now forms another part of our research programme.

All our current projects involve multidisciplinary approaches to the motor system, including:

  • Performance of a wide variety of skilled hand tasks carried out by human volunteers, patients and trained experimental primates
  • Multiple microelectrode recording in primates from identified output neurons and local field potentials in cortical areas involved in hand control, using the Thomas Recording system, and guided by MRI scans
  • Parallel studies using chronically implanted electrode arrays
  • Electrophysiological studies of descending motor pathways in primate models
  • Using a variety of non-invasive techniques (paired pulse TMS, rTMS, fMRI) to investigate the human visuomotor grasping circuit.

Research Group Members

Lab. Head: Professor Roger Lemon (Publications)

Dr Alexander Kraskov (Senior Research Fellow)

Dr Roland Philipp (Research Fellow)

Dr Stephan Waldert (Marie Curie Research Fellow)

Ganesh Vigneswaran (UCL Grand Challenge PhD Student)

Samantha Shepherd (Senior Research Technician)

Current Grant Support

Wellcome Trust Project Grant (Lemon and Kraskov)

Wellcome Trust Project Grant (Kraskov and Lemon)

UCL Grand Challenge PhD Studentship (Ganesh Vigneswaran)

Marie Curie postdoctoral fellowship (Stephan Waldert)

Exchange grant with RIKEN Brain Science Institute, Tokyo, Japan