Research theme: The overall goal of our research is to unravel the neural sensorimotor mechanisms that endow humans with their extraordinary ability to manipulate physical objects with their hands. Specifically, we want to capture the relevant schemes of the automatically operating task dependent interactions between various sensory and motor mechanisms used in dexterous manipulation. These include memory mechanisms that establish motor output parameters and sensorimotor transformations. We likewise investigate neural sensorimotor mechanisms in the control of oral and oromanual skilful behaviors in humans. Our research on the control of human dexterous behavior range from analyses of peripheral sensor and effector mechanisms, to system analysis of sensorimotor control strategies and distributed control processes in the human CNS. In addition to its obvious importance for human neuroscience, our work in this field has proven to be of significance also for applied sciences, including clinical-medical and technological applications.
Experimental approach: In experimentation on operative humans, we use new specially designed instrumentation combined with proven experimental techniques. We expose basic mechanisms of coordination within and among digits in multidigit manipulative tasks with multidimensional recordings of fingertip forces, torques and movements, and we monitor motoneuronal signals with multichannel EMG. We use microneurographic techniques to define how populations of tactile and other somatosensory afferent neurons encode the mechanical control events that the CNS uses in manipulation, and by studying impairments after selective nerve blocks we critically assess the use this information. Visuomotor mechanisms in feedforward control of fingertip actions are analyzed with novel techniques based on gaze behavior in manipulation. Finally, to explore the CNS processes that governs the specific control functions that we define at the systems level, in collaboration with other laboratories we examine task related activity in distributed neural networks by by brain imaging techniques.

Umeå University

Faculty of Medicine
Department of Integrative Medical Biology